Background In an aging society, it is increasingly important to understand how assistive devices can be used by older people to maintain quality of life despite chronic disabilities. Assistive technology is a mainstay of physical therapist practice, but the potential for device use to affect psychosocial well-being is not yet understood at the population level.Objective The objective of this study was to develop a parsimonious indicator that can be used in population-based surveys to represent the effect of assistive technologies on quality of life for older people, separate from personal assistance.Design This study was a cross-sectional survey.Methods The methods used in this study were psychometric scale development and structural equation modeling.Results The results indicated that a parsimonious, valid, and reliable scale reflecting quality of life related to assistive device use can be created from 3 questions designed to measure improvements in safety, control, and participation due to technology. The findings also suggested that assistive technology may more effectively improve quality of life for people with greater levels of functional limitations.Limitations The data were derived from a cross-sectional survey conducted by telephone. The use of personal assistance, on average, was low; thus, the applicability to a population with more profound care needs has yet to be confirmed.Conclusions Determining the broader impact of assistive technology on quality of life with population-level measures may provide insight into how best to leverage technologies to prevent dependence in aging adults.