Revised August 2016
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- Standards for Reporting Scientific Data
- Tools for Diagnostic Accuracy
- Ethical Considerations
- Types of Submissions
- Manuscript Preparation
- Online Submission and Tracking
- Clinical Chemistry Editorial Office
Clinical Chemistry, issued monthly, is published in print and electronically by the American Association for Clinical Chemistry. The journal welcomes contributions, either experimental or theoretical, in the field of laboratory medicine. It is the leading forum for peer-reviewed, original research on innovative practices in today’s clinical laboratory. In addition to being the most cited journal in the field, Clinical Chemistry has the highest Impact Factor among journals of clinical chemistry, clinical (or anatomic) pathology, analytical chemistry, and the subspecialties, such as transfusion medicine and clinical microbiology.
Submissions of the following nature are welcomed:
- Basic materials or principles
- Analytical techniques
- Molecular diagnostics
- Test utilization or testing-related health or financial outcomes
- Data processing
- Statistical analyses of data
- Clinical investigations in which laboratory testing has played a major role
- Laboratory animal studies of chemically oriented problems of human disease
Contributions should consist of subject matter that is original and significantly advances the state of knowledge of clinical chemistry, and conclusions that are justified from the design of the experiments and the data presented. The information must be sufficiently detailed to permit replication of the work by a competent worker in the field. Lastly, the writing must be clear, concise, and grammatically correct.
Equal consideration is given to original manuscripts in English from any country, regardless of membership in the Association. It is, however, advised that all non-English speaking authors enlist the aid of a native-English speaking colleague to correct English language usage before submission. Submissions must adhere to the “Uniform Requirements for Manuscripts Submitted to Biomedical Journals” (1).
All Clinical Chemistry submissions, correspondence, and reviews must be in English. Manuscript content and writing responsibility remains with the author; however, several professional writing/editing services are available to assist authors. Clinical Chemistry does not endorse any editing service nor is Clinical Chemistry responsible for any services performed. These include but are not limited to:
Contributions may be submitted via the manuscript tracking system at http://submit.clinchem.org. The “Information for Authors” will offer assistance with journal style and requirements. Please contact the Editorial Office via e-mail should you have any questions or need assistance: email@example.com.
- International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. Ann Intern Med 1997;126:36-47. [Full Text]
- Description of Analytical Methods and Results
- Studies with Human Subjects
- Animal Studies
- NIH Funding/Open Access Requirements
- Checklist for the Description of Sequence Variants at the Human Genome Variation Society
Manuscripts describing the development and evaluation of the performance of methods and instruments should discuss linearity, imprecision, analytical specificity, recovery, lower limit of detection, comparability with other analytical methods, lower limit of quantification and reference interval(s). Some clinical data are usually needed.
Document the analytical advantages of the new or modified method over existing methods.
Analytical method validations should conform to the protocols and requirements in the Center for Drug Evaluation and Research (CDER) Guidance for Industry: Bioanalytical Method Evaluation, 2001 (1).
Calibration curves and linearity: Data for these studies should be analyzed by linear regression analysis (if a linear response is obtained) and should include the slope, intercept, r2, standard deviation of residuals, and the standard deviations of the slope and intercept.
Standard deviations of repeated points may be included.
In preparing nonlinear calibration curves, authors may use any objective, statistically valid method but must specify the method used (see, e.g., (2)).
Imprecision: Studies must include estimates of "within-run" and "total" standard deviations (2). Each should be determined at low, normal, and above-normal concentrations with use of specimens that are in an appropriate biological matrix.
One method for estimating both within-run and total standard deviations is the analysis of variance experiment described in NCCLS EP5-T (3), which calls for two replicates per specimen per run and two runs per day for 20 days. This permits separate estimation of between-day and between-run, within-day standard deviations, as well as within-run and total standard deviations.
For acceptable alternatives that include only one run per day, see the cited document.
Indicators of Accuracy ("Trueness"): Accuracy (or “trueness” in the recent nomenclature) of a new method can be estimated by (a) analyses of certified Reference Materials by the new method or (b) comparisons of results of a new method with results of a Reference Method. These are the only accepted approaches to trueness. When neither is available, other evidence relevant to the ability of the method to measure the analyte (measurand) is needed. Recovery studies involve analyses after known amounts of analyte are added to the biological fluid on which the determination will be performed. Recovery of added analyte should be calculated [(final concentration – initial concentration)/added concentration], not the observed final concentration as a proportion of expected final concentration.
Interference studies should be performed to assess the effects of common interferents, including lipid particles, hemoglobin, bilirubin, and components of uremic plasma. Exogenous materials, such as ingredients of blood collection containers (tubes) and commonly used or commonly coadministered drugs that might interfere with the determination, should also be tested for interferences. Selection of materials to test should be guided by an understanding of the chemistry and physics of the measuring system. Thus chemicals that are structurally similar to the analyte should be tested to assess the selectivity of the method. (The term “selectivity” is preferred over specificity; selectivity can be quantified.) In characterizing non-spectrophotometric methods, chemicals that may interfere in the detection system should be studied more intensively than chemicals that are historically important for interference in spectrophotometric methods.
Comparison-of-methods studies should compare results by the new or proposed method with those by a reference-quality method or other generally accepted analytical method for which assay performance is documented (4, 5).
It is desirable to test 100 to 200 different samples from patients who have been selected to include a wide variety of pathologic conditions and to present a range of values for the analyte that includes those likely to be encountered in routine application.
For a table of the required number of samples, see Linnet (6).
If regression analysis is used for statistical evaluation of the data, supply slopes and intercepts (and their standard deviations) and standard deviations of residuals (Sy|x, often called standard errors of estimates). Unbiased (e.g., Deming) regression is typically required (7). A program to perform Deming regression is available online as a supplement from this journal (8).
The correlation coefficient has limited utility. Residuals plots [e.g., Bland-Altman (9, 10)] are often useful. On the horizontal axis, plot the mean of results by the two studied methods, not the result of one method.
Analytical sensitivity and detection limit: These terms are commonly confused. The International Union of Pure and Applied Chemistry defines analytical sensitivity as the ability of an analytical procedure to produce a change in signal for a defined change of the quantity. This is often visualized as the slope of the calibration curve.
The limit of detection (LOD) is defined as the lowest concentration or amount of an analyte that can be reliably identified as being qualitatively present in the sample. The limit of quantification (LOQ) is defined as the lowest concentration or amount of analyte that can be reproducibly quantified in a sample. The most acceptable criteria for ascertaining the LOQ is the concentration of analyte that can be measured with an imprecision of less than 20% and a deviation from target of greater or less than 20% (1). The operational definition of the LOD and LOQ must be supplied by the author. Additional considerations related to this topic are presented by Linnet (11).
Analytical quality: Results obtained for the performance characteristics should be compared objectively with well-documented quality specifications, e.g., published data on the state-of-the-art performance required by regulatory bodies such as CLIA 88, or recommendations documented by expert professional groups (12).
Reference interval (normal range): Depending on the conclusions of the accuracy studies, modification of an accepted reference interval may be indicated. Description of the reference interval study should include details about sampling; selection of subjects, including their number, age, and sex distribution; the statistical method for summarizing the results (13); and other factors that would influence the values obtained.
Chromatograms: Chromatograms from gas-liquid and liquid chromatography should usually be presented so that readers can see the efficiency of the separation and observe the resolution from interferents in the matrix. Similar images are often needed for electrophoretic separations.
Enzyme activities: Enzyme activities may be expressed in international units (U) or katals. Temperature and other key assay features must be described in the text or by reference to a published method.
When first mentioned in the text, enzymes (whether measured by activity or mass assays) must be numbered (EC no.) in accordance with the recommendations of the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology on the Nomenclature and Classification of Enzymes (16).
- Center for Drug Evaluation and Research (CDER) Guidance for Industry: Bioanalytical Method Evaluation, 2001.
- Linnet K, Boyd JC. Selection and analytical evaluation of methods – with statistical techniques. In: Burtis CA, Ashwood ER, Bruns DE. Tietz textbook of clinical chemistry and molecular diagnostics. 4th ed. St. Louis: Saunders, 2006: 353-407.
