Validación del índice de satisfacción con la vida en la tercera edad.

Objectives: Study the factor structure of Life Satisfaction Index for the third age, short form (LSITA-SF), its internal consistency, content validity, and to contrast its divergent validity. This index is proposed as a subjective indicator of successful aging Roy Adaptation Model, self concept mode. It is contrasted to a brief measurement of depression (CESD-7) that served as contextual stimuli in a major study. Materials and methods: The LSITA-SF scale and the (CESD-7) were applied to a non-probabilistic sample of 255 mexican volunteers from 60 to 100 years old. The content validity was evaluated by three experts. The internal consistency was calculated by the Cronbach's Alpha coefficient, the factor analysis by Principal Component Analysis and Varimax rotation, the confirmatory factor analysis by Maximum Likelihood and the divergent validity by the Spearman correlation coefficient. Results: The content validity was adequate. A three correlated factors model showed the best fit (X² [41, N = 255] = 77.30, p = 0,001, GFI = 0,96, AGFI = 0,935, and RMSEA = 0,059), one item was deleted. Internal consistency was (a = 0,80). The correlation between LSITA-SF11 and CESD-7 was moderate (rs = -0,38); and between LSITA-11 and physical health measured by five items of SF-12 was (rs = 0,32). Conclusion: The 11-items LSITA scale shows preliminary good properties of reliability and validity in Mexican elderly people. We suggest its study for further validation in Mexico and other Spanish speaking countries. [ABSTRACT FROM AUTHOR]