Effectiveness of a Physical Activity Intervention for Pre-frail Older Adults With Chronic Pain.

Design: Randomized controlled, pragmatic clinical trial with two groups and 3 months follow-up. Unit of randomization: Patient. Unit of analysis: Patient. Setting: A Primary Health Care Center in the Spanish Autonomous Community of Madrid. Population: Pre-frail patients aged 65 years or more with chronic pain. Intervention: Multicomponent structured physical exercise program. Control group: Usual care. Variables: Perceived Health Related Quality of Life (EuroQol 5D-5L), Pain Intensity (Visual Analogue Scale), Frailty (SHARE-Frailty Index), Physical Performance (Short Physical Performance Battery, SPPB), Depression (Yesavage). Analysis: Mean change differences after 3 months in EQ5D dimensions between groups with CI 95%. Mean differences or proportion differences will be calculated according to variable characteristics between groups with appropriate statistical test.