Health literacy has been defined as the degree to which individuals have the capacity to obtain, process, and understand the basic health information and services needed to make appropriate health decisions [1
].Over the last decade, health literacy has become a hot spot of research[3
]. With a deeper understanding of health literacy in academic circles, more and more researchers find that a lack of health literacy can cause some adverse effects for individuals and society. Low literacy is associated with a variety of adverse health outcomes, including increased mortality, hospitalization, and in some cases poorer control of chronic health conditions [5
]. Additionally, limited health literacy impacts on the prevention and screening of diseases, health behavior, the taking of patients’ history and the interpretation of diagnoses [10
]. Knowing little about preventive care, people with low health literacy tend to use more medicines and more expensive healthcare services, including hospitalization and emergency services [7
Some investigators have elucidated explained the relationship of between limited health literacy and socioeconomic indicators, health behaviors, and health outcomes [17
]. Researchers have focused on explaining the potential mechanisms between these variables. Aging, the language barrier, low education, bad socio-economic status and suffering from chronic diseases were all regarded as risk factors of limited health literacy [6
Though limited health literacy has been shown to be associated with worse health outcomes and some socioeconomic characteristics, the causal pathways are not entirely known. Several researches have focused on explaining potential mechanisms. The conceptual model by Baker illustrates these hypothesized relationships by highlighting individual capacities that are associated with literacy skill, the complexity of both printed and spoken health information and other factors such as cultural norms that are relevant to health outcomes [20
In 2007, Paasche-Orlow and Wolf proposed a conceptual causal model to explain associations between limited health literacy and health outcomes [21
]. In their model, socioeconomic indicators are the basic factors influencing health literacy. These include level of education reached, ethnicity, age, occupation and income. Their model distinguishes three different types of health action that mediate the impact of health literacy on health: access to and utilization of health care, patient-provider interaction, and self-care. Each of these domains is defined not only by patient factors but also by external factors that can be attributed to the health care provider or the health system. The pathways are particularly useful in highlighting the role of health actions and providing a useful taxonomy of behavioral domains.
von Wagner’s review introduced a framework drawing on ideas from health psychology and proposing that associations between health literacy and health outcomes could be mediated by a range of health actions involving access to and use of health care, patient–provider interactions, and the management of health and illness[22
]. The framework outlines ways in which health literacy might affect either health actions themselves or their motivational and volitional determinants, which have been identified in social cognition models.
McCormack established a conceptual framework for individual health literacy[23
]. The framework illustrates how health literacy functions at the level of the individual, while acknowledging that factors external to the individual (including family, setting, community, culture and media) influence all the relationships represented in the model. The framework is organized into four primary elements: (1) health-related stimulus; (2) factors that influence the development and use of health literacy skills, including socio-demographic characteristics, resources , prior knowledge and capabilities; (3) health literacy skills needed to comprehend the stimulus and perform the task; and (4) mediators between health literacy and health outcomes including motivation, attitudes, emotions, and self-efficacy. The health related outcomes include behaviors and status.
Although all these models or frameworks have given the relationship between socio-demographic characteristics, prior knowledge, health literacy, health behavior/action and health outcomes, they are all theoretical explanations. Few studies have tried to validate them through the use of statistical modeling. So this study aimed to develop a health literacy model and to statistically validate it using path analysis.
Hypothesis – a health literacy model
With the models of Baker, Paasche-Orlow, von Wagner and McCormack for reference, we proposed a health literacy model at an individual level. Figure
represents this model. In this model, socio-demographic indicators, including age, gender, level of education reached, occupation and income, are the basic factors influencing other variables. Besides socio-demographic indicators, prior knowledge also influences the development of health literacy skills. Then health literacy has direct effect on health behavior, meanwhile, as a mediator between prior knowledge and health behavior. Finally, health behavior influences health status.
Hypothesis of a health literacy model at an individual level.