Can physician's self‐estimates be used as a valid instrument to determine prescription frequencies of anti‐psoriatic drugs? Comparison of the results of a cross‐sectional study using self‐estimates with actual prescription behavior documented in a cohort study. (17th May 2013) - Nast, Alexander
ABSTRACT: Purpose: Physicians' self‐estimates of their own prescription behavior can be used as a tool to gather information on prescription frequencies. Self‐estimates as a tool for health‐care research on prescription frequencies need to be validated as a suitable method before it can be used widely. Methods: We performed a cross‐sectional study inviting all dermatologists in Berlin and Brandenburg to give self‐estimates of their own prescription behavior of anti‐psoriatic drugs. The results were compared with the results from a consecutive 8‐months cohort study with the same participants documenting their actual treatment choices during every visit of a psoriasis patient on a standardized documentation sheet. Differences between self‐estimates and documented prescription patterns were analyzed with respect to systemic anti‐psoriatic drugs and UV treatment. Results: Fifty‐one dermatologists participated. They documented an average of 91 patient visits each. Absolute differences between the self‐estimates and the documented actual prescription behavior ranged from −2.5% to 1.4% for systemic treatments. For psoralen plus ultravioloet A (PUVA) treatment, the absolute difference was 3.3% and for ultraviolet B (UVB) 4.7%. Conclusions: Self‐estimates were surprisingly exact. Self‐estimates may be suggested as one tool to assess prescription frequencies, but further studies are needed to confirm their validity. Copyright © 2013 John Wiley & Sons, Ltd.