- NCCLS Tentative Guideline EP5-T. User evaluation of precision performance of clinical chemistry devices. Wayne, PA: National Committee for Clinical Laboratory Standards, June 1984.
- Carey RN, Garber CC. Evaluation of methods. In: Kaplan LA, Pesce AJ, eds. Clinical chemistry. Theory, practice and correlation, 2nd ed. St. Louis: CV Mosby, 1989:290–310.
- Koch DO, Peters T Jr. Selection and evaluation of methods. In: Burtis CA, Ashwood ER, eds. Tietz textbook of clinical chemistry, 2nd ed. Philadelphia: WB Saunders, 1994:508–25.
- Linnet K. Necessary sample size for method comparison studies based on regression analysis. Clin Chem 1999;45:882–94. [Abstract/Full Text]
- Linnet K. Evaluation of regression procedures for methods comparison studies. Clin Chem 1993;39:424–32. [Full Text]
- Martin RF. General Deming regression for estimating systematic bias and its confidence interval in method-comparison studies. Data supplement. GDR: Executable program for general Deming regression calculations and graphics. [Abstract/Full Text/Data Supplement]
- Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986;1:307–10. [Abstract]
- Altman DG, Bland JM. Commentary on quantifying agreement between two methods of measurement. Clin Chem 2002;48:801-2. [Extract/Full Text]
- Linnet K, Kondratovich M. Partly nonparametric approach for determining the limit of detection. Clin Chem 2004;50:732-40. [Extract/Full Text]
- Fraser CG, Petersen PH. Analytical performance characteristics should be judged against objective quality specifications. Clin Chem 1999;45:321–3. [Extract/Full Text]
- Solberg HE. Establishment and use of reference values. In: Burtis CA, Ashwood ER, eds. Tietz textbook of clinical chemistry, 4th ed. St. Louis: Saunders, 2006:425–48.
- Annesley TM. Ion Suppression in Mass Spectrometry. Clin Chem 2003;49:1041-44. [Full Text]
- Matuszewski BK, Constanzer ML, Chavez-Eng CM. Strategies for the assessment of matrix effect in quantitative bioanalytical methods based on HPLC-MS.MS. Anal Chem 2003;75:3019-30. [Abstract]
- International Union of Biochemistry and Molecular Biology, Nomenclature Committee. Enzyme nomenclature 1992. San Diego: Academic Press, 1992:862pp.
Describe statistical methods with enough detail to enable a knowledgeable reader with access to the original data to verify the reported results.
When possible, quantify findings and present them with appropriate indicators of measurement error or uncertainty.
Avoid sole reliance on statistical hypothesis testing, such as the use of P values, which fails to convey important quantitative information.
- Harris EK. On P values and confidence intervals (why can't we P with more confidence?) [Editorial]. Clin Chem 1993;39:927-8. [Full Text]
- Henderson AR. Chemistry with confidence: should Clinical Chemistry require confidence intervals for analytical and other data? [Opinion]. Clin Chem 1993;39:929-35. [Abstract/Full Text]
Authors are responsible for ensuring compliance of human studies with the Helsinki Declaration of 1975 as revised in 2008: http://www.wma.net/en/30publications/10policies/b3/index.html. Approval by the appropriate institutional committee on human research (Institutional Review Board) must be documented in the manuscript and, unless excepted by that committee, informed consent of all participants studied for the report must be included.
Authors are responsible for ensuring that studies of animals are in accordance with the Committee on Care and Use of Laboratory Animals. The information can be found in the Guide for the care and use of laboratory animals. Washington, DC: Institute of Laboratory Animal Resources, National Research Council, 1985:83pp.
The National Institutes of Health (NIH) has implemented its "Policy on Enhancing Public Access to Archived Publications Resulting from NIH Funded Research." This policy requests that authors reporting research that is funded (in whole or part) by a current NIH grant submit to NIH PubMed Central (PMC) manuscripts after they have been peer reviewed and accepted for publication in scientific journals. The “accepted manuscript” is the version of the manuscript after the author’s final revision but before post-acceptance editing and copyediting. The Policy is available online at http://grants.nih.gov/grants/guide/notice-files/NOT-OD-05-045.html. The policy applies to manuscripts accepted for publication in Clinical Chemistry on or after May 2, 2005.
The policy requests that the release date to the public be within 12 months after the official date of final publication. Clinical Chemistry’s existing policy that has been in effect since the Journal first appeared online in 1998 is to make all content publicly available 12 months after publication date. Authors have the option to request that their papers be made freely available immediately at the time of online publication, for a fee of $3500. For more information or to request open access publication, contact the Editorial Office at firstname.lastname@example.org.
If an author chooses to submit an accepted manuscript to PMC, he or she will be asked to indicate when that manuscript should be made available to the public. Consistent with our existing policy, the American Association for Clinical Chemistry (AACC) grants the author permission to allow public release of the accepted manuscript through PMC 12 months after publication in Clinical Chemistry.
Accepted manuscripts and published articles in Clinical Chemistry are protected by AACC’s copyright at the time of publication and thereafter. All copyright restrictions apply.
The author’s manuscript available on the PMC site is not the Clinical Chemistry article. This version of the manuscript may contain factual errors that were detected during the post-acceptance editing phase. Data, text, conclusions, tables, and figures may all differ from the published version available at www.clinchem.org. The final published version is the Clinical Chemistry article. Clinical Chemistry assumes no responsibility for earlier versions.
The AACC requires that authors add the following disclaimer to the manuscript before sending it to PMC:
"This is an un-copyedited authored manuscript copyrighted by the American Association for Clinical Chemistry (AACC). This may not be duplicated or reproduced, other than for personal use or within the rule of 'Fair Use of Copyrighted Materials' (section 107, Title 17, U.S. Code) without permission of the copyright owner, AACC. The AACC disclaims any responsibility or liability for errors or omissions in this version of the manuscript or in any version derived from it by the National Institutes of Health or other parties. The final publisher-authenticated version of the article will be made available at http://www.clinchem.org 12 months after its publication in Clinical Chemistry.”
Authors may contact Clinical Chemistry via e-mail at email@example.com with any questions related to submitting their accepted manuscripts to PMC. More information from NIH can be found at http://publicaccess.nih.gov/FAQ.htm.
Requirements for the description of sequence variants can be found at http://www.hgvs.org/mutnomen/checklist.html.
- Studies of Diagnostic Accuracy (STARD)
- Outcomes Studies (CONSORT)
- Minimum Information about a Microarray Experiment (MIAME)
- Minimum Information about Quantitative Real-Time PCR Experiments (MIQE)
Explanatory document, with examples: http://www.clinchem.org/cgi/content/full/49/1/7
STARD guidelines: http://www.clinchem.org/cgi/content/full/49/1/1
For studies of diagnostic accuracy of tests, complete the STARD Checklist for Evaluations of Diagnostic Accuracy (1) electronically upon submission. Do not send the checklist via e-mail or upload it as supplemental material.
-Provide literature reference(s) describing the evaluated test(s) and criterion "gold standard" test(s) or include detailed descriptions of them.
-Follow accepted methodologic standards including the following:
- Specify spectrum of evaluated patients (age and sex distributions, eligibility criteria, and summary of symptoms or disease stage).
- Analyze pertinent subgroups of subjects (e.g., symptomatic and asymptomatic patients).
- Avoid verification bias (usually by application of a "gold-standard" test to all subjects rather than to a clinically selected subset).
- Categorize test results and patients independently to avoid reviewer bias (usually by performance of tests with blinding to patient information and vice versa).
- Provide confidence intervals (or SE) for indices of diagnostic accuracy such as sensitivity/specificity, likelihood ratios, and areas under receiver-operating characteristic (ROC) curves (3).
- Indicate the number of indeterminate test results and their use (if any) in further data analysis.
- Provide laboratory data on analytical imprecision of the test (usually day-to-day CV at two or more concentrations) or reproducibility of observer interpretation (e.g., for a visually read, dichotomous [positive/negative] test).
-When evaluating diagnostic accuracy in clinical studies, simple testing of the significance of differences between mean values of patient groups (e.g., by Student’s t-test) provides insufficient information to assess diagnostic accuracy.
