Work Ability Decline Through Aging and Disability in Workers with Intellectual Disabilities: Validation of the PROLAB Tool

Background The growing number of older workers with intellectual disabilities highlights the need for specific tools to assess aging-related work ability decline in this population. Objectives This study validates PROLAB tool, which assesses Work Ability Decline for Aging and Disability (WADAD). It also describes this emerging phenomenon. Method PROLAB was administered to 481 workers aged between 23 and 67 years ( M = 50.62; SD = 7.94). Most were employed in Special Employment Centers (72.8%), performed physical jobs (74.4%), and worked full time (67.4%). The construct was validated through exploratory factor analysis. Reliability was assessed using Cronbach's alpha, and ANOVA analyzed the impact of personal and occupational variables on work ability decline. Results The final version comprises 46 items across three dimensions: job fit, social and behavioral functioning, and physical health. It explained 50.94% of the variance in frequency and 57.16% in intensity, showing high internal consistency (α = 0.95 and α = 0.97, respectively). Several significant associations of variables were found, but the degree of disability combined with the presence of associated disabilities provides the best explanation for WADAD. Conclusions Analysis of WADAD is essential for understanding the support needs of this group, especially regarding job fit, aging and retirement.