Psychometrics and measurement invariance: Health Literacy Scale for Vietnamese and Indonesian married immigrants

Abstract

Aims: To examine the psychometrics and measurement invariance of the Short-Form Health Literacy 12-item questionnaire (HL-SF12) among Vietnamese and Indonesian married immigrants.

Design: A cross-sectional survey design.

Methods: In total, 1171 Vietnamese and Indonesian married immigrants were enrolled between September 2019 and December 2019. An exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to verify the structural validity of the suggested factor structure. The multiple-group CFA (MGCFA) used a series of hierarchical nested-in models as a measurement invariance test which confirmed the adequacy of the model fit at each stage.

Results/findings: The Kaiser-Meyer-Olkin coefficient was 0.898, and the Bartlett test of sphericity was statistically significant (χ² [66] = 1965.97, p < 0.01). According to a scree plot and Kaiser's criterion for eigenvalues of >1, the EFA explained 61.6% of the total variance and confirmed three theoretically supported factors of health care, disease prevention and health promotion. The 12 items showed factor loadings of >0.4 and four items were in each subscale. The CFA showed adequate structural validity, including a relative chi-squared/degrees of freedom (X² /df) of 2.01, a comparative fit index (CFI) of 0.98 and a root mean square error of approximation (RMSEA) of 0.04 (95% confidence interval [0.03, 0.05]) in married immigrants. For the measurement invariance, a change in the goodness-of-fit measures did not exceed 0.02 for the RMSEA or 0.01 for the CFI. The results indicated Cronbach's α values of 0.87 for the HL-SF12 scale in Vietnamese and Indonesian combined samples (n = 1171). A t-test showed that the HL-SF12 and its three subscales were unable to significantly differentiate between Vietnamese and Indonesian groups (all p > 0.05).

Conclusions: The HL-SF12 scale showed acceptable theoretically supported structural validity, equivalent measurement invariance and reliable internal consistency among Vietnamese and Indonesian married immigrants. Measurements of immigrants' HL using the HL-SF12 could be integrated into future immigrant health policies.

Impact: As the first study of the measurement invariance of the HL-SF12 instrument among immigrants. Related factors of immigrants' HL can be further explored to increase immigrants' health and empowerment.

Keywords: emigration and immigration; factor analysis; health literacy; health service; immigrants; nurse; nursing; reliability of result; validity and reliability; validity of results.