Objective: To evaluate psychometric properties of 16-item and 7-item Falls Efficacy Scale-International (FES-I) in people with multiple sclerosis (MS).

Methods: Validation and prospective cohort study. Methods: People with MS living in metropolitan areas. Methods: Community-dwelling people with MS (N=169; aged 21-73y) who were referred to Multiple Sclerosis Australia for physiotherapy assessment. Methods: Not applicable. Methods: FES-I scores and a range of sociodemographic, physical, and neuropsychological measures.

Results: The mean score for the 16-item FES-I was 34.9±11.2, and the mean score for the 7-item FES-I was 14.7±4.7. FES-I total scores were normally distributed: skewness of .35 (SEM=.19) for the 16-item and .47 (SEM .19) for the 7-item FES-I, indicating the absence of floor and ceiling effects. Internal reliability was excellent, with Cronbach's alpha values of .94 (16-item) and .86 (7-item). Rasch analyses indicated that the structure and measurement properties were better for the 7-item FES-I than for the 16-item FES-I. Construct validity of both scales was supported by sensitivity to group differences relating to demographic characteristics and fall-risk factors.

Conclusions: The findings indicate that both 16-item and 7-item versions of the FES-I provide valuable information about the fear of falling in people with MS. However, the 7-item version of FES-I has better psychometric properties in people with MS.