A critical guide to case series reports

Objective. Provide guidance to investigators and authors regarding appropriate conduct and reporting of case-series studies. Summary of Background Data. Evidence-based practice has provided a substantial contribution to advancing clinical science. Many study designs have been critically examined, and the quality of the research literature has improved. A common study design in musculoskeletal medicine is the case series: a description of the course of patients over time. Case series can provide valuable information as to: case definition, trend analyses regarding outcomes, and clues as to causation. Case series cannot be used to draw inferences regarding treatment effect. Methods. Examination of previous work on identification of characteristics of high quality study designs such as cohort studies; extending this work to case series. Results. We identified draft characteristics that good case series studies should address: clearly defined study question; well-described study population; well-described intervention; use of validated outcome measures; appropriate statistical analyses; well-described results; discussion/conclusions supported by the data presented; funding sources acknowledged. Conclusions. We propose these measures to authors and journal editors as one mechanism to improve the quality of the case series study.