Health Literacy: A Brief Overview

Introduction

The Institute of Medicine (IOM) defines health literacy as "the degree to which an individual can obtain, process, and understand basic health information and services they need to make appropriate health decisions" (p. 1, Institute of Medicine, 2004). According to the IOM, health literacy to some degree requires medical knowledge, navigational skills, cultural competency, and initiative. Similarly, the American Medical Association (1999) defines health literacy as the ability to read and comprehend prescription bottles, appointment slips, and other essential health-related materials. Health literacy is more than a measure of reading ability; health literacy also consists of writing, listening, speaking, and math ability as well as conceptual knowledge (Dewalt & Pignone, 2005; Rao, 2007). Further, basic health literacy skills are necessary to obtain, process, and understand basic health information. In summary, health literacy is much more than the ability to read pamphlets and flyers received from health-care professionals. It is the ability to access and use health information effectively to empower oneself (Gazmararian, Curran, Parker, Bernhardt, & DeBuono, 2005) while using such knowledge to independently make choices that preserve, improve, and manage one's health (Abel, 2007).

Functional health literacy skills are believed to be lacking in 90 million Americans or as many as 50% of U.S. adults (U.S. Department of Health and Human Services, 2000). According to the 2003 National Assessment of Adult Literacy (NAAL), which is the nation's most comprehensive measure of adult literacy and includes a health literacy component, approximately 12% of the U.S. adult population (i.e., age 16 and older) are lacking in health literacy. The NAAL report concluded that more than a third of U.S. adults or approximately 77 million Americans have difficulty with common daily tasks, such as following the directions on a medicine label, or following and adhering to a immunization schedule (U.S. Department of Health and Human Services, 2003). In addition to the NAAL report, other studies have highlighted issues associated with low health literacy in the U.S. In a study of two public U.S. hospitals, Williams et al. (1995) found that 60% of patients did not understand a standard informed consent form, 42% of patients did not understand directions for taking medication on an empty stomach; and 26% did not understand the information on an appointment slip. Such individuals would likely have difficulty with self-care instructions and understanding health education brochures, which are both critical to post-discharge health outcomes.

The likelihood of low health literacy varies significantly across populations and sociodemographic groups. Populations that are most prone to health illiteracy include those from low socioeconomic status, the elderly, the homeless, and racial/ethnic minorities (Institute of Medicine, 2004). The IOM reported that approximately 28% of White adults exhibited basic or below basic health literacy skills while the percentage of Latino adults with such skills was 65%. Low or inadequate health literacy is also frequently associated with lower levels of education and among individuals from lower socioeconomic groups (Dewalt & Pignone, 2005; U.S. Department of Health and Human Services, 2008). In addition, low health literacy is also greater among adults age 65 and older with the percentage of individuals exhibiting skills below a basic level increasing with age (U.S. Department of Health and Human Services, 2003). Studies indicate that the likelihood of a person being health illiterate increases with age and that 80 percent of people over the age of 60 have difficulty filling out common health-related forms (Rao, 2007; Safeer & Keenan, 2005). This issue is of major concern because elderly populations experience a greater burden of chronic diseases and require the greatest demand for functional reading ability (Baker et al., 2002). Finally, uninsured adults, adults with Medicaid, and adults without at least a high school education tend to exhibit lower health literacy skills than adults with private insurance and those adults with at least a high school education (U.S. Department of Health and Human Services, 2008).

Other populations are also at a higher risk for low health literacy, including individuals with lower levels of education, adults who are not primary English speakers, and acutely sick patients. In a study performed in the emergency department of a hospital in North Carolina, the Test of Functional Health Literacy in Adults (TOFHLA; Parker, Baker, Williams, & Nurss, 1995) was given to both English-only and Spanish-only speaking adults. Brice et al. (2008) found the mean TOFHLA score for English-speaking subjects to be 90.78 and the scores for Spanish-speaking subjects to be 59.72, indicating that English-speaking patients in the emergency department had significantly higher health literacy. Similarly, in a survey of 1200 Californians conducted in 11 different languages, Wilson and colleagues (2005) found that limited English proficiency was associated with barriers to comprehension during medical encounters and resulted in an increased risk of adverse medication encounters (Wilson, Chen, Grumbach, Wang, & Fernandez, 2005).

The presence of limited-English proficiency in addition to low health literacy has also been linked to other health-related issues. For example, a recent study of racial/ethnic minority non-English speakers noted that lower health literacy can present an additional burden resulting in unique stressors that contributed to mental health issues (Coffman & Norton, 2010). Similarly, studies have also shown that populations with speech, language, and cognitive disorders and those with hearing and vision impairments may also be more at risk for low health literacy (Safeer & Keenan, 2005). While there are certain populations that seem to be more prone to problems with health literacy, even highly educated individuals can have difficulty understanding and following medical information (Hasselkus, 2009b). The U.S. Department of Health and Human Services, Office of Disease Prevention and Health Promotion (2008) notes that even adults with strong health literacy skills may face difficulties when: (1) they are not familiar with medical terms or how their bodies work; (2) they have to interpret numbers or risks to make health decisions; (3) they are diagnosed with a serious illness or they are scared or confused; or (4) they experience complex conditions that require complicated self-care.