The Brazilian validation of a health literacy instrument: the newest vital sign

Abstract

Objective: This study aimed to perform the cross-cultural adaptation and validation of the NVS for Brazilian Portuguese.

Material and Methods: Two hundred and fifty adults responded to the adapted version of the NVS, the Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30), ten questions of the National Functional Literacy Index (NFLI), and a questionnaire about demographic and oral health-related aspects. Statistical analysis determined the internal consistency, stability, difficulty of items, and convergent/discriminant/predictive validities of the NVS. p < .05 was considered significant.

Results: The NVS displayed a good internal consistency (Cronbach’s alpha = 0.79) and a fair stability (ICC = 0.57; 0.39–0.70 95% CI). Seventy-two percent of participants answered the easier question (#5) correctly, whereas only 28.4% were successful in responding the most difficult question (#1). The convergent validity of the NVS was demonstrated by its significant correlation with the BREALD-30 (Rs = 0.601, p < .001) and NFLI (Rs = 0.544, p < .001). The observation of higher NVS scores among health professionals, white and more educated people confirmed the discriminant validity of the instrument. Moreover, health literacy was a significant predictor of self-reported oral health and reason for dental utilization.

Conclusion: The NVS demonstrated adequate psychometric properties to be applied in Brazilian oral health epidemiological surveys.

Keywords:

• Health literacy
• oral health
• surveys and questionnaires

Acknowledgments

The authors thank Juliana Godoy Oliveira for her support during the interviews of participants.

Disclosure statement

The authors report no conflicts of interest.

Additional information

Funding

This research was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).