HOW MUCH CHANGE IS TRUE CHANGE? THE MINIMUM DETECTABLE CHANGE OF THE BERG BALANCE SCALE IN ELDERLY PEOPLE

Objective: To determine the minimum detectable change at 95%, confidence for the Berg Balance Scale in a group of elderly people, undergoing physiotherapy rehabilitation. Design: Multi-centre, test-retest design. Subjects: Cross-sectional sample of convenience of people over 65 years (n=118) without a previous history of stroke, Parkinson's disease or recent hip arthroplasty. Raters: Physiotherapists working with elderly people, drawn from the Physiotherapy Research into Older People group, ranging in experience from newly qualified to 39 years qualified. Methods: Each participant was assessed using the Berg Balance Scale and again within 48 hours by the same physiotherapist. The minimum detectable change at 95%, was established. Results: A change of 4 points is needed to he 95%, confident that true change has occurred if a patient scores within 4556 initially, 5 points if they score within 35-44, 7 points if they score within 25-34 and, finally, 5 points if their initial score is within 0-24 on the Berg Balance Scale. Conclusion: A clinician with a working knowledge of these minimum detectable change values can be up to 95%, confident that a true change or not a true change in a patients' functional balance has occurred and can therefore alter their interventions accordingly to ensure quality, focused rehabilitation.