Statistical testing alone and estimation plus testing: Reporting study outcomes in biomedical journals

Systematic review and meta-analyses of studies analysing instructions to authors from 1987 to 2017

To gain insight into changes of scholarly journals' recommendations, we conducted a systematic review of studies that analysed journals' Instructions to Authors (ItAs). We summarised results of 153 studies, and meta-analysed how often ItAs addressed: 1) authorship, 2) conflicts of interest, 3) data sharing, 4) ethics approval, 5) funding disclosure, and 6) International Committee of Medical Journal Editors' Uniform Requirements for Manuscripts. For each topic we found large between-study heterogeneity. Here, we show six factors that explained most of that heterogeneity: 1) time (addressing of topics generally increased over time), 2) country (large differences found between countries), 3) database indexation (large differences found between databases), 4) impact factor (topics were more often addressed in highest than in lowest impact factor journals), 5) discipline (topics were more often addressed in Health Sciences than in other disciplines), and 6) sub-discipline (topics were more often addressed in general than in sub-disciplinary journals).

Issues affecting the level of prosthetics research evidence: Secondary analysis of a systematic review

BACKGROUND

Systematic reviews of scientific literature are valuable sources of synthesized knowledge. Systematic review results may also be used to inform readers about challenges inherent to an area of research, guide future research efforts, and facilitate improvements in evidence quality.

OBJECTIVES

To identify methodological issues that affected the overall level of scientific evidence reported in a contemporary systematic review and to offer suggestions for enhancing publications' contribution to the overall evidence.

STUDY DESIGN

Secondary analysis of a systematic review.

METHODS

Publications included in a systematic review related to microprocessor-controlled prosthetic knees were analyzed with respect to established methodological quality criteria. Common issues were identified and discussed.

RESULTS

Internal validity was commonly affected by variable comparison conditions, limited justification of accommodation time, potential fatigue and learning effects, lack of blinding, small sample sizes, limited evidence of measurement reliability, subject attrition, and limited descriptions of selection criteria. Similarly, external validity was affected by limited descriptions of the study sample, indeterminate representativeness, and suboptimal description of the interventions.

CONCLUSION

Results suggest that efforts to address methodological limitations, educate evidence consumers, and improve research reporting are needed to advance the quality and use of evidence in the field of prosthetics.

CLINICAL RELEVANCE

Critical analysis of the strengths and limitations of publications included in a systematic review can inform evidence consumers and contributors about challenges inherent to a field of research. Results of this analysis suggest that efforts to address identified limitations are needed to enhance the overall level of prosthetics evidence.