The purposes of this study were to identify the factors that underlie assistive technology (AT) and to validate items to be used in an instrument to evaluate AT use. The study consisted of four phases. First, 99 items were developed though a comprehensive literature review. Second, the items were refined through three layers of review. Third, 1,467 respondents rated the results of the reviews. Fourth, exploratory factor analysis, and three confirmatory factor analyses (CFA) were employed to analyze the data. The results of the CFA were statistically significant (root mean square error of approximation [RMSEA] = 0.036, p = 0.00) with a total of 67 items across 8 factors (effectiveness, affordability and dependability, utility, external support, operations, longevity, discomfort, and compatibility).