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

Background: The adaption of 'evidence-based healthcare' requires that pract itioners can identify and interpret findings from rigorous research with a view to introducing them into clinical practice. This, in turn, necessitate s the prior acquisition of skills in information retrieval and critical app raisal. Aim: To examine how the systematic retrieval and subsequent appraisal of re search might usefully inform clinical practice. Method: A community dietitian investigated the effect of vitamin C on the h ealing 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 ran domized controlled trials which were critically appraised and a critical co mmentary produced. Conclusion: There is insubstantial evidence to support use of a daily vitam in C supplement for healing pressure sores. Over 20 years' treatment of pre ssure sores has been found to be based on a single flawed study.