Methods and challenges for assessing health literacy in Brazilian cities: population survey

To present the response rates and strategies to reduce the number of challenges from multi-center research on Health Literacy carried out in five Brazilian cities.

Adults living in urban areas of cities in the states of Rio Grande do Sul (Porto Alegre, Santa Maria and Pelotas) and Mato Grosso do Sul (Campo Grande and Dourados) were interviewed between October 2023 and March 2024. Cluster sampling was carried out in three stages (census sector, block and household). Health literacy was assessed using the Brazilian version of the European Health Literacy Survey Questionnaire Short Form, and the Teste de Letramento em Saúde. The response rate for each city was obtained by dividing the number of interviews conducted by the number of households selected, and post-stratification weights were applied according to age, sex and education.

From 150 census sectors initially drawn, 1,181 individuals from 136 census sectors were interviewed. The participating cities' household response rate varied from 33.04% to 58.09%. Different strategies were employed to reduce low response rates due to absent residents and number of refusals, identified as main challenges in data collection. Quality control was performed continuously, with direct supervision of interviewers, daily data analysis and telephone re-interviews.

Low response rates in face-to-face interviews, mainly due to absent residents and refusals, as well as in telephone re-interviews, suggest that strategies need to be expanded to address these challenges in household surveys.