Assessing concerns about falling: a comparison of telephone-based and face-to-face FES-I interviews in older adults.

BACKGROUND: Concerns about falling (CaF) are commonly assessed using the Falls Efficacy Scale-International (FES-I), but telephone versus face-to-face interviews may influence responses. The objective of this secondary paired method-comparison analysis was to assess agreement between telephone and face-to-face FES-I total scores in older adults and to explore whether the two administration modes differed at the total-score and item levels. METHODS: Data were drawn from the FEARFALL study, a longitudinal randomized controlled trial on stress and functional health in older adults with CaF. FES-I scores of 123 participants aged 70 years and older were collected via both telephone and face-to-face interviews. Differences in total scores, item-level differences, and regression models were analyzed to identify potential influencing factors. RESULTS: FES-I scores obtained during the telephone-first assessment were lower than those obtained at the subsequent face-to-face assessment (p < .001; d = -0.34). Agreement between the two modes was moderate to good (ICC = 0.67). In addition, the two assessment modes showed a high correlation (r = .71) with heterogeneity at the item level. Three items showed significant deviations (Item 4: "bathing/showering", padj = 0.007, d = 0.36; Item 10: "answer telephone", padj = 0.005, d = 0.34; Item 14: "uneven ground" padj = 0.015, d = 0.32). Age was significantly associated with mode-related score differences (B = -0.326, 95% CI [-0.58, -0.07], p = .013). CONCLUSION: The telephone FES-I may be suitable for group-level comparisons and large-scale screenings. However, the interchangeability of telephone and face-to-face interview for individual clinical use remains uncertain. Since telephone assessment was always performed first and the time interval between assessments varied, the observed differences cannot be attributed to administration mode alone. Further studies specifically designed to compare administration modes are needed. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00029171), registered 22 July 2022.