-Scatter plots of data, calculations of diagnostic sensitivities and specificities and their confidence intervals (3), and use of approaches such as ROC curves (4), cumulative distribution analyses (5), likelihood ratios (6), and discriminant analysis (7) provide information that is appropriate to specific situations.
-Confidence intervals should be provided (1).
-Discussions of predictive values in illustrative settings may be useful additions to assess the potential clinical utility of tests.
-Analysis of serial measurements requires special attention (8).
- STARD Group. Towards complete and accurate reporting of studies of diagnostic accuracy: the STARD statement. Clin Chem 2003;49:1-6. [Abstract/Full Text]
- Bossuyt PM, Reitsma JB, Bruns DE, Gatsonis CA, Glasziou PP, Irwig LM, et al. The STARD statement for reporting studies of diagnostic accuracy: explanation and elaboration. Clin Chem 2003;49:7-18. [Abstract/Full Text]
- Harper R, Reeves B. Reporting of precision of estimates for diagnostic accuracy: a review. BMJ 1999;318:1322-3. [Full Text]
- Zweig MH, Campbell G. Receiver-operating characteristic (ROC) plots: a fundamental evaluation tool in clinical medicine [Review]. Note that in Figs. 4-12 in this paper, the labels for the x-axis at the top and bottom are reversed. The (correct) dual labeling of the x-axis solves the problem of whether to plot specificity or 1 - specificity on the x-axis. Clin Chem 1993;39:561-77. [Abstract/Full Text]
- Krouwer JS. Cumulative distribution analysis graphs-an alternative to ROC curves [Technical Brief]. Clin Chem 1987;33:2305-6.
- Albert A. On the use and computation of likelihood ratios in Clinical Chemistry. Clin Chem 1982;28:1113-9. [Abstract/Full Text]
- Solberg HE. Discriminant analysis. Crit Rev Clin Lab Sci 1978;9:209-42.
- Matthews JNS, Altman DG, Campbell MJ, Royston P. Analysis of serial measurements in medical research. Br Med J 1990;300:230-5.
The CONSORT statement (1), although designed for randomized controlled trials and used for therapeutic rather than diagnostic interventions, is recommended as an often-useful guide.
For questions, contact Clinical Chemistry via e-mail at firstname.lastname@example.org.
- Moher D, Schulz KF, Altman DG for the CONSORT Group. The CONSORT statement: revised recommendations for improving the quality of reports of parallel group randomized trials. www.consort-statement.org.
The MIAME Checklist can be found at http://fged.org/projects/miame/.
MIAME describes the minimum information about a microarray experiment that is needed to enable interpretation of the results of the experiment unambiguously and potentially to reproduce the experiment.
The MIAME checklist is a description of MIAME principles designed to help authors, reviewers, and editors of scientific journals meet MIAME requirements and to make microarray data available to the community in a useful way.
MIAME is neither a dogma nor a legal document - it assumes a cooperative data provider and a fair reviewer.
For studies that include quantitative real-time PCR experiments, complete the MIQE checklist for evaluation of qPCR experiments during electronic submission. Do not send the checklist via e-mail or upload it as supplemental material. The full text of the MIQE guidelines is available online: http://www.clinchem.org/cgi/content/short/55/4/611. A PDF version for all essential components of the checklist can be obtained by the link above.
Recommended nomenclature should be used, including:
- qPCR for quantitative real-time PCR
- RT-qPCR for reverse transcription quantitative real-time PCR
- reference genes instead of housekeeping genes
- hydrolysis probes instead of TaqMan® probes
- dual hybridization probes for HybProbes® (LightCycler®) probes
- quantification instead of quantitation
- Cq instead of Ct, Cp, or TOP
- quantification cycle instead of threshold cycle or crossing point
Authors are also encouraged, but not required, to include the additional desirable items of the MIQE guidelines (1). The MIQE guidelines are intended to help authors plan, perform and present qPCR experiments. They are also a guide for reviewers and editors to judge the quality of qPCR data. Incomplete information may be grounds for manuscript rejection. Use of Supplemental Data is encouraged as necessary. The most common errors in performing and reporting qPCR data include:
- Not enough information for others to replicate the experiment, including how the nucleic acid was prepared, reverse transcribed, and amplified. Primer sequences are required. Probe sequences are strongly encouraged especially in methods manuscripts, but their omission may be acceptable in clinical manuscripts if they are commercially available as products.
- Inadequate storage and/or nucleic acid preparation, leading to poor nucleic acid quality and variable results.
- Suboptimal primers for reverse transcription and/or PCR resulting in low yield, specificity and/or PCR efficiency.
- Inappropriate analysis of data.
- Use of a single reference gene in RT-qPCR without justification (2).
The guidelines require not only delineation of what was done, but presentation of evidence that validates the method used. For example, these include evidence of RNA integrity and purity, PCR specificity, calibration curves and calculations of PCR efficiency and limits of detection. At the option of the editor, MIQE requirements may be relaxed in reports using qPCR arrays, although all manuscripts will be judged on their relative merit, and the relative merit of a manuscript using qPCR increases as compliance with the MIQE guidelines increases.
- Bustin SA, Benes V, Garson JA, Hellemans J, Huggett J, Kubista M, Mueller R, Nolan T, Pfaffl MW, Shipley GL, Vandesompele J, Wittwer CT. The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem. 2009 Apr;55(4):611-22.
- Vandesompele J, De Preter K, Pattyn F, Poppe B, Van Roy N, De Paepe A, Speleman F. Accurate normalization of real-time quantitative RT-PCR data by geometric averaging of multiple internal control genes. Genome Biol. 2002 Jun 18;3(7):RESEARCH0034.
In order to ensure the highest ethical standards, Clinical Chemistry adheres to the recommendations from the International Committee of Medical Journal Editors (ICMJE) and the Committee on Publication Ethics (COPE) for guidance on policies and procedures regarding scientific misconduct. Misconduct including, but not limited to, the following is strictly prohibited and will result in immediate removal of a paper from consideration by the journal.
Submissions that are under review or that have been previously published with another journal.
Duplicate Publications and Plagiarism
Manuscripts that have substantial overlap with a manuscript that has already been published, without proper citation.
Research or scientific articles are submitted directly from authors. There are no restrictions on topics that are considered for publication, as long as the subject matter is original and relates experimentally or theoretically to the field of laboratory medicine. The information must be sufficiently detailed not only to enable readers to understand and appreciate the material presented, but also to permit replication of the work by other scientists in the field.
Articles should contain a structured abstract limited to 250 words and formatted to include separate headings of: Background, Methods, Results, and Conclusions. The main text should not exceed 3,500 words. The manuscript should have no more than 40 references and a total of 6 tables and/or figures. Supplemental data are permitted for Articles.
Articles should list no more than 20 authors, with any additional contributors listed in the Acknowledgments. Although exceptions are rare, you may email email@example.com detailing each author's contribution to your submission, which will be forwarded to the editor.
Authors may submit short videos to complement their Articles. Videos can be used to illustrate a laboratory technique, hardware prototype, or clinical presentation that would benefit from such an addition, or to visually communicate to the reader novel features, special steps in a procedure, pitfalls, or other information that may not be easily conveyed through text or a figure. Videos should be of high quality, no more than 5 minutes in length, and submitted as .mp4 files. Please do not send proprietary file types such as .wmv (Windows Media) and .rm (Real Media) files.
Authors of Articles will be prompted at submission to provide a brief summary of their work, not to exceed 100 words. In the event of acceptance, this will be recorded and included as an audio file in all online versions of the table of contents. The Audio Summary should address the following questions:
- What was the paper about/what was the rationale for the study?
- How did you approach the problem?
- What were your findings?
- What are the implications of the findings and how do they add to the field?
A simple phonetic spelling of the first author’s full name should also be provided.
Citation Classics are typically invited submissions that highlight a landmark article in the field of clinical chemistry. In this feature, one of the authors of the original article provides some historical insights and anecdotal stories surrounding its publication.
Citation Classics should not include an abstract and are limited to 600 words, no more than 6 references, and no more than 5 authors. Generally, tables and figures are not permitted; however, if the text does not exceed 500 words, one table or figure will be allowed. Also, supplemental data are not permitted for Citation Classics.
