Statistical Methods

SYSTEMATIC REVIEWS AND META-ANALYSES OF RANDOMISED CONTROLLED TRIALS

Please report these in accordance with the QUOROM (Quality of Reporting of Meta-analyses) statement (Moher D, Cook DJ, Eastwood S, Olkin I, Rennie D, Stroup DF, for the QUOROM Group. Improving the quality of reports of meta-analyses of randomised controlled trials: the QUOROM statement. Lancet 1999; 354:1896-1900. www.thelancet.com)

Please provide the following, as described in the QUOROM statement:

• Nine subheaded sections in the main text of the paper
• A flow chart (fig 1) showing the progress of trials through the review
• A checklist for editors and reviewers (not for publication) showing that you have described 21 key points in your report

We may choose not to use all of the subheadings in the published version of the paper for reasons of readability.

The structured abstract should have these sections: objectives, data sources, review methods, results, and conclusions.

STUDIES OF DIAGNOSTIC ACCURACY

Please report these in accordance with the STARD (Standards for Reporting of Diagnostic Accuracy) initiative. See:

Bossuyt PM, Reitsma JB, Bruns DE, Gatsonis CA, Glasziou PP, Irwig LM, Lijmer JG, Moher D, Rennie D, de Vet HCW. Towards complete and accurate reporting of studies of diagnostic accuracy: the STARD initiative.BMJ 2003;326:41-4  and http://www.consort-statement.org/stardstatement.htm

QUALITATIVE RESEARCH

These reports may be difficult to fit into the IMRAD (Introduction, Methods, Results and Discussion) format for original research papers. You may find that presenting the results and discussion together, theme by theme, makes most sense: this is fine, but please ensure that the structured abstract matches the layout of the text.

You may use direct quotes from participants in the text, but grouping them in boxes may allow you to keep the text within our limit of 2000 words, as long as this does not destroy the narrative of the paper.

Please label different participants' quotes with numbers or other titles so that readers can determine whether a range of people has been quoted.

The IJM's editors use a checklist to appraise qualitative research papers.

See Qualitative research checklist

ECONOMIC EVALUATIONS

If you submit a paper reporting an economic evaluation please ensure that it follows the IJM's guidelines. These are grouped in 10 sections under three headings: study design, data collection, and analysis and interpretation of results.

See Guidelines for authors and peer reviewers for economic submissions to the journal

See Economic evaluations checklist

EVALUATING EDUCATIONAL INTERVENTIONS

Many IJM readers may not be familiar with methodologies used to evaluate educational interventions.

Two crucial factors in good studies are that:

• the educational rationale behind the intervention is made explicit
• that the evaluation is planned in advance.

With a group of expert advisers from medical education the IJM has produced guidelines to use when reviewing original papers that describe educational innovations.

The guidelines are intended for authors, editors, reviewers, and readers.

The current guidelines are provisional: we have no doubt that they can be improved, and are seeking views on how to do this.

See Guidelines for evaluating articles on educational interventions