The predictive validity of the Braden Scale and the timing of assessment for optimal prediction of pressure sore development (PS) were studied in a nursing home population. Subjects (N = 102) over age 19, free of PS and admitted within the previous 72 hr, were randomly selected from consecutive admissions to a skilled nursing facility. Subjects were assessed for risk and skin condition every 48 to 72 hr for 4 weeks. Twenty-eight subjects (27.5%) developed a PS. A cut score of 18 used at the observation prior to the first recorded PS maximized prediction, producing a sensitivity of 79%, a specificity of 74%, a 54% predictive value of a positive test, 90% predictive value of a negative test, and 75% correct classification rate.