This monthly feature provides a forum for informing readers about general items of interest. Topics might include announcements for upcoming conferences, awards received by members of the AACC, announcements of new features in the journal, humorous items, artwork or photographs from readers, or general scientific news. Readers may submit items for consideration in the following categories: Unveiling the Right Side, What Is Your Guess?, and Genetic Metabolic Series, following the specific guidelines for each. The editors will make the final decision on the appropriateness and priority for inclusion in this section of the journal.
Please note that the journal is not currently considering unsolicited submissions to the Technology Corner, Science in the Arts, and Best of Clinical Chemistry sections.
Clinical Case Studies are submitted directly from authors. These articles are intended to be educational, with the goal of helping to develop or improve problem-solving skills. Clinical Case Studies may report unusual (although not necessarily rare) biochemical manifestations of disease, atypical presentation of disease, situations where the laboratory helped in making or clarifying a diagnosis, or information that would be helpful in understanding the pathophysiology of a disease.
Two accompanying commentaries will introduce additional concepts that may be useful to readers, discuss confounding factors that might affect a diagnosis or analytical result, and/or provide comments about the case itself. Commentaries are invited and authored by clinical chemists, physicians, or scientists with expertise in the area.
A Clinical Case Study should not include an abstract. It should, however, include a case description followed by the case discussion, limited to 1,500 words total. References are limited to 10, and the tables and figures are limited to 2 in total. Authors should include 3-5 brief questions regarding the case that would stimulate discussion and learning about the disease state. These questions will be circulated to educational centers before publication. The author should also list up to 5 points to remember at the end of the manuscript. The questions and points are not included in the manuscript count of 1,500 words. The case should read as a bit of a mystery or diagnostic dilemma. The case title, case description, and questions should not disclose the diagnosis. Supplemental data are not permitted for Clinical Case Studies. No more than 5 authors should be listed.
Commentaries are limited to 300 words. They should not include an abstract, references, or tables and figures and should have no more than 5 authors. Supplemental data are not permitted for Commentaries.
Corrections are unique and will be considered on a case-by-case basis. Authors are encouraged to contact the Editorial Office at firstname.lastname@example.org should they wish to submit a Correction or should they find a printer error that needs correcting.
These are typically invited submissions. Editorials provide opinions and observations by an expert in the field about the subject matter or content of a scientific paper published in Clinical Chemistry. In addition to further educating readers on a selected topic, Editorials are designed to stimulate readers to formulate their own opinions about a paper and its value to the field. In some cases, Editorials may also be independent opinions and observations about a controversial topic or changes taking place in the field.
Editorials are limited to 1,500 words. They should not include an abstract. References are limited to 15, and tables and figures are not permitted. No more than 5 authors should be listed. Supplemental data are not permitted for Editorials.
The Genetic Metabolic Series falls under the Clinical Chemist and contains short clinical cases in biochemical genetics. Each article will include the actual case presentation, a chromatogram, the biochemical pathway of the defect, and a short case discussion. Submissions should not exceed 600 words in length and should include no more than 2 tables or figures and 1 reference.
These biographical articles are commissioned to present the achievements of distinguished clinical chemists, as well as their philosophical views on their professional life and the field of clinical chemistry.
Letters are submitted directly from authors and can be used to report an observation or to discuss a previously published original Article. Letters in response to papers other than Articles will not be considered for publication. Letters report observations on interferences, suggestions to improve test performance, or other observations that are of importance to the wider audience. A Reply to a Letter may also be solicited by the editors. The one figure or table provided should be concise and should not be multipart (i.e., Fig. 1A, 1B, 1C, Part 1, Part 2).
A Letter to the Editor is limited to 750 words. It should not include an abstract. The references are limited to 5, and only 1 table or figure is permitted. Supplemental data are not permitted for Letters to the Editor.
A Reply is limited to 750 words. It should not include an abstract. The references are limited to 5, and only 1 table or figure is permitted. Supplemental data are not permitted for Replies.
Letters to the Editor and Replies should list no more than 8 authors, with any additional contributors listed in the Acknowledgments. Although exceptions are rare, you may email email@example.com detailing each author's contribution to your submission, which will be forwarded to the editor.
In some instances, editors may request that a submission of another article type to Clinical Chemistry be decreased to meet the requirements of a Letter to the Editor.
Mini-Review articles are typically invited submissions. Mini-Reviews are intended to provide a general overview of a topic. Basic information is provided, along with selected references that can aid the reader in obtaining additional information about the subject. The use of illustrative figures or tables is encouraged.
A Mini-Review article should consist of a structured abstract limited to 250 words with headings of Background, Content, and Summary. The text should not exceed 3,500 words. The manuscript should have no more than 40 references and a total of 4 tables and/or figures. Supplemental data are permitted for Mini-Review articles.
Mini-Reviews should list no more than 5 authors, with any additional contributors listed in the Acknowledgments. Although exceptions are rare, you may email firstname.lastname@example.org detailing each author's contribution to your submission, which will be forwarded to the editor.
Obituary announcements and associated biographies can be commissioned by the Journal or submitted by authors. Prior to submission of an Obituary, authors should contact the Journal with information about the person who has passed away and with a description of the individual’s career achievements and unique contributions. A decision will then be made on proceeding with the Obituary.
Obituaries should include personal information about the deceased (birthplace, education, place of residence, employment), highlights of this person’s achievements (research accomplishments, awards, elected positions, committees, service to the profession), and anecdotal information about what made the person unique.
Obituaries are limited to 600 words with no abstract, references, or tables. One figure/image file is permitted. Supplemental data are not permitted for Obituaries.
Opinion articles are invited submissions that present the belief or personal view of the author(s) on a specific topic. An opinion implies a conclusion thought out yet open to dispute. Opinion articles are often a formal expression by an expert of his/her judgment or advice. Unlike Editorials and Letters to the Editor, Opinion articles do not comment on, or refer to, specific papers published in the journal.
An Opinion should not include an abstract and is limited to 1,500 words, 15 references, 1 table or figure, and no more than 5 authors. Supplemental data are not permitted for Opinions.
These articles are invited submissions. Perspectives highlight a clinical, analytical, or basic science report that was published in a journal other than Clinical Chemistry but has implications for the practice of clinical chemistry.
Perspectives should not include an abstract. They are limited to 1,500 words, 5 references, 1 table or figure, and no more than 5 authors. Supplemental data are not permitted for Perspectives.
These articles are typically invited submissions from experts in a selected discipline and provide different viewpoints on a topic that may be controversial, lacks consensus in the scientific community, or may be of high public interest. In most cases an author or group of authors is asked to write the first half of the article, describing the importance of the topic, challenges to be addressed, current limitations, and/or unmet needs. A second author or group of authors is invited to provide a “Counterpoint” discussion of a different viewpoint or critical factors.
Point/Counterpoint submissions should not include an abstract. The manuscript is limited to 1,500 words, 15 references, and 1 table or figure. Supplemental data are not permitted for Point/Counterpoint.
This invited feature is meant to highlight a timely and important issue, either clinical or analytical, through a series of questions posed to leaders in the field by a moderator. The moderator is required to include an introductory paragraph and photographs of each expert. Five to 8 questions may be posed to 3 to 5 experts with the moderator documenting the answers. Submissions are limited to 3,500 words.
These articles are invited submissions. Reflections are authored by highly accomplished scientists in their field who have greatly contributed to science. Reflections will be reserved for special issues and will focus on the specific advancements the individual has made in his or her field.
Reflections are limited to 2,000 words and should not include an abstract. The references are limited to 20, and 1 table or figure is permitted. Supplemental data are not permitted for Reflections.
Review articles are typically invited submissions. Reviews are intended to provide comprehensive coverage of a topic, including background clinical or analytical information, the relevance and importance of the subject matter, and potential future directions. The use of illustrative figures or tables is encouraged.
A Review article should consist of a structured abstract with headings of Background, Content, and Summary limited to 250 words. The text should not exceed 5,000 words. The manuscript should have no more than 75 references and a total of 6 tables and/or figures. Supplemental data are permitted for Review articles.
Reviews should list no more than 15 authors, with any additional contributors listed in the Acknowledgments. Although exceptions are rare, you may email email@example.com detailing each author's contribution to your submission, which will be forwarded to the editor.
