An evaluation of vignettes for predicting variation in the quality of preventive care

Clinical vignettes offer an inexpensive and convenient alternative to the benchmark method of chart audits for assessing quality of care. We examined whether vignettes accurately measure and predict variation in the quality of preventive care.

We developed scoring criteria based on national guidelines for 11 prevention items, categorized as vaccine, vascular-related, cancer screening, and personal behaviors. Three measurement methods were used to ascertain the quality of care provided by clinicians seeing trained actors (standardized patients; SPs) presenting with common outpatient conditions: 1) the abstracted medical record from an SP visit; 2) SP reports of physician practice during those visits; and 3) physician responses to matching computerized case scenarios (clinical vignettes).

Three university-affiliated (including 2 VA) and one community general internal medicine clinics.

Seventy-one randomly selected physicians from among eligible general internal medicine residents and attending physicians.

Physicians saw 480 SPs (120 at each site) and completed 480 vignettes. We calculated the proportion of prevention items for each visit reported or recorded by the 3 measurement methods. We developed a multiple regression model to determine whether site, training level, or clinical condition predicted prevention performance for each measurement method. We found that overall prevention scores ranged from 57% (SP) to 54% (vignettes) to 46% (chart abstraction). Vignettes matched or exceeded SP scores for 3 prevention categories (vaccine, vascular-related, and personal behavior). Prevention quality varied by site (from 40% to 67%) and was predicted similarly by vignettes and SPs.

Vignettes can measure and predict prevention performance. Vignettes may be a less costly way to assess prevention performance that also controls for patient case-mix.