Health Literacy Resources: Understanding Medical Information
Health literacy describes the degree to which individuals can obtain, process, and understand basic health information and services needed to make appropriate health decisions. Federal agencies including the U.S. Department of Health and Human Services (HHS) and the Agency for Healthcare Research and Quality (AHRQ) have established health literacy as a measurable public health priority with direct links to patient safety, treatment adherence, and health disparities. This page covers the definition, mechanism, common scenarios, and decision boundaries relevant to health literacy in the U.S. healthcare context, with citations to named federal and standards sources.
Definition and scope
The National Academy of Medicine (NAM), formerly the Institute of Medicine, defines health literacy in its 2004 report Health Literacy: A Prescription to End Confusion as "the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions." HHS extended this definition in Healthy People 2030 to incorporate a systemic dimension — organizations bear responsibility for providing health information in formats people can actually use.
Health literacy operates across two distinct domains:
- Personal health literacy: The individual's capacity to find, understand, evaluate, and use health information for decisions about themselves or others.
- Organizational health literacy: The degree to which an organization equitably enables individuals to find, understand, and use information and services to inform health-related decisions (HHS Office of Disease Prevention and Health Promotion, Healthy People 2030).
Scope boundaries matter: health literacy is distinct from general literacy, education level, or intelligence. A person with a graduate degree may have low health literacy in the context of an unfamiliar diagnosis. The AHRQ Health Literacy Universal Precautions Toolkit recommends treating all patients as potentially at risk for health literacy challenges, regardless of apparent education or socioeconomic status.
Understanding health literacy intersects directly with patient rights and responsibilities and underpins the informed consent process, addressed separately in the informed consent patient guide.
How it works
Health literacy functions as a three-phase interaction between the patient, the information environment, and the delivery system.
Phase 1 — Access: Individuals locate health information through clinical encounters, written materials, digital platforms, or community resources. The readability of materials is measured against standard benchmarks; the American Medical Association (AMA) Foundation recommends that written patient education materials be written at or below a 6th-grade reading level, though studies cited by AHRQ have found that the average patient-facing material is written at a 10th-grade level or higher.
Phase 2 — Processing: Patients interpret numerical information (dosage, risk percentages, lab reference ranges), evaluate source credibility, and reconcile conflicting information. Numeracy — the ability to work with quantitative health data — is a discrete skill within health literacy. The National Assessment of Adult Literacy (NAAL), administered by the National Center for Education Statistics (NCES), found that only 12 percent of U.S. adults scored at the "proficient" health literacy level, with 36 percent at the "basic" level and 14 percent at the "below basic" level (NCES, 2006 NAAL results).
Phase 3 — Application: Individuals apply understood information to decisions — filling prescriptions correctly, adhering to follow-up schedules, navigating insurance coverage, or completing forms accurately. Breakdown at this phase produces measurable patient safety events. AHRQ classifies inadequate health literacy as a root cause factor in medication errors, missed diagnoses, and preventable hospitalizations.
Structured tools used by clinicians to assess and support health literacy include:
- REALM (Rapid Estimate of Adult Literacy in Medicine) — a validated 66-word reading test measuring medical vocabulary recognition.
- TOHFLA (Test of Functional Health Literacy in Adults) — assesses reading comprehension and numeracy using actual clinical materials.
- Newest Vital Sign (NVS) — a 6-question instrument using a nutrition label; a score of 0–1 indicates high likelihood of limited literacy.
- Ask Me 3 — a patient-facing communication tool developed by the Institute for Healthcare Improvement (IHI) prompting patients to ask: What is my main problem? What do I need to do? Why is it important?
Common scenarios
Health literacy gaps surface across predictable clinical and administrative contexts. Recognizing these scenarios is the first step toward applying appropriate resources.
Medication instructions: Patients with limited health literacy are 1.5 to 2 times more likely to misuse medications due to label misinterpretation, according to a literature synthesis published in the Journal of General Internal Medicine and summarized by AHRQ. Dosing frequency, drug interactions, and storage requirements represent the highest-error subsets.
Insurance and billing navigation: Explanation of benefits (EOB) documents, prior authorization requirements, and formulary tiers require functional literacy and numeracy that exceed the capabilities of a substantial portion of enrollees. This directly connects to challenges documented in the health insurance appeals process and medical billing advocacy contexts.
Chronic disease self-management: Conditions such as Type 2 diabetes, heart failure, and asthma require patients to interpret glucose readings, fluid weight logs, and peak flow measurements. The Centers for Disease Control and Prevention (CDC) identifies chronic disease management as a primary domain where health literacy failures produce preventable acute events.
Language access: Health literacy and language access overlap but are legally distinct. Title VI of the Civil Rights Act of 1964 requires federally funded healthcare entities to provide meaningful access for individuals with limited English proficiency (LEP). Language access rights in healthcare represent a separate, parallel framework covered in the language access rights in healthcare reference.
Informed consent: Consent documents frequently exceed the reading comprehension level of patients who are asked to sign them. The Joint Commission identifies consent form readability as a patient safety indicator under its health equity and patient safety frameworks.
Self-advocacy skills are foundational across all these scenarios — a topic developed further in the self-advocacy skills for patients reference.
Decision boundaries
Health literacy resources differ in purpose, target audience, and appropriate application context. The following classification structure maps resource types to function.
Type A — Screening and assessment tools (clinical use): REALM, TOHFLA, NVS. Purpose: identify individual literacy level to tailor clinical communication. These are clinician-administered instruments, not self-assessment tools. Validated psychometric properties make them appropriate for research and quality improvement programs.
Type B — Plain-language communication standards (organizational use): The Federal Plain Language Guidelines establish federal standards for government health communications. The Plain Writing Act of 2010 (Public Law 111-274) mandates that federal agencies use plain language in documents directed at the public, which includes HHS patient education materials.
Type C — Patient-facing education resources (direct use): Resources produced by the MedlinePlus platform (National Library of Medicine), the CDC Plain Language materials, and the NIH National Cancer Institute patient education publications are designed at accessible reading levels and reviewed for accuracy.
Type D — Systemic and policy frameworks (organizational accountability): The National CLAS Standards (Culturally and Linguistically Appropriate Services), issued by the HHS Office of Minority Health, establish 15 action-oriented standards for organizations to advance health equity. Standard 5 specifically addresses communication and language assistance. The CLAS Standards distinguish between preferred language (personal health literacy support) and required language access (civil rights compliance) — a boundary that determines which organizational obligations are mandatory versus aspirational.
The decision point between resource types depends on the actor (clinician, patient, or organization), the purpose (assessment, communication, or systemic change), and the regulatory context. For example, CLAS Standard 5 language assistance is a mandatory requirement for federally funded entities, while adoption of the Ask Me 3 framework is voluntary best practice. Organizational health literacy programs may also connect to broader care coordination and case management structures that address literacy barriers within care transitions.
References
- U.S. Department of Health and Human Services — Healthy People 2030: Health Literacy
- Agency for Healthcare Research and Quality (AHRQ) — Health Literacy
- [AHRQ Health Literacy Universal Precautions Toolkit](https://www.ahrq.gov/health-literacy/improve/precautions/index