Special Reports may be submitted directly by authors or invited by the journal. The types of papers that would be considered include consensus reports, guideline development, position statements, or evidence-based recommendations on test utilization or quality specifications. The editors may also decide to classify other miscellaneous submissions under this heading.
A Special Report should consist of a structured or unstructured abstract limited to 250 words. The main text should be no more than 5,000 words. The manuscript should have no more than 40 references and a total of 4 tables and/or figures. Supplemental data are permitted for Special Reports.
Special Reports should list no more than 20 authors, with any additional contributors listed in the Acknowledgments. Although exceptions are rare, you may email firstname.lastname@example.org detailing each author's contribution to your submission, which will be forwarded to the editor.
Submissions should highlight the creative side of someone in the field of chemistry. This can be poetry, a short story, photographs, or other creative artwork. Submissions are limited to 400 words and/or one image, photograph, or poem. All submissions are subject to review. Cover letter should state interest in contributing to Unveiling the Right Side and must be submitted under the category of Clinical Chemist.
Submissions for this 1-page quiz should consist of an image or lab values, a case description (less than 75 words), 3 questions, case discussion (less than 75 words), and no more than 5 references. Cover letter should state interest in contributing to What Is Your Guess? and must be submitted under the category of Clinical Chemist.
What Is Your Guess? submissions should list no more than 5 authors. Although exceptions are rare, you may email email@example.com detailing each author's contribution to your submission, which will be forwarded to the editor.
- Author Contribution Requirements
- Manuscript Guidelines
- Submission/Publication Fees
- Journal Categories
- Title Page
- Disclosures/Conflict of Interest
- Figure Captions
- Supplemental Data
Clinical Chemistry follows the recommendations for authorship set out by The International Committee of Medical Journal Editors (ICMJE). In accordance with these recommendations, manuscripts are considered for publication with the understanding that each listed author must meet the following criteria:
- Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; AND
- Drafting the work or revising it critically for important intellectual content; AND
- Final approval of the version to be published; AND
- Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Any change in authors and/or contributors after initial submission must be approved by all authors. This applies to additions, deletions, change of order to the authors, or contributions being attributed differently. If a change is made to the author list after submission or during any revision, the submitting author must send an e-mail to firstname.lastname@example.org explaining the reason for the change and copying all authors for their approval. Any additions or deletions must be made in the electronic submission record as well as on the manuscript itself. At revision, be sure to select "Yes, the authorship has changed" when prompted.
Author limits may be imposed for certain submission types. Please review the specific requirements for your submission type. Please list only the allowed number of authors in the author list, with the remaining contributors listed in an Acknowledgment. Exceptions may be made at the discretion of the editor.
Any alterations made to the manuscript after submission must be approved by the editor. Authors may upload the request letter to the online submission system as a supplemental file or send the letter via e-mail to the Clinical Chemistry editorial office at email@example.com. The editor may contact any of the authors and/or contributors to ascertain whether they have agreed to any alteration.
- The International Committee of Medical Journal Editors (ICMJE) Uniform Guidelines for Manuscripts Submitted to Biomedical Journals (1) specifically state that “all contributors who do not meet the criteria for authorship, such as a person who . . . provided purely writing assistance" be named in the acknowledgments.
- Important contributions to an article should be recognized and appropriately attributed in that article.
Good medical writers and editors can make valuable contributions to the publication process, often improving the clarity of the communication, broadening the scope of literature review, providing an extra level of data review, adding balance and objectivity, and shortening the time needed for manuscript development.
The American Medical Writers Association (AMWA) http://www.amwa.org believes that these important contributions deserve recognition.
- Readers benefit from knowing about the involvement of professional writers and editors.
Disclosing the editorial contribution and the source of funding of the writer and editor allows the reader to make informed judgments about the objectivity of the article.
Note that the AMWA position statement recommends acknowledgment of pertinent professional or financial relationships as well as acknowledgment of the contributions of writers and editors.
It also recommends that the person being acknowledged be given the opportunity to grant or refuse permission for the acknowledgment.
- International Committee of Medical Journal Editors. Uniform requirements for manuscripts submitted to biomedical journals. Ann Intern Med 1997;126:36-47. [Full Text]
- MS Word document (.doc or .docx) is required for all submissions.
- All figures must be uploaded separately as Image Files in Tagged Image File Format (.tiff), Encapsulated Postscript (.eps) or PowerPoint (.ppt) with embedded fonts.
- All submissions must be double-spaced, 1 inch margin, twelve-point font size in Arial, Helvetica, Times New Roman and Symbol font (for non-text characters).
- All submissions must be page numbered.
- All submissions must have line numbers included in the text.
- Do not use headers or footers.
- Use standard abbreviations and define all nonstandard abbreviations.
- All submissions require a title page.
- Reporting of Concentration Units:
- Analyte concentrations will be expressed in the text in the traditional mass unit (mg/dL, ng/ml, and so forth) followed by the SI unit in parentheses. Exceptions would include those analytes in which SI units are used globally, such as electrolytes (use mmol/L for sodium, potassium, chloride, and CO2 values), or cases in which the traditional unit and the SI unit differ by only a factor of 1000 in both the numerator and denominator (e.g., ng/mL vs µg/L). In such cases, the unit of measure consistent with common practice will be used.
- The unit of measure mg/L should be used only when referring to SI units or when national or international guidelines require or recommend that the concentration of an analyte be expressed in that unit of measure, such as for high-sensitivity C-reactive protein. The unit of measure U/L will be used for most enzyme activites.
- Only traditional units will be used for tables and figures in the printed version of a report; SI conversion factors will be provided in legends. All tables and figures will also be presented in SI units. These tables and figures will be made available in online supplements to published articles and letters. Authors will provide both versions before final acceptance of a manuscript. SI units are available at Bureau International des Poids et Mesures.
- Supplemental Data are accepted for online publication only and are limited by submission types (See Types of Submissions for details).
- Follow the guidelines for length restrictions, abstract, reference, table and figure, and supplemental data limits as outlined in the chart below:
|Type of Submission||Word Limit*||Structured** (S) or Unstructured (U) Abstract:Word Limit||Maximum Number of References||Total Number of Tables/Figures||Supplemental Data Permitted|
|Clinical Case Studies
w/ 3-5 questions and up to 5 points to remember
|Letter to the Editor / Reply||750||Nonapplicable||5||1***||No|
|Special Report||5,000||S or U: 250||40||4||Yes|
*Word limit consists of the body of the manuscript only; it does not encompass the title page, abstract, acknowledgments, references, tables, figure legends, figures, or Clinical Case descriptions, questions, and points to remember.
**Structured abstracts contain the headings (1) BACKGROUND, (2) METHODS, (3) RESULTS, (4) CONCLUSIONS for all applicable article types except for Reviews and Mini-Reviews. Abstracts for Reviews and Mini-Reviews contain the headings (1) BACKGROUND, (2) CONTENT, (3) SUMMARY.
***If a figure accompanies the paper, the image should not be multipart (i.e., Fig. 1A, 1B, 1C, Part 1, Part 2).
Authors are not required to pay submission fees in order to submit their work to Clinical Chemistry. If color figures are present in the submission, authors of accepted papers may be required to pay a fee for color printing at the time of publication.
Authors have the option to request that their papers be made open access immediately at the time of online publication, for a fee of $3500. For more information or to request open access publication, contact the Editorial Office at firstname.lastname@example.org. All papers are made open access one year after publication.
