Annals' Structured Manuscript Format

Annals style is to format research manuscripts with subheadings and elements as discussed below. See separate sections for Annals' style regarding guidelines and preference for specific study designs such as randomized controlled trials, preferences for methodology and statistics, and preferences for tables and figures.

Abstract Subheadings

Your abstract should be 250 words or less, and divided into the subheadings: Study hypothesis or Objective, Methods (include information on design, setting, participants, interventions, and main outcomes measured), Results, and Conclusions. In your results emphasize the magnitude of findings over test statistics, ideally including the size of effect and its confidence intervals for the principal outcomes.

Introduction Subheadings

The most effective introduction sections are less than 500 words, and concisely argue how the topic is new, scientifically important, and clinically relevant. All but the shortest introductions will benefit from separation into three subheaders:

• Background: Describe the circumstances or historical context that set the stage and led you to investigate the issue.
• Importance: Describe why your investigation is consequential. What are its potential implications? How does it relate to issues raised in the first paragraph? Why is this specific investigation the next logical step?
• Goals of This Investigation: Clearly state the specific research objective or hypothesis and your primary outcome measure.

Methods Subheadings

The Methods section should be organized with logical and sequential subheadings. The optimal subheading choices will vary with the analysis, but the following examples applicable to most clinical research:

• Study design and setting: Describe the study design using standard terms, and describe the study setting in a fashion that conveys characteristics that could affect the external validity (generalizibility) of the findings.
• Selection of Participants: Describe how participants were identified, screened, and enrolled. Remember to consider all participants including patients, providers, and outcome assessors, as appropriate. Describe specific inclusion and exclusion criteria.
• Interventions: Describe any interventions in sufficient detail to permit replication. Describe any blinding of subjects, providers, outcome assessors, or data analysts. Describe methods for determining whether the intervention was actually received.
• Methods and Measurements: Discuss how and when measurements were made. Discuss the precision and reliability of the measurements. How were spurious or missing measurements handled? Discuss who collected the data and how they collected it. Discuss how data were entered, checked, and processed.
• Outcomes: Describe the study's primary and secondary outcome measures, and if needed explain why they were chosen to address the study objective. When possible, use outcomes that have been previously validated, or provide evidence of your own efforts to validate the measure. Emphasize patient-centered outcomes (eg, pain, days off from work, death) over intermediate outcomes (eg, change in forced expiratory volume, change in asthma score).
• Analysis: Detail the primary analysis and specify any software that was used, including the name of the software and the company that produces it. Provide references for any non-routine analytic methods. If appropriate, detail sensitivity analyses that explore how results change when assumptions about the investigation are modified.

Results Subheadings

The Results section should be organized with logical and sequential subheadings. The optimal subheading choices will vary with the analysis, but the following examples are applicable to most clinical research:

• Characteristics of study subjects: Account for all subjects, beginning with the number of subjects who could have participated in the study.
• Main results: Present the results in a logical, sequential order that parallels the organization of the Methods section. Present as much data as possible at the level of the unit of analysis, graphically if possible. Emphasize the magnitude of findings over test statistics, ideally using size of effect and associated confidence intervals for each outcome. Describe sensitivity analyses if appropriate.

Limitations

Explicitly discuss the limitations of your study, including threats to the internal and external validity of your results. When possible, examine the magnitude and direction of each bias and how it might affect the interpretation of results.

Discussion

Briefly summarize the results and how they relate to your area of investigation. Consider only those published articles directly relevant to interpreting your results and placing them in context. Do not stress statistical significance over clinical importance. Avoid extrapolation to populations or conditions that you have not explicitly studied in your investigation. Avoid claims about cost or economic benefit unless a formal cost-effectiveness analysis was presented in the Methods and Results sections. Do not suggest "more research is needed" without stating what the specific next step is.

Optionally, you may include a paragraph "In retrospect, . . ." to candidly discuss what you would do differently if given the opportunity to repeat the study, so others can learn from your experience.

Do not use a separate conclusion section, but instead append it as the last paragraph of the Discussion beginning something like: "In summary, . . ." Take care that the conclusion is restricted to what can be justified by your experimental results.

Return to home page.