Women's health literacy and attendance in breast cancer screening: a Danish population-based study combining survey and register data

Aim: To investigate the association between women's health literacy and attendance in the Danish national breast cancer screening programme. Methods: In a population-based cross-sectional study, information on two health literacy subscales, measured using the Health Literacy Questionnaire (HLQ), and sociodemographic factors was obtained from the 'How are you? 2017' survey in the Central Denmark Region. Information on screening attendance was obtained from register data from 2016-2017. Data were linked based on individual civil registration numbers. To account for missing data, multiple imputation by chained equations was implemented to fill in missing values on all variables. Unadjusted and adjusted logistic regression analyses were performed separately for two HLQ subscales to estimate odds ratio (OR) of screening attendance. Both multiple imputation analyses and complete case analyses were performed. Results: A total of 6012 women were included in multiple imputed statistical analyses. Generally, women had high health literacy levels. In multiple imputed analyses, the unadjusted OR of the primary HLQ subscale, understanding, was 1.32 (95% confidence interval (CI): 1.10-1.59), indicating higher odds for screening attendance with higher health literacy level. However, after adjustment no significant association between the HLQ subscale of understanding and screening attendance was found (OR 1.09 (95% CI: 0.90-1.33)). Similar results were found for the secondary HLQ subscale of engaging (insignificant association in adjusted analysis). No effect modification from sociodemographic characteristics was found. Similar results were found in complete case analyses. Conclusions: No significant association was found between health literacy and attendance in the Danish breast cancer screening programme.