Articles are grouped in the journal according to subject. Upon submission, authors are required to select the journal category that best describes their manuscript from the list indicated below:
- Molecular Diagnostics and Genetics (MDG)
- Evidence-Based Laboratory Medicine and Test Utilization (TUO)
- Hemostasis and Thrombosis (HAT)
- Proteomics and Protein Markers (PPM)
- Cancer Diagnostics
- Lipids, Lipoproteins, and Cardiovascular Risk Factors (LLP)
- Drug Monitoring and Toxicology (DMT)
- Hematology (HEM)
- Endocrinology and Metabolism (END)
- Point-of-Care Testing
- Automation and Analytical Techniques (AAT)
- Informatics and Statistics
- Laboratory Management (LMA)
- General Clinical Chemistry (GCC)
- Animal Clinical Chemistry (ANI)
- Clinical Immunology (CLI)
- Pediatric Clinical Chemistry (PED)
- Nutrition (NUT)
- Infectious Disease
- Other Areas of Clinical Chemistry (OTH)
The first page of the manuscript should include the following information:
- full title of submission, which should include only generic, not trade, names when describing a test, assay, etc.;
- running head of fewer than 50 characters (including spaces);
- list of all authors (first name, middle initial, and last name, in that order);
- names of each author’s institution and an indication of each author’s affiliation;
- name, address, telephone and fax number, and e-mail address of the corresponding author;
- any previous presentation of the manuscript;
- list of abbreviations, in order cited; and
- list of any “Human Genes" discussed in the paper. For each gene, indicate the gene symbol and gene name approved by the HUGO Gene Nomenclature Committee. Include other name(s) that are used in the paper or are widely used in the literature for the gene.
Structured abstracts should be formatted to include separate headings of: Background, Methods, Results, and Conclusions. For Mini-Review and Review articles the headings should be: Background, Content, and Summary. Both structured and unstructured abstracts are subject to a limit of 250 words.
Unstructured abstracts do not require separate headings.
Citation Classics, Clinical Case Study, Commentary, Editorial, Inspiring Minds, Letters to the Editor, Reply, Obituary, Opinion, Perspective, and Point/Counterpoint submissions do not require an abstract.
In addition to appearing at the beginning of the manuscript, abstracts must be uploaded to the abstract field of the Manuscript Metadata page online upon submission.
The body of the manuscript should be written as concisely as possible and must not exceed the manuscript category word limits described herein. All pages must be double-spaced and all lines numbered. The body of the paper should include: Introduction, Materials and Methods, Results and Discussion.
- Introduction - why was the study undertaken?
- Materials and Methods - how was the study done?
- Results - what did the study find?
- Discussion - what might it mean, why does it matter, what next?
Full corporate names of manufacturers of materials should be utilized (omit Inc., Co., GmbH and similar words). After the first mention, use a shorter name (e.g., for Bio-Rad Laboratories, use Bio-Rad). Only the manufacturer’s name should be used, unless the item in question was a gift, in which case the city, state, and e-mail or website of the company should be included.
Reporting of Concentration Units: Analyte concentrations will be expressed in the text in the traditional mass unit (mg/dL, ng/ml, and so forth) followed by the SI unit in parentheses.
Use of human subjects requires a statement in the text indicating whether the procedures followed were approved by your institution's responsible committee or were in accordance with the current revision of the Helsinki Declaration and whether subjects gave informed consent.
Accession numbers for data sets or sequence reads that have been deposited in a public database should be provided in the Materials and Methods section of the text.
Where applicable, a ClinicalTrials.gov identifier for a registered clinical study should be listed both at the end of the abstract and at the first mention of the trial acronym in the main text.
All authors are required to complete a full disclosure form upon submission. Please note that the form is not limited to those disclosures that constitute a potential conflict of interest. The disclosure form is electronic and completed during the submission process within the Bench>Press submission system. Disclosures should not be included in an Acknowledgment or elsewhere within the submitted manuscript file. All grants or other forms of research funding applicable to the report, as well as all relevant employment or leadership roles, consulting or advisory relationships, stock ownership, and patents occurring within the previous 24 months should be included in this form. The recipient(s) of all applicable grants or other funding must be specified. Failure to adhere to this guideline may result in a return of the submission to the author for correction.
In order to complete disclosures, register with Clinical Chemistry at http://submit.clinchem.org/cgi/registration using a valid e-mail address. Each author is required to be registered and must individually complete the disclosures. If you are registered under a different e-mail address from the one the submitting author has provided, you will not be able to access the disclosures. After registration, the system may take up to 15 minutes to refresh before the disclosure form appears.
Each author is expected to disclose any relevant financial relationships held personally within the last 24 months. Any companies or proprietary entities producing scientific services, which have an investment, licensing, or other commercial interest in the subject matter under consideration in the submitted manuscript, must be disclosed.
Such information is held in confidence while the manuscript is under review and does not influence the editorial decision on reports of research; upon acceptance, relevant information is added to the manuscript for publication.
Authors of editorials are expected to be free of significant financial associations with companies that may be affected by topics discussed in the manuscript and must also complete a full disclosure at the time of submission.
The American Medical Writers Association (AMWA) recognizes the valuable contributions of biomedical communicators to the publication team. Biomedical communicators who contribute substantially to the writing or editing of a manuscript should be acknowledged with their permission and with disclosure of any pertinent professional or financial relationships. In all aspects of the publication process, biomedical communicators should adhere to the AMWA code of ethics at http://www.amwa.org/amwa_ethics.
Acknowledgments are limited to 60 words and should follow the main text of the manuscript directly above the reference section in a separate paragraph heading labeled “Acknowledgments.” They should not appear as footnotes.
Do not include financial support, or other disclosure/conflict of interest information in the Acknowledgment. This information should be included in the Author Disclosure/Conflict of Interest form. If you include research funding in the Acknowledgment, you must specify which author or authors received the funding or if the funding was given to the group or institution. Editorial staff will transfer this information to the disclosure section prior to publication if the paper is accepted.
References should appear in a separate section directly following the body of the manuscript. The section must be labeled “References” with no additional punctuation. In-text citations should correspond to the numbered references in this list and should be formatted as follows: (1) or (1, 2).
- Italic or boldface type is prohibited in the referenced citations.
- List and number the references in the order that they appear in the text.
- Do not use the MS Word document numbering tool. Number each reference manually with the numeral and a period, followed by a space.
- For articles with more than seven authors, list the first six authors followed by "et al." For seven or fewer, list all authors.
- Authors’ names are inverted (last name, first/second initial). Do not add periods or commas within an individual author name; however, separate author names with a comma and end the author list with a period (Smith J, Doe JJ, Adams B.).
- Capitalize only the first word of the title or subtitle, and any proper names that are part of the title. The title should end with a period.
- The Journal names should be abbreviated as indicated at PubMed. For a list of journal abbreviations, please visit: LinkOut Journals.
- Do not add a period after the journal abbreviation, but continue with a space followed by the year.
- The year should be followed by a semicolon and then the volume number, which is followed by a colon and then the page numbers. Delete redundant numbers, for example 1998;12:231-45.
- Do not include the months in parentheses; this information is not needed.
- Use inclusive page numbers for articles and book chapters.
Abstract and supplement numbers should be provided, if applicable. Citations of unpublished abstract books, manuscripts in preparation or under review, personal communications, and manufacturers’ information should only be cited in the text and should not appear in the reference list. Personal communications should also be listed parenthetically and should contain the first initial and last name of the contact as well as the month and year of the communication. A copy of written permission from the contact to use the communication must also be provided. Published manuscripts and manuscripts that have been accepted and are pending publication should be cited in the reference list. Note that unpublished material must be published, at least online, by the time of publication of the citing article.
In-press references cited in the reference list must be accompanied by a copy of the cited manuscript and a letter of acceptance, or a complete author proof from the publisher. These resources should be uploaded as supplemental data along with the manuscript and other print materials.
The submission system will extract the references from the submitted MS Word document (.doc or .docx) to display in a hyperlinked HTML format as an aid for reviewers and editors. This linking option allows for the checking of the correct formatting and the accuracy of the citations.
Authors must check the linking of their references to PubMed during the “Ready for You to Proof” stage of submission. Correct linking of the references depends on strict adherence to Journal style as indicated.
- Journal article with seven or fewer authors:
1. Vermeersch P, Mariën G, Bossuyt X. A case of pseudoparaproteinemia on capillary zone electrophoresis caused by geloplasma. Clin Chem 2006;52:2309-11.
- Journal article with more than seven authors:
2. Fiechtner M, Ramp J, England B, Knudson MA, Little RR, England JD, et al. Affinity binding assay of glycohemoglobin by two-dimensional centrifugation referenced to hemoglobin Alc. Clin Chem 1992;38:2372–9.
3. Hortin GL, King C, Kopp J. Quantification of rhesus monkey albumin with assays for human microalbumin [Abstract]. Clin Chem 2000;46:A140-1.
