Reliability of the Pedar in-shoe system for plantar pressure measurement in diabetic patients with and without neuropathy: a prospective study

Background: The aim of this study was to evaluate within and between days' reliability of the Pedar in-shoe system (Novel GmbH, Munich, Germany) to measure plantar pressure in diabetic patients with and without neuropathy. Methods: Forty-seven diabetic patients were divided into diabetic without neuropathy, and with mild, moderate, and severe neuropathy groups based on Toronto Clinical Neuropathy Score. Plantar pressure measurement was taken twice a day to assess within the same day's reliability and after a mean of 7 days to evaluate between different days' reliability. Results: Intraclass correlation coefficients (ICC) analysis indicated excellent reliability (ICC >= 0.75) in tests within the same day in all groups. Mean pressure and pressure time integral showed excellent levels of ICC reliability in the tests between different days' in the diabetic group without neuropathy and with mild neuropathy (ICC >= 0.75) and fair-to-excellent in the diabetic group with moderate and severe neuropathy (ICC >= 0.40). Reliability of contact area between different days were excellent in all groups (ICC >= 0.75). Conclusions: The results indicated that the Pedar in-shoe system was a reliable measure of plantar pressure within the same day and between different days in diabetic patients with and without neuropathy. The level of reliability was altered with a change of the neuropathy severity.