The use of falls risk screening tools may aid in targeting fall prevention interventions in older individuals most likely to benefit. To determine the optimal physical or cognitive test to screen for falls risk in frail older people. This prospective cohort study involved recruitment from 213 day-care centers in Japan. The feasibility study included 3,340 ambulatory individuals aged 65 years or older enrolled in the Tsukui Ordered Useful Care for Health (TOUCH) program. The external validation study included a subsample of 455 individuals who completed all tests. Physical tests included grip strength (GS), chair stand test (CST), one-leg standing test (OLS), functional reach test (FRT), tandem walking test (TWT), 6-meter walking speed at a comfortable pace (CWS) and at maximum pace (MWS), and timed up-and-go test (TUG). The mental status questionnaire (MSQ) was used to measure cognitive function. The incidence of falls during 1 year was investigated by self-report or an interview with the participant's family and care staff. The most practicable tests were the GS and MSQ, which could be administered to more than 90% of the participants regardless of the activities of daily living status. The FRT and TWT had lower feasibility than other lower limb function tests. During the 1-year retrospective analysis of falls, 99 (21.8%) of the 455 validation study participants had fallen at least once. Fallers showed significantly poorer performance than non-fallers in the OLS (p = 0.003), TWT (p = 0.001), CWS (p = 0.013), MWS (p = 0.007), and TUG (p = 0.011). The OLS, CWS, and MWS remained significantly associated with falls when performance cut-points were determined. Logistic regression analysis revealed that the TWT was a significant and independent, yet weak predictor of falls. A weighting system which considered feasibility and validity scored the CWS (at a cut-point of 0.7 m/s) as the best test to predict risk of falls. Clinical tests of neuromuscular function can predict risk of falls in frail older people. When feasibility and validity were considered, the CWS was the best test for use as a screening tool in frail older people, however, these preliminary results require confirmation in further research. Copyright 2009 S. Karger AG, Basel.