4. Demers LM. New biochemical marker for bone disease: is it a breakthrough? [Editorial]. Clin Chem 1992;38:2169–70.
- Letter to the Editor:
5. Davey L, Naidoo L. Urinary screen for acetaminophen (paracetamol) in the presence of N-acetylcysteine [Letter]. Clin Chem 1993;39:2348–9.
- Book Chapter:
6. Rifai N, Warnick GR. Lipids, lipoproteins, apolipoproteins, and other cardiovascular risk factors. In: Burtis CA, Ashwood ER, Bruns DE, editors. Tietz textbook of clinical chemistry and molecular diagnostics. 4th Ed. St. Louis (MO): Elsevier Saunders; 2006. p. 903-81.
7. Haughton MA. Immunonephelometric measurement of vitamin D binding protein [MAppSci thesis]. Sydney, Australia: University of Technology, 1989:87pp.
- Books and Monographs (serial volumes should be treated as journals):
8. Harrell FE Jr. Regression modeling strategies. New York (NY): Springer; 2001.
9. Bailar JC III, Mosteller F, editors. Medical uses of statistics. 2nd Ed. Boston (MA): NEJM Books; 1992:449 p.
- Published Ahead of Print:
10. Milbury CA, Li J, Makrigiorgos GM. PCR-based methods for the enrichment of minority alleles and mutations. [Epub ahead of print] Clin Chem February 6, 2009 as doi:10.1373/clinchem.2008.113035.
11. Castelli WP. Lipids, risk factors and ischaemic heart disease. Atherosclerosis 1996;124 Suppl:S1-9.
- Internet Source:
12. American Association for Clinical Chemistry. AACC continuing education. http://www.aacc.org/education-and-career/continuing-education (Accessed June 2016).
- Clinical Chemistry Trainee Council Webcasts and Pearls of Laboratory Medicine:
14. Browning T. Vitamin D. April 2012. Available from: http://www.traineecouncil.org/pearl (Clinical Chemistry Trainee Council, Pearls of Laboratory Medicine).
Tables are considered text. They should appear embedded as part of the submission directly following the reference section. Each table should appear on an individual page. Manuscripts will be returned to authors if the tables are uploaded as separate table files. (Manuscripts will not be returned for this reason if tables have been uploaded as supplemental data or if they are to be considered figures, in the special circumstances described below.)
Each table should be clearly labeled and numbered consecutively with Arabic numerals (Table 1, Table 2, etc.). The abbreviations used must be defined. As with the text, reporting of concentration units consists of analyte concentrations expressed in the text in the traditional mass unit (mg/dL, ng/ml, and so forth) followed by the SI unit in parentheses.
Tables should not be divided into parts. Separate parts (Table 1A, Table 1B, etc.) will be considered separate tables and will count toward your overall table/figure count.
Table captions should be limited to 60 words.
Each column of an individual table must have a heading and be clearly defined. Indicate explanatory footnotes with superscript lowercase italic letters in alphabetical order.
Tables will be converted into a standard format for publication that will not include color. Large or complex tables or tables that include graphic elements should be submitted as figures or as supplemental data for online publication only. The Editor may choose to make any table supplemental as he/she deems necessary.
If a table has been published previously, acknowledge the original source in the table caption. You must obtain written permission from the copyright holder to reproduce the table and upload this permission as supplemental data. Please specify whether the table has been exactly reproduced or adapted from the original source, and provide a copy of the original table if it has been adapted. Even if the table has been modified, it may still require a permission. Any costs associated with table permissions will be borne by the author. Contact the editorial office at email@example.com if you are not sure whether permission is needed.
Figure captions and sub-captions must be listed together on an individual page directly following the tables or the references if the submission does not include tables. Each figure requires a figure caption and should be clearly labeled (Figure 1, Figure 2, etc.). Multi-panel figures and figures with parts (a, b, c, etc.), should be distinctively labeled (Figure 1A, Figure 1B, Figure 2A, etc.).
Figure captions should be limited to 60 words.
If a figure has been published previously, acknowledge the original source in the figure caption. You must obtain written permission from the copyright holder to reproduce the figure and upload this permission as supplemental data. Please specify whether the figure has been exactly reproduced or adapted from the original source, and provide a copy of the original figure if it has been adapted. Even if the figure has been modified, it may still require a permission. Any costs associated with figure permissions will be borne by the author. Contact the editorial office at firstname.lastname@example.org if you are not sure whether permission is needed.
All figures must be uploaded separately as image files in Tagged Image File Format (.TIFF) or Encapsulated Postscript (.EPS). Microsoft Power Point (.PPT) is also acceptable; however, the graphics must contain embedded fonts with one image per slide, one slide per file. Each image should have a resolution of 600 dots-per-inch (dpi). More detailed specifications can be found on our print publication vendor’s page at CADMUS Digital Art Support.
The submission system is designed to retrieve the manuscript file and separate image file(s) and combine or merge the files into an individual Portable Document Format (.PDF) for reviewing purposes. It is the responsibility of the author to verify the quality of the image file(s) after the conversion to PDF. It may be necessary to alter the individual image file(s) to ensure the content is not lost or misconstrued in the merged PDF.
Submissions will be returned to authors if the figures are embedded within the manuscript file and not uploaded separately or if the figures have become illegible in the merged PDF.
Do not place unnecessary graphics, such as borders, in or around your figure. Pay particular attention to the quality of the lines, symbols, and patterns. Published figures are reduced to 1 column (85mm) or 2 columns (176 mm) in width. If, at that width, the figure symbols or lettering are not clear, you will need to increase the font size. Letters should be 8-10 points when reduced, and subscripts no less than 6 points. Initial capitals and lower case letters and a medium (not bold) sans serif font are required. European PI, Helvetica, Mathematical PI, Times Roman, and Symbol fonts are Type 1 PostScript fonts supported by our printer for the creation of digital art figures.
The x-axis and y-axis should be clearly labeled, and the units of measurements given. This includes using decimal points instead of commas, italicizing species or gene symbols, and using U.S. English.
The costs of publishing color illustrations in print will be borne by the author. Costs are $1500 for the first figure and $500 for each subsequent figure, or parts of figures. Upon acceptance, authors will be billed for the color costs unless a request to print figures in black and white is received via cover letter or e-mail. Color versions of figures may be provided for publication in the online Journal at no extra charge. Please note your color preference and/or your agreement to pay for color printing in your cover letter. If black and white printing is requested, color figures alone should still be submitted to the Journal. The figures will be converted to grayscale by the printer. Authors should not attempt to convert the figures or submit both color and grayscale versions.
Figures or tables too large for print, manuscript material that exceeds the limitation for the specific submission type, or appendices should be submitted for online publication only. These files should be marked and uploaded separately as supplemental files during submission and should be referenced within the text as supplemental data (i.e., "See Supplemental Table 1", "See Supplemental Figure 1", etc.). Supplemental files must be labeled consecutively (i.e., Supplemental Table 1, Supplemental Table 2, Supplemental Figure 1, Supplemental Figure 2, etc.).
When labeling your files and referencing them within the main text, please keep in mind the preferred naming conventions for supplements. “Supplemental” is preferred over “Supplementary,” and the word “Data” is not necessary in table or figure titles (i.e., “Supplemental Table 1,” not “Supplemental Data Table 1” or “Supplementary Table 1”). If all supplemental materials are contained in a single file, that file should be referred to as "Supplemental Data."
Captions for the supplemental data should be uploaded as a separate supplemental file or embedded within the supplemental data/table/figure file. Do not include the supplemental captions in your manuscript file.
Please be advised, supplemental data are permitted for Article, Inspiring Minds, Mini-Review, Review, and Special Report submissions only. Manuscripts of all other types with supplemental data will be returned to authors.
Supplemental data will be reviewed as part of the manuscript and will be evaluated for its importance and relevance; however, it should not appear in the “Peer-reviewed PDF” file created by the submission system.
If accepted and posted online, the supplemental data will be referenced in the text of the print article directing readers to the URL of the website.
Clinical Chemistry uses the Bench>Press™ (B>P) manuscript submission, tracking, review, and publishing system, developed by Stanford University Libraries' HighWire Press.
