Abstract Background Health-related control and self-efficacy beliefs can be assessed in the general population using Multidimensional Health Locus of Control-A subscales (MHLC-A) and the General Self-Efficacy Scale (GSES), respectively. Objective To test construct validity, internal consistency, reliability (test-retest) and ceiling and floor effects of Portuguese-Brazil versions of MHLC-A and GSES. Method Civil servants (N=2901) enrolled in a large Brazilian cohort were included. A new version of the GSES was produced (GSES-Brazil). Procedures for cross-cultural adaptation and testing of psychometric properties followed well-accepted international guidelines.

Results Confirmatory factor analyses yielded the following indices:

MHLC-A (tridimensional model): χ2[df]=223.45[132], p-value <0.01; CFI=0.87; TLI=0.85; RMSEA=0.07 (0.07-0.08); WRMR=3.00. GSES-Brazil (unidimensional model): χ2[df]=788.60[35], p-value <0.01; CFI=0.95; TLI=0.94; RMSEA=0.09 (0.08-0.09); WRMR=2.50. Cronbach’s alpha coefficients and Intraclass Correlation Coefficients (ICC2,1) ranged from 0.57 (0.54-0.59) and 0.57 (0.47-0.65) for MHLC-A internality to 0.80 (0.79-0.81) and 0.71 (0.66-0.77) for GSES-Brazil, respectively. There was no evidence of ceiling and floor effects. Convergent validity analyses provided further support for construct validity of both scales. Conclusion These findings support the use of the newly developed version of GSES-Brazil for the assessment of general self-efficacy of adult Brazilians. Internal consistency was lower than ideal for MHLC-A, indicating these subscales may need further refinements to provide a more psychometrically sound measure of control beliefs.