The association between quality of life(QOL) and health literacy among junior middle school students: a cross-sectional study

Despite the lack of uniform standard for the definition of QOL, there is a shared understanding to regard the concept of QOL as “the individual’s perception of their position in life in the context of the culture and value systems in which they live, and in relation to their goals, expectations, standards, and concerns” [1]. The level and determinants of QOL in adults have been well investigated in developed countries such as the US [2], the UK [3], Netherlands [4], and Sweden [5]. However, few studies have been reported on QOL in developing countries, especially for children and adolescents. Junior school stage is a necessary period of transition from childhood to maturity, which is critical for individual physical, psychological and social adaptation. During this period, the physical and psychological health and QOL may affect their life, so it is of far-reaching significance to study the QOL of junior school students. Since the 1950s, studies on QOL have been carried out in the United States, Canada, Western Europe, Eastern Europe and some Asian countries, while studies on QOL in China started late in the mid-1980s, and research on QOL in children and adolescents starts even later [6]. Xiao Cailan et al.’s research on primary and middle school students in Hebei province China found that students with a QOL above the middle level accounted for 67%, and there was still much room for improvement in the QOL of middle school students [6]. This result is lower than Wang’ research on children and adolescents in Chongqing, which found nearly 80% of students with a QOL above the middle level [7]. In short, existing researches have shown the QOL of children and adolescents at home and abroad is not high. In addition, those researches that do exist managing QOL among children and adolescents mainly focused on various pediatric diseases [8–12]. Researches on QOL amongst community populations of children and adolescents are needed. In our previous cross-sectional study of QOL among junior middle school students, we found that QOL may be influenced by demographic factors (e.g. sex, parent education level, family structure, parenting), the presence of chronic disease and poor vision [13]. Additionally, QOL may be in the position of affecting students’ daily performance, activities, and communication.

Health literacy, “degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions” [14], has become an important health policy and health promotion agenda item in recent years. Unlike fixed social structures and demographic characteristics, which cannot be altered without massive social changing and political action, health literacy is susceptible to social environments and can be improved by targeted health education [15]. Although epidemiological estimate on the level of health literacy varies depending upon the characteristics of the sample, the measurement methods, standardized assessment means, and heterogeneity in the source of information, studies indicate that the health literacy of Chinese children and adolescents was generally low [16–20]. Data from a nationwide survey on health literacy showed merely 25.2% of adolescents aged 15–24 years with adequate health literacy skills, 15.9% with adequate knowledge, and 6.4% with adequate behaviors [21]. In another study in Guangdong, Xiao-Hua Ye et al. found the prevalence of adequate health literacy among in-school adolescents was only 14.4% [22], which was much lower than the 52% found in high school students in Texas US [23] and 41% found in Taiwan area [24]. A rigorous body of work in the previous day have established a clear link between inadequate health literacy and a wide variety of negative health outcomes in adults, including increased hospitalizations [25], greater use of emergency care [26] and poorer health status [27]. Fewer studies, however, are available in children and adolescents, and those that do exist demonstrate an association between lower parent or caregiver health literacy and more dosing errors in pediatric medication [28], worse child asthma and diabetes care [29, 30], lower child health insurance coverage [31], and higher pediatric emergency department use and outpatient visits [32]. Indeed, the decisions of parents or caregivers do impact children’s health status, however, children can also be in a position to decide their own health.

Evidence [33–35] continues to grow linking limited health literacy to poor QOL among patients in the medical/clinical context, however, whether health literacy significantly influences QOL among general populations of students has been seldom reported. To address this need, we explored the relationship between QOL and different levels of health literacy among junior middle school students, while controlling for other covariates (e.g. sex, grade, place of residence, economic status, parent education attainment, and so on).

The impacts of health literacy on health status and health outcomes have been widely discussed in the previous literature [27, 28]. Nevertheless, to our knowledge, this is the first study to examine the relationship between health literacy and QOL in general populations of junior middle school students. In concordance with our hypothesis, health literacy emerged as a moderator for the QOL in junior middle school students. Results indicated that students with low health literacy had a higher risk to get fewer scores of QOL, even adjusting for social-demographics. Furthermore, the associations between health literacy levels and QOL of overall and each subscale were more pronounced in the low health literacy group than in the medium health literacy group.

