A confirmatory factor analysis of the fitness of adults with intellectual disabilities

To test whether a new model including nine variables can be used to test the fitness of adults with intellectual disabilities.

This is a cross-sectional study involving 445 adults aged 18-42 recruited during the Spanish Special Olympics. Confirmatory factor analysis (CFA) was used to test the goodness-of-fit of four latent variables: flexibility, strength, balance and cardiorespiratory endurance. The standardized scores of the nine variables in the model were used to develop a fitness index for adults with intellectual disabilities. Simultaneous multigroup analyses were also conducted in order to test the stability of the proposed model across gender and across active and sedentary participants.

The findings demonstrated that the proposed structure was well supported (comparative fit index = 0.97, standardized root mean square error of approximation = 0.05) and stable across subgroups.

A model with four underlying factors has been shown to have acceptable validity to represent the fitness of adults with intellectual disabilities.