Psychometric properties and factor structure of the Medical Outcomes Study Social Support Survey Instrument in a sample of Spanish older adults.

The aim of this study was to explore the factor structure of the MOS-SSS in a sample of community-dwelling Spanish older adults. The sample comprised 406 community-dwelling older adults aged between 65 to 99 years old (M age = 74.88, SD = 6.75). Confirmatory factor analysis (CFA) was performed, and four possible models were compared: the one-factor, the three-factor, the four-factor and the five-factor model, using an additional analysis with a second-order factor. The internal consistency reliability and convergent validity of the scale were also assessed. For the 19-item MOS-SSS scale, the five-factor model had the best fit to the data. All five subscales of the MOS-SSS showed adequate internal consistency, good convergent and discriminant validity. These findings contribute to the literature on the factor structure of the MOS-SSS in Spanish older adults. The MOS-SSS is a reliable and valid scale that can be used to assess Spanish older adults' social support perception for social services, health and in research contexts.