Relationship between health literacy and quality of life among cancer survivors in China: a cross-sectional study

Objective To evaluate the association between health literacy (HL) and quality of life (QOL) among cancer survivors in China. Design Cross-sectional study in China. Setting and participants This is a cross-sectional observational study of 4589 cancer survivors aged 18 years and older from the Shanghai Cancer Rehabilitation Club. Participants were enrolled and completed the questionnaires between May and July 2017. Measurement HL was assessed by three established screening questions and QOL was evaluated using the simplified Chinese version of the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire-Core 30 items. Answers to all questionnaires were collected through face-to-face interviews or through self-administered questionnaires for literate participants. Participants were excluded if they did not answer any one of the HL questions. Baseline characteristics were compared by levels of HL using chi(2) test for categorical variables and Wilcoxon rank-sum test for non-normal continuous variables. The item response theory (IRT) was used to evaluate the existing measure of HL. Linear regression and logistic regression models were used to investigate the association between HL and QOL. SAS V.9.4 and MULTILOG V.7.03 were used in the analysis. Results There were 4589 participants included in the study. The calculated results of IRT scale parameters of HL entries indicate that the entries have better discrimination and difficulty. Of the 4589 respondents, 159 (3.5%) had low HL. After adjusting for sociodemographic characteristics, treatment regimen and years with cancers, for each one-point decrement in HL score the QOL score increased by 2.07 (p<0.001). Cancer survivors with low HL were less likely than those with adequate HL to achieve better QOL. In logistic regression, low HL was independently associated with poor QOL (adjusted OR, 2.81; 95% CI 1.94 to 4.06; p<0.001). Conclusions Low HL was independently associated with poor QOL among cancer survivors of the Shanghai Cancer Rehabilitation Club.