After categorizing the health literacy into 3 levels by using quartiles as the cut-off points, we found that about one-quarter of students presented low health literacy,which is higher than other studies reported with samples from different age groups and using different previously validated evaluation instruments, such as Chang and her colleagues’ study [43] measured by the Chinese version of Test of Functional Health Literacy (TOFHL)for adolescents among Taiwanese students, and the results reported by Chisolm et al. [44] assessed with the Rapid Estimate of Adult Literacy in Medicine, teen version (REALM-Teen). Due to the lack of studies specifically conducted among teenagers, together with the scale we used in this present study differs from the other’s, little information can be compared on the overall health literacy level of teenagers in different regions, not to mention any regional comparisons.

Moreover, we found that students with low health literacy were more likely to get fewer scores of QOL comparing to their counterparts with high HL, even adjusting for covariates. This finding amongst junior middle school students is concordance with reported findings among adults and patients [35, 45, 46]. For instance; a study among patients with ischemic heart disease showed that increasing health literacy may improve health-related QOL and reduce the impact of ischemic heart disease [35]. In another study, Cuili Wang and her colleagues found that low health literacy was associated with poorer health-related QOL in the context of chronic disease [45]. However, owing to the lack of study addressing the relationship between health literacy and perception of QOL by the general adolescent public, comparisons of results in this age group would be difficult. There are several reasons may explain why junior middle school students with high health literacy levels have a higher QOL than those with low health literacy levels. Firstly, students with higher health literacy levels may be more prone to expose to the health-related information, which provided by medical professionals, parents, teachers and friends. Once equipped with a solid understanding of their health, these students are more likely to make better decisions to improve their QOL. Instead, poor health literacy may limit students’ ability to communicate with health providers, understand and follow health providers’ instructions, thus, leaving them without the appropriate knowledge to make informed decisions [47]. Secondly, since numerous studies [29–32] have demonstrated the impact of parent/caregiver’s health literacy on the health status or outcomes of their children, together with children’s health literacy are significantly associated with their parent/caregiver’s health literacy [48], there is every reason to believe children can also be in a position to decide their own health and QOL. Lastly, students with low health literacy are more likely to engage in risky behaviors such as smoking, alcohol consumption, insufficient physical activity, unhealthy dietary intakes. All these behaviors have been identified significantly associating with poor QOL [44]. As for the specific domains of QOL, our results corroborate the Ownby RL study [49] which found that those with low health literacy experience poor QOL and suffer from more mental and physical health problems. In addition, our findings showed that low health literacy was associated with low pubertal well-being.This can be partly explained as junior middle school students are right in their physical and psychological development stage, they are prone to come up with physical or psychological problems.

The association between low health literacy and QOL could be recognized in a wider context of the influencing factors of health literacy. Data analysis showed that, students living in urban areas were more likely to have higher health literacy than their urban counterparts, consistent with our expected and other studies in China [50], which may be related with the degree of economic development, the disequilibrium of health-related resources and the accessibility of health information [50, 51]. Regarding to the discrepancy of sex, most of the studies [46, 52] point to better health literacy for females, that corroborates our findings. There were several possible explanations for this divergence. For one thing, female students were more concerned about health information and were more willing to turn to families, friends, teachers and mass media for health-related information [53]. For another, female students may pay more attention to personal image and health-related details than males. Additionally, we found that students who attained a low health literacy level were more likely to come from a low familial resource environment, such as low income, low parental educational levels, and poor family relationship. It would be inherent to associate a low familial resource environment with low household economic status, lower parental educational levels, higher proportion of manual labour employment, high prevalence of parental unhealthy behaviors, and poorer dietary pattern. All these factors involved have been identified as the risky factors for low QOL. Similar results were found in earlier studies [54–56].

This study suggested that the inadequate health literacy may contribute to poorer QOL among junior middle school students. Improving health literacy among students may have a positive effect on their QOL. Therefore, the study highlights the importance of strengthening efforts to increase the level of health literacy across adolescents and teenagers, especially among those from a low familial resource environment and those living in rural areas. Overall, to improve students’ QOL, public health efforts for further improving awareness and enhancing effective promotion and education are urgently needed in junior middle school students, especially in low health literacy populations. Additionally, it merits further longitudinal studies to confirm the impact of health literacy on QOL, and verify the hypothesis that improving students health literacy may be effective in modifying QOL.