Why appraise the evidence? A case study of vitamin C and the healing of pressure sores

Abstract

Background: The adoption of 'evidence-based healthcare' requires that practitioners can identify and interpret findings from rigorous research with a view to introducing them into clinical practice. This, in turn, necessitates the prior acquisition of skills in information retrieval and critical appraisal. Aim: To examine how the systematic retrieval and subsequent appraisal of research might usefully inform clinical practice. Method: A community dietitian investigated the effect of vitamin C on the healing of pressure sores using skills acquired from a course on systematic reviews and critical appraisal. Results: A systematic search across a range of databases identified two randomized controlled trials which were critically appraised and a critical commentary produced. Conclusion: There is insubstantial evidence to support use of a daily vitamin C supplement for healing pressure sores. Over 20 years' treatment of pressure sores has been found to be based on a single flawed study.