Cross-cultural adaptation and validation of the health literacy assessment tool METER in the Portuguese adult population

Objective

We aimed to culturally adapt and validate METER in the Portuguese population, and to define cut-off values for adequate health literacy.

Methods

We used the standard procedure for the adaptation of the words and surveyed health professionals to select the non-words. The instrument was administered to a total sample of 249 participants and retested in a sub-sample of 45 after three months. Cut-offs were defined using the modified Angoff procedure. Construct validity was assessed through association with educational attainment and health-related occupation.

Results

Exploratory factor analysis revealed two dimensions of the instrument, one for words and another for non-words. METER showed a high degree of internal consistency, and acceptable test–retest reliability. Adequate health literacy was defined as scoring at least 35/40 in words and 18/30 in non-words. Physicians scored higher than any other group, followed by health researchers, researchers from other areas and by people with progressively lower levels of education (p < 0.001).

Conclusion

We culturally adapted a brief and simple instrument for health literacy assessment, and showed it was valid and reliable.

Practice implications

The Portuguese version of METER can be used to assess health literacy in Portuguese adults and to explore associations with health outcomes.