Inter-rater reliability of hand muscle strength, dexterity, function, joint mobility and sensory threshold assessments in individuals with type 2 Diabetes Mellitus in central part of Kerala, India

Background: Type 2 Diabetes Mellitus (T2DM) often leads to musculoskeletal complications affecting hand strength, dexterity, and function. Reliable assessment tools are essential for early detection and management of hand dysfunction, but inter-rater reliability in this population remains underexplored. Aim: To determine the inter-rater reliability of hand muscle strength, dexterity, function, joint mobility, and sensory threshold assessments in individuals with T2DM in central Kerala, India. Methods: Eighteen adults with T2DM were evaluated by two physiotherapists using standardized tools including hand-held dynamometer, pinch gauge, nine-hole peg test, box and block test, Indian-Cochin Hand Function Scale, goniometry, and Semmes Weinstein monofilaments. Inter-rater reliability was analyzed using intra-class correlation coefficients (ICC). Results: Inter-rater ICC values ranged from 0.71 to 0.99, indicating moderate to excellent reliability across all hand assessments. The highest reliability was observed for sensory threshold (ICC = 0.99) and hand function score (ICC = 0.95). Conclusion: The study confirms moderate to excellent inter-rater reliability of hand assessment tools in individuals with T2DM. These findings support their clinical use in physiotherapy for early detection and management of diabetic hand dysfunction.