Validating a fear-of-falling-related activity avoidance scale in lower limb prosthesis users

Noah J Rosenblatt; Matthew J Major; Bobak Manesh; Kristin Schneider; Steven A Miller

doi:10.1002/pmrj.13063

Validating a fear-of-falling-related activity avoidance scale in lower limb prosthesis users

PM R. 2023 Aug 26:10.1002/pmrj.13063. doi: 10.1002/pmrj.13063. Online ahead of print.

Authors

Noah J Rosenblatt¹, Matthew J Major^{2

3

4}, Bobak Manesh¹, Kristin Schneider⁵, Steven A Miller⁵

Affiliations

¹ Center for Lower Extremity Ambulatory Research (CLEAR) at the Dr. William M. Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA.
² Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois, USA.
³ Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, USA.
⁴ Jesse Brown VA Medical Center, Chicago, Illinois, USA.
⁵ Psychology Department, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois, USA.

PMID: 37632836
PMCID: PMC10895070 (available on 2025-02-26)
DOI: 10.1002/pmrj.13063

Abstract

Background: Limited available data suggest that fear of falling (FoF) may be common among lower limb prosthesis users (LLPUs) and associated with negative rehabilitation outcomes. The impact of FoF on outcomes may be exacerbated when fear leads to self-imposed declines in activity. There is a need to identify the validity of fear-of-falling-related activity avoidance scales in LLPUs.

Objective: To evaluate the convergent, discriminant, and known-group construct validity of the modified Survey of Activities and FoF in the Elderly (mSAFE) for LLPUs. Secondarily, we sought to determine if the mSAFE scale could be reduced without losing information regarding construct validity.

Design: Online survey.

Setting: Not applicable.

Participants: Fifty-nine persons with unilateral or bilateral amputation at the transtibial or transfemoral level, with ≥6 months experience using a definitive prosthesis for activities other than transfers.

Intervention: Participants completed an online survey that consisted of the mSAFE and questions to assess FoF (yes/no), fear-of-falling-related activity avoidance (yes/no), as well as previously validated scales capturing related and unrelated constructs. T-tests were used to compare mSAFE score between yes/no respondents for known-group construct validity. Correlations between mSAFE and previously validated surveys assessed convergent and discriminant validity. Analyses were repeated on a reduced number of mSAFE items following a redundancy analysis.

Main outcome measures: Not applicable.

Results: Significant correlation coefficients of |0.440-0.825| were found for convergent validity with evidence of known-group construct validity (p < .021 for all comparisons). There was evidence for discriminant validity, with non-significant associations for two-of-three correlations. Results from validity analyses for a shortened 6-item mSAFE were similar to that for the full scale.

Conclusion: This study provided initial evidence regarding validity of the mSAFE as a measure to assess fear-of-falling-related activity avoidance in LLPUs. A 6-item scale may be appropriate if the full scale would be taxing or time-consuming.

Abstract

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