Background and Objectives for the Systematic Review

Background

Health literacy, as defined by the Institute of Medicine (IOM) in 2004, is “the degree to which individuals can obtain, process, and understand the basic health information and services they need to make appropriate health decisions.” This capacity includes the ability to interpret documents, read and write prose (print literacy), use quantitative information (numeracy), and speak and listen effectively (oral literacy) in a health care setting.

In 2003, the US Department of Education conducted a survey entitled “National Assessment of Adult Literacy” (NAAL). The most comprehensive examination of adult literacy to date, the NAAL surveyed more than 19,000 adults aged 16 and older. The assessment included items intended to directly measure health literacy. More than one-third of respondents (36%) scored in the lowest two categories (“basic” and “below basic”), suggesting that approximately 80 million adults in the United States have limited health literacy (Kutner et al., 2006). These people may have difficulty with even simple tasks like reading and understanding the instructions on a prescription bottle or filling out an insurance form. Low health literacy skills are more common in certain subgroups, including minorities, the elderly, Medicaid recipients, and people who have not completed high school.

In the past decade, researchers have demonstrated that low health literacy can have far-reaching consequences for an individual’s health. In our 2003 systematic evidence review, limited health literacy was associated with less knowledge of health care services and outcomes and adverse outcomes including increased disease prevalence and severity, lower utilization of screening and preventive services, and higher hospitalization rates (Berkman et al., 2004; DeWalt el al., 2004). More recently, low health literacy has been linked to higher mortality in older adults (Sudore et al., 2006). In our prior review, we also found some evidence that interventions may reduce the adverse effects associated with low health literacy.

Given the clear association between low health literacy and poor health outcomes, and the potential to reduce these outcomes with novel interventions, several national organizations have promoted health literacy as a research priority. With such attention from the American Medical Association (AMA), the IOM, National Institutes of Health (NIH), and Healthy People 2010, the research community has responded with new work in this field.

To synthesize the increasing volume of literature on health literacy, the Agency for Healthcare Research and Quality (AHRQ) has commissioned the RTI International–University of North Carolina Evidence-Based Practice Center (RTI–UNC EPC) to update its 2003 systematic literature review examining the effects of health literacy on health outcomes and interventions to improve those outcomes.

Objectives and Topic Nominator/Partner Information

AHRQ has requested an update to the 2004 systematic review Literacy and Health Outcomes. The original report and the report update were nominated by the AMA. The report will be based on a comprehensive and systematic review of the scientific literature, including extensive peer review of the draft report.

The RTI-UNC EPC was selected to conduct the original systematic review and update and develop the resulting reports. Experts from fields related to health literacy have been asked to serve as members of the Technical Expert Panel (TEP) and include experts in primary care, health education, clear language materials development, and health literacy measurement, research, and interventions. TEP input will help guide the systematic review of the literature.

The systematic review, published in 2004, analyzed the relationship between literacy and health outcomes and examined interventions that mitigate the health effects of low literacy. This update of the 2004 systematic review will be conducted to review additional literature to further our understanding of the relationship between health literacy (including not only print literacy, as was the focus of the earlier report, but also oral literacy and numeracy) and health outcomes and to understand what interventions are effective in mitigating the effect of low health literacy on health outcomes.

The Key Questions

Exhibit 2-1 provides two key questions (KQs) that will be used to guide the systematic review. Each question has 4 parts. One search will be conducted for each of the key questions. Parts c and d are derivative of the other key questions and will not have a separate literature search.

Exhibit 2-1. Key Questions for the Health Literacy Systematic Review

Key Question 1: Are health literacy skills related to

1. Use of health care services?
2. Health outcomes?
3. Costs of health care?
4. Disparities in health outcomes or health care service use according to race, ethnicity, culture, or age?

Key Question 2: For individuals with low health literacy skills, what are effective interventions to

1. Improve use of health care services?
2. Improve health outcomes?
3. Affect the costs of health care?
4. Improve health outcomes and/or health care service use among different racial, ethnic, cultural, or age groups?

