AMA Manual of Style - Stacy L. Christiansen, Cheryl Iverson 2020
Research Reports
Types of Articles
Effective communication of scientific information requires consideration of the content, intended message, audience, and article format. To facilitate effective communication, editors of biomedical journals and other scientific publications use various article types, formats, and sections. However, most articles in scientific journals usually can be classified into 1 of the following general categories: Research Reports, Reviews, Other Substantive Articles (ie, nonresearch, nonreview), Opinion Articles, Correspondence, and Other Articles). For example, in the JAMA Network journals, major articles are classified into 3 main categories: research, clinical review and education, and opinion. These journals also use the following categories online to help users search by article type: research, review, opinion, case report, news, and humanities.
Editors and journals should provide clear and consistent guidance to authors about article types and requirements for each, such as in the instructions for authors. For example, JAMA Network Instructions for Authors include a section on Categories of Articles, which provides detailed information about the description and requirements for each type of article published in the journal.1
1.1 Research Reports.
Articles that report the results of original research investigations are perhaps the most important types of articles published by scientific journals. These articles advance scientific knowledge and, in medical journals, help inform clinical practice and advance patient care. Journals often categorize reports that present data from scientific research as Original Investigations (or Original Articles, Research Reports, or a similar designation) to emphasize the new findings these articles communicate.
Subcategories of Research articles may have specific designations based on other criteria. For instance, the JAMA Network journals may use designations based on (1) the nature of the findings, such as Preliminary Communication to indicate articles that report preliminary findings and signal the need for further investigation; (2) the topic of the research, such as Caring for the Critically Ill Patient to identify research in a specific clinical or scientific area, or Less Is More, to identify studies on how overuse of medical care may result in harm and how less intervention may lead to better health; or (3) article length, such as Brief Report to designate short reports of original studies or novel reports that involve small studies, or Research Letters to designate focused concise reports published as Correspondence.
Research reports may involve a wide range of study designs and methods, including randomized clinical trials, other intervention studies, cohort studies, case-control studies, epidemiologic investigations, surveys, meta-analyses, cost-effectiveness analyses, decision analyses, screening studies, diagnostic test evaluations, prognostic models, genetic and genomic studies, laboratory investigations, case series, case reports, and other designs. Data and information included in research reports must be original and should be as timely and current as possible. See Box 1.1-1 for a list of common study types, descriptions, and requirements as used by the JAMA Network journals.
Research reports in biomedical journals generally follow a similar format that consists of the following sections: Title, Abstract, Introduction, Methods, Results, and Discussion, along with References, Tables and Figures, Article Information, Acknowledgments, online-only Supplemental content, and perhaps Multimedia content (see 2.5, Abstract, and 2.8, Parts of a Manuscript, Headings, Subheadings, and Side Headings, for guidance in preparing these sections). Some journals encourage use of reporting guidelines for research articles.2 For example, guidelines for reporting clinical trials (Consolidated Standards of Reporting Trials [CONSORT]), observational studies (Strengthening the Reporting of Observational Studies in Epidemiology [STROBE[), or meta-analyses (Preferred Reporting Items for Systematic Reviews and Meta-Analyses [PRISMA]) or for other types of studies help ensure that key details related to the specific study design, methods, and results are included in the article. Box 1.1-1 also includes reporting guidelines for each of the study types listed.
Box 1.1-1. Study Types, Descriptions, Requirements, and Reporting Guidelines1
Randomized Clinical Trial
A trial that prospectively assigns participants to intervention or comparison groups to study the cause-and-effect relationship between an intervention and a health outcome. Interventions include but are not limited to drugs, surgical procedures, devices, behavioral treatments, educational programs, dietary interventions, quality improvement interventions, process-of-care changes, and the like.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Randomized Clinical Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Data Sharing Statement
■Follow CONSORT Reporting Guidelines
Parallel-Design, Double-blind Trial
A randomized trial that prospectively assigns participants to 2 or more groups to receive different interventions. Participants and those administering the interventions are unaware of which intervention individual participants are receiving.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Randomized Clinical Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Data Sharing Statement
■Follow CONSORT Reporting Guidelines
Crossover Trial
A trial in which participants receive more than 1 of the treatments under investigation, usually in a randomly determined sequence, and with a prespecified amount of time (washout period) between sequential treatments.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Randomized Clinical Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Data Sharing Statement
■Follow CONSORT Reporting Guidelines
Equivalence and Noninferiority Trial
A trial designed to assess whether the treatment or intervention under study (eg, a new intervention) is no worse than an existing alternative (eg, an active control). In these trials, authors must prespecify a margin of noninferiority that is consistent with all relevant studies and within which the new intervention can be assumed to be no worse than the active control.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Randomized Clinical Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Data Sharing Statement
■Follow CONSORT Reporting Guidelines
Cluster Trial
A trial that includes random assignment of groups rather than individuals to intervention and control groups.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Randomized Clinical Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Data Sharing Statement
■Follow CONSORT Reporting Guidelines
Nonrandomized Controlled Trial
A trial that prospectively assigns groups or populations to study the efficacy or effectiveness of an intervention but in which the assignment to the intervention occurs through self-selection or administrator selection rather than through randomization. Control groups can be historic, concurrent, or both. This design is sometimes called a quasi-experimental design.
