Research articles

Guideline word limit: 4 000 words

Research articles describe the background, methods, results and conclusions of an original research study. The article should contain the following sections: introduction, methods, results, discussion and conclusion, and should include a structured abstract (see below). The introduction should be concise – no more than three paragraphs – on the background to the research question, and must include references to other relevant published studies that clearly lay out the rationale for conducting the study. Some common reasons for conducting a study are: to fill a gap in the literature, a logical extension of previous work, or to answer an important clinical question. If other papers related to the same study have been published previously, please make sure to refer to them specifically. Describe the study methods in as much detail as possible so that others would be able to replicate the study should they need to. Results should describe the study sample as well as the findings from the study itself, but all interpretation of findings must be kept in the discussion section, which should consider primary outcomes first before any secondary or tertiary findings or post-hoc analyses. The conclusion should briefly summarise the main message of the paper and provide recommendations for further study.

Select figures and tables for your paper carefully and sparingly. Use only those figures that provided added value to the paper, over and above what is written in the text.

Do not replicate data in tables and in text .

Structured abstract

  • This should be 250-400 words, with the following recommended headings:
    • Background: why the study is being done and how it relates to other published work.
    • Objectives: what the study intends to find out
    • Methods: must include study design, number of participants, description of the intervention, primary and secondary outcomes, any specific analyses that were done on the data.
    • Results: first sentence must be brief population and sample description; outline the results according to the methods described. Primary outcomes must be described first, even if they are not the most significant findings of the study.
    • Conclusion: must be supported by the data, include recommendations for further study/actions.
  • Please ensure that the structured abstract is complete, accurate and clear and has been approved by all authors.
  • Do not include any references in the abstracts.

Here is an example of a good abstract.


Main article

All articles are to include the following main sections: Introduction/Background, Methods, Results, Discussion, Conclusions.

The following are additional heading or section options that may appear within these:

  • Objectives (within Introduction/Background): a clear statement of the main aim of the study and the major hypothesis tested or research question posed
  • Design (within Methods): including factors such as prospective, randomisation, blinding, placebo control, case control, crossover, criterion standards for diagnostic tests, etc.
  • Setting (within Methods): level of care, e.g. primary, secondary, number of participating centres.
  • Participants (instead of patients or subjects; within Methods): numbers entering and completing the study, sex, age and any other biological, behavioural, social or cultural factors (e.g. smoking status, socioeconomic group, educational attainment, co-existing disease indicators, etc)that may have an impact on the study results. Clearly define how participants were enrolled, and describe selection and exclusion criteria.
  • Interventions (within Methods): what, how, when and for how long. Typically for randomised controlled trials, crossover trials, and before and after studies.
  • Main outcome measures (within Methods): those as planned in the protocol, and those ultimately measured. Explain differences, if any.


  • Start with description of the population and sample. Include key characteristics of comparison groups.
  • Main results with (for quantitative studies) 95% confidence intervals and, where appropriate, the exact level of statistical significance and the number need to treat/harm. Whenever possible, state absolute rather than relative risks.
  • Do not replicate data in tables and in text.
  • If presenting mean and standard deviations, specify this clearly. Our house style is to present this as follows:
  • E.g.: The mean (SD) birth weight was 2 500 (1 210) g. Do not use the ± symbol for mean (SD).
  • Leave interpretation to the Discussion section. The Results section should just report the findings as per the Methods section.


Please ensure that the discussion is concise and follows this overall structure – sub-headings are not needed:

  • Statement of principal findings
  • Strengths and weaknesses of the study
  • Contribution to the body of knowledge
  • Strengths and weaknesses in relation to other studies
  • The meaning of the study – e.g. what this study means to clinicians and policymakers
  • Unanswered questions and recommendations for future research


This may be the only section readers look at, therefore write it carefully. Include primary conclusions and their implications, suggesting areas for further research if appropriate. Do not go beyond the data in the article.