PICOTS were used to define each key question as follows:

• KQ1
  • Population: Individuals and caregivers of all races and ethnicities
  • Intervention: Outcomes studies and so no applicable
  • Comparison: Studies compare outcomes among individuals with different levels of low health literacy and numeracy skills
  • Outcomes: Any health outcome with the exception of knowledge in those with low literacy (but not numeracy) because the prior relationship was considered well-established through the earlier review
  • Time: Articles are included that were published from 2003 forward for literacy and no time specification for numeracy. Studies may be cross-sectional or may follow individuals over varying lengths of time.
  • Setting: No exclusions. Individuals may be followed who are patients in the health care system or may be interviewed as part of a community-based study.
• KQ2
  • Population: Individuals and caregivers of all races and ethnicities with low health literacy
  • Intervention: All interventions intended to improve the use of health care services or health outcomes in low literacy or numeracy individuals; this includes, but is not limited to, interventions addressing patient/provider communication and barriers to health care, self-efficacy, or behavior change.
  • Comparison: Any comparator designated by the investigators, although a comparator is not necessary as long as pre-post intervention measures have been made.
  • Outcomes: Any health related outcome associated with literacy and/or numeracy skills.
  • Time: Articles are included that were published from 2003 forward for literacy and no time specification for numeracy. Studies may be cross-sectional or may follow individuals over varying lengths of time.
  • Setting: No exclusions. Individuals may be followed who are patients in the health care system or may be interviewed as part of a community-based study.

Analytic Framework

Exhibit 3-1 gives an overview of the analytic framework for our key questions. Exhibit 3-2 outlines a more detailed logic model explicating outcomes to be included in our review and their conceptual relationship to each other. This more detailed model will be used to determine whether articles considered for inclusion have relevant health outcomes. It will also guide our analysis of included articles.

For KQ 1a or 2a, we will consider any process of care as a health service, including clinic and hospital visits, hospitalizations, and use of preventive health care and screening services.

For KQ 1b and 2b, we use the term ‘health outcomes’ broadly to encompass both intermediate and more distal outcomes.

Exhibit 3-1. Analytic Framework for the Health Literacy Systematic Review

Exhibit 3-2. Logic Model for the Health Literacy Systematic Review

• Knowledge. We consider knowledge as a final outcome only in relation to intervention studies (KQ2) because evidence in the earlier review clearly concluded that there is a positive relationship between greater health literacy skills and higher knowledge levels (KQ1).
• Self-efficacy: Self-efficacy, a person’s confidence in their ability to carry out a health behavior, is an important intermediate outcome in many behavioral theoretical models and is a predictor of behavioral intent. Several researchers have hypothesized a link between self-efficacy and literacy.
• Behavioral Intent: Behavioral intent is a person’s stated likelihood of starting a behavior and is an important intermediate step in the causal pathway between low health literacy and health outcomes.
• Skills and Behavior: The relationship between health literacy and intermediate and distal outcomes depends on a person’s health skills and behavior. Skills include a person’s ability to recognize an emergency, seek additional health information and access health care. Behaviors include taking medication, changing one’s lifestyle, or monitoring one’s health.
• Adherence: Adherence is the ability to stick with a health behavior and is important predictor of health outcomes.
• Biochemical or biometric health outcomes. Biochemical or biometric measures such as blood pressure or glycosylated hemoglobin (HbA1c) can be important intermediate markers of more tangible health outcomes.
• Measures of disease incidence, prevalence, morbidity, and mortality. This category includes such outcomes as stage of cancer presentation, arthritis disease severity, diabetes control, and death rates. These are the ultimate outcomes the health care community is trying to affect.
• General health status. This outcome includes general measures of health status, usually assessed by self-report questionnaires that have been shown to predict health outcomes.
• Use of health care services. Health care services include clinic, hospital, and emergency room visits, and receipt of tests such as mammography and colonoscopy.

For KQ 1c measuring the cost of health care, we will include any study that measured the monetary cost of health care services. For KQ 2c, we will also include studies measuring the cost of the intervention. Finally, to address KQ 1d and 2d, concerning disparities in health outcomes and use of health care services, we will look for studies that report on the mediation of the relationship between race, ethnicity, culture, or age and health outcomes (or the effectiveness of interventions) by health literacy. We will also include studies that report on variables, such as race, ethnicity, culture or age, examined as moderators of the relationship between literacy and health outcomes.

Solid lines show the relationship between low health literacy and outcomes (KQ1), while dotted lines show the effect of interventions on low health literacy (KQ2).