■3000-3500 words
■≤5 tables and/or figures, including CONSORT flow diagram
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Nonrandomized Controlled Trial”
■Trial registration and ID
■Trial protocol
■CONSORT checklist
■Follow TREND Reporting Guidelines
Trial Protocol
A document that describes the organization and plan for a randomized clinical trial, including the trial’s objective(s), design, methods, outcomes to be measured, and statistical analysis plan.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Subtitle should be “A Trial Protocol”
■Trial registration and ID
■Trial protocol
■Follow SPIRIT Reporting Guidelines
Meta-analysis
A systematic review that includes a statistical technique for quantitatively combining the results of multiple studies that measure the same outcome into a single pooled or summary estimate.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Subtitle should include “A Systematic Review and Meta-analysis”
■Follow PRISMA or MOOSE Reporting Guidelines
Cohort Study
An observational study that follows a group (cohort) of individuals who are initially free of the outcome of interest. Individuals in the cohort may share some underlying characteristic, such as age, sex, diagnosis, exposure to a risk factor, or treatment.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow STROBE Reporting Guidelines
Case-Control Study
An observational study designed to determine the association between an exposure and outcome in which study participants are selected by outcome. Those with the outcome (cases) are compared with those without the outcome (controls) with respect to an exposure or event. Cases and controls may be matched according to specific characteristics (eg, age, sex, or duration of disease).
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow STROBE Reporting Guidelines
Cross-sectional Study
An observational study of a defined population at a single point in time or during a specific interval in which exposure and outcome are ascertained simultaneously.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow STROBE Reporting Guidelines
Case Series
An observational study that describes a selected group of participants with similar exposure or treatment and without a control group. A case series may also involve observation of larger units, such as groups of hospitals or municipalities, as well as smaller units, such as laboratory samples.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow Reporting Guidelines
Economic Evaluation
A study using formal, quantitative methods to compare 2 or more treatments, programs, or strategies with respect to their resource use and expected outcomes. This includes cost-effectiveness, cost-benefit, and cost-minimization analyses.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow CHEERS Reporting Guidelines
Decision Analytical Model
A mathematical modeling study that compares consequences of decision options by synthesizing information from multiple sources and applying mathematical simulation techniques, usually with specific software. Reporting should address the relevant noncost aspects of the CHEERS guideline.
■3000-3500 words
■≤5 tables and/or figures
✵ ■50-75 references
■Structured abstract
■Key Points
■Follow CHEERS Reporting Guidelines
Comparative Effectiveness Research
A study that compares different interventions or strategies to prevent, diagnose, treat, and monitor health conditions to determine which work best for which patients and under what circumstances and which are associated with the greatest benefits and harms.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow ISPOR Reporting Guidelines
Genetic Association Study
A study that attempts to identify and characterize genomic variants that may be associated with susceptibility to multifactorial disease.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow STREGA Reporting Guidelines
Diagnostic/Prognostic Study
A prospective study designed to develop, validate, or update the diagnostic or prognostic accuracy of a test or model.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow STARD Reporting Guidelines or TRIPOD Reporting Guidelines
Quality Improvement Study
A study that uses data to define, measure, and evaluate a health care practice or service to maintain or improve the appropriateness, quality, safety, or value of that practice or service.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow SQUIRE Reporting Guidelines
Survey Study
A survey study includes a representative sample of individuals who are asked to describe their opinions, attitudes, or behaviors. Survey studies should have sufficient response rates (generally ≥60%) and appropriate characterization of nonresponders to ensure that nonresponse bias does not threaten the validity of the findings.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow AAPOR Reporting Guidelines
■Optional: Survey instrument as supplemental file
Qualitative Study
A study based on observation and interview with individuals that uses inductive reasoning and a theoretical sampling model and that focuses on social and interpreted, rather than quantifiable, phenomena and aims to discover, interpret, and describe rather than to test and evaluate. This includes mixed-methods studies that combine quantitative and qualitative designs in a sequential or concurrent manner.
■3000-3500 words
■≤5 tables and/or figures
■50-75 references
■Structured abstract
■Key Points
■Follow SRQR Reporting Guidelines or COREQ Reporting Guidelines