[Evidence-based ambulatory dermatological treatment].

The evidence base for routine therapeutic decisions in dermatological out-patients was studied in a random sample of the case-notes from 115 out-patients. The evidence base of therapy prescribed when the diagnosis was ascertained was studied in literature searches in MEDLINE and EMBASE. Evidence was structured into primary evidence consisting of randomised controlled trials, and secondary evidence consisting of follow-up studies or applying trial results from clinical analogies, e.g. atopic and seborrheic dermatitis treatment. Randomised controlled trials could be found describing 38% (95% confidence interval: 30-47) of all treatments. Secondary evidence was found for 33% (24-41), while no evidence was found for 23% (16-31) of the given treatments. Approximately 75% of dermatological out-patient therapy is founded on scientific evidence spanning from randomised controlled trials to logical deduction about a given disease from an analogous clinical situation. The proportion of evidence based medicine in dermatological therapy therefore appears comparable to that of other fields of medicine.