The Validity and Reliability of Self-Reported Adherence to Using Offloading Treatment in People with Diabetes-Related Foot Ulcers

• Main Authors: Ababneh, A. (Author), Armstrong, D.G (Author), Edwards, H. (Author), Finlayson, K. (Author), Lazzarini, P.A (Author), Najafi, B. (Author), van Netten, J.J (Author)
• Format: Article
• Language: English
• Published: MDPI 2023
• Subjects: Activity monitors; adherence; Adherence; diabetic foot; Diabetic foot; Diseases; foot ulcer; Foot ulcer; offloading; Offloading; Reliability; self-report; Self-report; Test-retest reliability
• Online Access: View Fulltext in Publisher; View in Scopus

 Adherence to using offloading treatment is crucial to healing diabetes-related foot ulcers (DFUs). Offloading adherence is recommended to be measured using objective monitors. However, self-reported adherence is commonly used and has unknown validity and reliability. This study aimed to assess the validity and reliability of self-reported adherence to using removable cast walker (RCW) offloading treatment among people with DFUs. Fifty-three participants with DFUs using RCWs were included. Each participant self-reported their percentage adherence to using their RCW of total daily steps. Participants also had adherence objectively measured using dual activity monitors. After one week, a subset of 19 participants again self-reported their percentage adherence to investigate test–retest reliability. Validity was tested using Pearson’s r and Bland–Altman tests, and reliability using Cohen’s kappa. Median (IQR) self-reported adherence was greater than objectively measured adherence (90% (60–100) vs. 35% (19–47), p < 0.01). There was fair agreement (r = 0.46; p < 0.01) and large 95% limits of agreement with significant proportional bias (β = 0.46, p < 0.01) for validity, and minimal agreement for test–retest reliability (K = 0.36; p < 0.01). The validity and reliability of self-reported offloading adherence in people with DFU are fair at best. People with DFU significantly overestimate their offloading adherence. Clinicians and researchers should instead use objective adherence measures. © 2023 by the authors.