Methods

A. Criteria for Inclusion/Exclusion of Studies in the Review

Exhibit 4-1 presents the inclusion/exclusion criteria we will use during abstract and full text review.

B. Searching for the Evidence: Literature Search Strategies for Identification of Relevant Studies to Answer the Key Questions

We will systematically search, review, and analyze the scientific evidence for each key question. The steps that we will take to accomplish the literature review are described below.

To identify the relevant literature for our review, we began with a focused MEDLINE search using a variety of terms, limited to English and human-only studies. We conducted key word searches since no MeSH headings specifically identify health literacy-related articles. The terms “health literacy,” “numeracy,” “literacy [tw]” and instruments known to measure health literacy were the focus of the search. We limited the “health literacy” and “literacy [tw]” searches to 2003 forward to be confident that we do not miss studies between the first review and this update and to not unnecessarily overlap with the literature reviewed earlier.

We also searched other databases (Cumulative Index to Nursing and Allied Health (CINAHL), the Cochrane Library, PSYCINFO, and the Educational Resources Information Center (ERIC)) which include articles concerning a variety of literacy issues. We used “health literacy” to narrow the search to articles of interest. Results from initial database searches are presented in Exhibit 4-2.

Exhibit 4-2. Results of Literature Search

Our initial searches yielded 2,855 citations across databases. We reviewed our search strategy with the TEP and will supplement as needed according to any future recommendations. In addition, to attempt to avoid retrieval bias, we will manually search the reference lists of landmark studies and background articles on this topic to look for any relevant citations that might have been missed by electronic searches. We will also conduct an updated literature search before completing the final draft of the report. We do not anticipate incorporating gray literature in this search.

C. Data Abstraction and Data Management

We will review all titles and abstracts identified through searches against our inclusion/exclusion criteria. Each abstract will be independently reviewed by two members of the team. When differences arise between the reviewers, we will include studies for full-text review. For studies without adequate information to make the determination, we will again review the full text. All results will be tracked in an EndNote database.

We will retrieve the full text of all titles included during abstract review. Each full-text article will be independently reviewed by two members of the team for inclusion or exclusion based on the eligibility criteria described above. If both reviewers agree that a study does not meet the eligibility criteria, the study will be excluded. If the reviewers disagree, conflicts will be resolved by discussion and consensus or by consulting a third, independent party. As above, all results will be tracked in an EndNote database including, where applicable, the reason a study did not satisfy eligibility criteria so that we can later compile a listing of excluded articles and reasons for such exclusions.

We will design evidence tables that identify study information including study design, methods, and results. Trained abstractors will extract the relevant data from each included article into preformatted tables. Data abstractions will be reviewed for accuracy by a senior member of the team. We will create two sets of evidence tables, one for KQ 1 and one for KQ 2. The format of the tables will vary slightly by key question; in particular, the tables for KQ 2 will include a column that describes the intervention.

For this work, the RTI-UNC EPC team decided to abstract data from included articles directly into evidence tables, in part because most staff members had prior experience conducting evidence-based systematic reviews for AHRQ. This decision means that we bypass the use of data abstraction forms. Following this approach will create efficiencies in production and will not result in any major changes in the type of information included in the evidence tables as the project progresses.

D. Assessment of Methodological Quality of Individual Studies

To assess the quality (internal validity) of studies, we will use predefined criteria based on those developed for the earlier review, by the US Preventive Services Task Force (ratings: good, fair, poor) and the National Health Service Centre for Reviews and Dissemination and methods expertise available through our own and other EPCs (Berkman et al., 2004). In general terms, a “good” study has the least bias and results are considered to be valid. A “fair” study is susceptible to some bias but probably not sufficient to invalidate its results. A “poor” rating indicates significant bias (e.g., stemming from serious errors in design or analysis) that may invalidate the study’s results. We will update the methodology used in our earlier study as necessary after reviewing recent criteria developed by the RAND EPC to evaluate bias in randomized controlled trials and recently developed criteria on the quality of observational studies developed by Nancy Berkman and Meera Viswanathan at the RTI-UNC EPC.

Two independent reviewers will assign quality ratings to each study. Disagreements will be resolved by discussion and consensus or by consulting a third, independent party.