For user convenience and accessibility, B>P converts uploaded manuscript files to Adobe Portable Document Format (PDF). Adobe Acrobat Reader is required to view these files and is available at no cost. Click the following link to download: http://www.adobe.com/products/acrobat/readstep2.html
B>P uses a series of pages, presented one at a time, to guide the author through the submission process. For help during regular business hours, contact Clinical Chemistry via e-mail at email@example.com.
Please see FAQs at http://submit.clinchem.org/journals/clinchem/forms/registration_faq.pdf for more extensive help.
Before submitting a manuscript or review of a manuscript, you must register with our manuscript submission and tracking system. Register at http://submit.clinchem.org/cgi/registration.
After accessing the registration page, you will need to verify your e-mail address. If there is an existing account with an old e-mail address, do not create a new account with a different e-mail address. Simply access the account with the out-of-date e-mail address, and use the system to update/change your e-mail address.
Always use the same e-mail when accessing the system. Multiple e-mail addresses will cause repeated registrations and the creation of multiple accounts, which could lead to future system access problems.
NOTE: If you have used other Bench>Press journals, you must use the same e-mail address and password to register with Clinical Chemistry. Although all Bench>Press journals require the same e-mail address and password for access, this is the only shared information. You must be registered individually with each journal you are trying to access.
E-mail addresses, passwords, and other contact information can be modified at any time by clicking "Personal Info" from the gray navigation bar at the top of any page within the manuscript processing system.
Feel free to contact the Editorial Office via e-mail at firstname.lastname@example.org should you need assistance.
Please see FAQs at http://submit.clinchem.org/submission/submissionhelp for more extensive help.
All authors and reviewers must be registered with Clinical Chemistry. To register, go to http://submit.clinchem.org, and click the “Create a New Account” button to the left of the login screen. If you do not receive a request to create a password and answer a security question, you are most likely registered with Clinical Chemistry or another Bench>Press journal. Clinical Chemistry uses an online manuscript management system called Bench>Press. Bench>Press is used by hundreds of journals, all of which share the same registration system. If you have already registered with another Bench>Press journal, you do not need to repeat the registration process. You simply need to sign in with the same e-mail and password and complete a profile page for Clinical Chemistry.
If you can't remember with which journal(s) you registered, this information can be sent by clicking the "Send My Registration Details" button on the registration page.
No e-mail response after registering:
If you have registered and have not received a verification e-mail, this may be due to a spam blocking filter associated with your institutional server. You may need to manually register email@example.com so as to accept mail from Clinical Chemistry. Your Systems Manager should be able to help you with this problem.
If you are using Internet Explorer as your browser and are having trouble accessing pages, you might want to try the following:
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You may check to see if the site works properly by going to http://submit.clinchem.org/.
Please note that login information (e-mail and password) for the submission and review site will not be the same login information you use if you subscribe to the online journal.
Often, due to problems with the initial registration or infrequent use, an author may have two accounts listed. Multiple accounts lead to future system access problems and therefore must be merged.
If an author or reviewer suspects this is the problem, send a request with the preferred e-mail address, current contact information, and the suspected invalid e-mail address to the Clinical Chemistry editorial office at firstname.lastname@example.org.
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Bench>Press requires users to have their browser set to accept cookies in order to maintain their logged-in status throughout the system. A "cookie" is a message given to a browser by a server. The browser stores the message, and the message is sent back to the server each time the browser requests a page from the server.
If the user does not have cookies enabled, the user will be required to repeatedly sign in to the system.
Most browsers will allow the user to manually alter the cookie settings from the Tools or Internet Options bar.
The Area of Expertise list was developed to help editors choose reviewers who possess specific knowledge in a given area.
Our tracking system has been set to allow this page to appear---as a gentle reminder---until the reviewer has selected at least one item on the list. As soon as the reviewer selects a topic and saves it, it will no longer appear.
Changing these areas of expertise or adding more detailed information can be accomplished by simply logging into http://submit.clinchem.org/ at any time and clicking the Personal Info area at the top of the page.
On the lower right side of the page, the user will find "Expertise Terms: Edit Expertise Terms." Click on this link and change the data accordingly.
Receiving a conversion error means that conversion of your manuscript to PDF format has failed.
Invalid file types are the most common cause of conversion failure. Be sure your file names end with extensions appropriate to the file type (i.e. ".doc", ".tif" or ".eps"). Mac computers generally leave off the file type extension and it must be added manually.
Formats that are not supported include the following: Bitmap (.bmp), PICT (.pict), Excel (.xls - Excel tables can be embedded in word processing documents), Photoshop (.psd), Canvas (.cnv) and CorelDRAW (.cdr). Multi-slide PowerPoint files (.ppt). If any of these have been used to create your file, you will need to convert the file to an acceptable file format for submission in order for the files to convert properly.
Large or numerous files may slow the conversion process of submission, sometimes resulting in a system "time out" or conversion failure. It may be appropriate to upload and wait for the conversion of an individual file before proceeding with the remaining files. The Bench>Press submission and tracking system has limits of how much data can be uploaded at one time. Generally most files become unwieldy when they pass the 1 MB (megabyte) mark.
- 1000 Bytes (B) = 1 Kilobyte (KB)
- 1000 Kilobytes (KB) = 1 Megabyte (MB)
- 1000 Megabytes (MB) = 1 Gigabyte (GB)
Empty HTML references field:
You may find that your HTML references section is empty. This can be remedied by including the heading "References" before the references section in your paper.
HTML references cannot be edited directly; any changes must be made by re-uploading your manuscript file during the proofing stage.
In addition, uploading a PDF file as your manuscript source file will prevent the references from parsing to the Clinical Chemistry HTML reference window.
Upon acceptance, all authors are required to read and sign the Copyright Transfer Agreement. Each author will be invited via e-mail to sign a statement confirming that the manuscript does not contain material for which publication would violate any copyright or other personal or proprietary right of any person or entity. U.S. Federal employees will need to be identified. Each author must be registered with our online submission system to access, read, and electronically sign the copyright agreement.
Manuscripts will be held until all copyrights are received. In the event that copyrights are not received, the manuscript will not be published.
Manuscripts will not be prohibited from publication solely on the basis of a web-posting of a talk at a medical or scientific meeting that presents all or part of the content of the submitted manuscript.
Authors are expected to retain – for a minimum of 1 year after publication – the raw data from laboratory or clinical studies and to present these data upon request of the Editor if the data are contested.
Authors are expected to identify to the Editor any other manuscripts (in print, accepted, have been submitted, in preparation) that relate to the submitted manuscript, especially if any patients or results are described in both.
Questions related to the possibility of perceived redundant publication or fragmentation of results should be directed to the Editor.
Manuscripts published in Clinical Chemistry reflect the individual views of their authors and, in the absence of a statement to the contrary, not the views of the institutions with which the authors are affiliated. The contents of advertisements or articles are not to be construed as official statements, evaluations, or endorsements by the Editor or the American Association for Clinical Chemistry.
Clinical Chemistry is copyrighted by the AACC. Permission to reproduce copyrighted material for scholarly or commercial use can be arranged through the AACC office in Washington, DC.
900 Seventh Street, NW
Washington, DC 20001
Phone: 800-892-1400 or 202-857-0717
Reprints of papers published in Clinical Chemistry can be obtained at any time in multiples of 100.
Authors will receive a reprint order form with their page proof or they can contact the Cenveo Reprint Department at 1-866-487-5625 or 410-943-3728.
Early Release is a service offered by Clinical Chemistry where authors' proofs of accepted articles are published online as they become available.
The proofs are available as PDFs, 3-5 weeks before their publication in print or in their final on-line format. The version posted ahead of print is an uncorrected page proof. Author corrections have not been made.
For current articles, click Clinical Chemistry Early Release.
900 Seventh Street, NW
Washington, DC 20001
(202) 833-4576 [FAX]
Sheehan Misko, Associate Director: email@example.com
Kristen Hauck, Assistant Managing Editor: firstname.lastname@example.org
Sarah Lake, Editorial Specialist: email@example.com
Patty Brady, Editorial Specialist: firstname.lastname@example.org
Erin Roberts, Editorial Specialist: email@example.com
Please include the corresponding author's e-mail address and the manuscript number on all correspondence.