E. Data Synthesis

We anticipate that the data found in the literature review will be synthesized qualitatively. We do not anticipate that we will have a sufficient number of studies with similar outcomes or similar interventions to improve health outcomes in a population of individuals with low health literacy to consider quantitative analysis (meta-analysis) of data from those studies.

F. Grading the Evidence for Each Key Question

We will rate the strength of evidence based on the standard methods of the EPCs, which use a revised version of the approach devised by the GRADE working group (Atkins et al., 2004). Developed to grade the quality of evidence and the strength of recommendations, this approach incorporates the following elements: study design, study quality, consistency, directness, presence of imprecise or sparse data, high probability of publication bias, and magnitude of the effect. We use four grades: high, moderate, low, and insufficient.

References

An initial list of key authors and citations which met our inclusion criteria upon full article review appear in Appendix A. Some of these studies may be excluded upon more detailed dual review and additional articles are likely to be added when the literature review is updated.

Summary of Protocol Amendments

In the event of protocol amendments, the date of each amendment will be accompanied by a description of the change and the rationale.

NOTE: The following protocol elements are standard procedures for all protocols.

Review of Key Questions

Key questions submitted by partners are reviewed and refined as needed by the EPC and the TEP to ensure that the questions are specific and explicit about what information is being reviewed.

Technical Expert Panel

A TEP is selected to provide broad expertise and perspectives specific to the topic under development. Divergent and conflicted opinions are common and perceived as healthy scientific discourse that results in a thoughtful, relevant systematic review. Therefore, study questions, design, and/or methodological approaches do not necessarily represent the views of individual technical and content experts. The TEP provides information to the EPC to identify literature search strategies, reviews the draft report, and recommends approaches to specific issues as requested by the EPC. The TEP does not do analysis of any kind nor contribute to the writing of the report.

Peer Review

Approximately five experts in the field will be asked to peer review the draft report and provide comments. The peer reviewer may represent stakeholder groups such as professional or advocacy organizations with knowledge of the topic. Peer review comments on the preliminary draft of the report are considered by the EPC in preparation of the final draft of the report. The synthesis of the scientific literature presented in the final report does not necessarily represent the views of individual reviewers. The dispositions of the peer review comments are documented and will be published three months after the publication of the evidence report with the reviewer identification information removed.

It is our policy not to release the names of the peer reviewers or TEP panel members until the report is published so that they can maintain their objectivity during the review process.

References

Berkman ND, DeWalt DA, Pignone MP, et al. Literacy and health outcomes. Rockville, MD: Agency for Healthcare Research and Quality. 2004. http://www.ahrq.gov/clinic/tp/littp.htm.

DeWalt, D. A., N. D. Berkman, S. Sheridan, K. N. Lohr, and M. P. Pignone. 2004a. Literacy and health outcomes: A systematic review of the literature. Journal of General Internal Medicine 19(12):1228-1239.

Kutner, M., Greenberg, E., Jin, Y., & Paulsen, C. (2006). The health literacy of America’s adults: Results from the 2003 National Assessment of Adult Literacy (NCES 2006-483). U.S. Department of Education, National Center for Education Statistics, Washington, D.C.: U.S. Government Printing Office.

Sudore RL, Yaffe K, Satterfield S, Harris TB, Mehta KM, Simonsick EM, Newman AB, Rosano C, Rooks R, Rubin SM, Ayonayon HN, Schillinger D. Limited literacy and mortality in the elderly: the health, aging, and body composition study. J Gen Intern Med. 2006 Aug; 21(8): 806-12.

APPENDIX A: Preliminary List of Citations Meeting Our Inclusion Criteria

Key Question 1:
Aggarwal, A., J. L. Speckman, et al. (2007). "The role of numeracy on cancer screening among urban women." Am J Health Behav 31 Suppl 1: S57-68.

Aikens, J. E. and J. D. Piette (2009). "Diabetic patients' medication underuse, illness outcomes, and beliefs about antihyperglycemic and antihypertensive treatments." Diabetes Care 32(1): 19-24.

Apter, A. J., J. Cheng, et al. (2006). "Asthma numeracy skill and health literacy." J Asthma 43(9): 705-10.

Arozullah, A. M., S. Y. Lee, et al. (2006). "The roles of low literacy and social support in predicting the preventability of hospital admission." J Gen Intern Med 21(2): 140-5.

Baker, D. W., J. A. Gazmararian, et al. (2004). "Health literacy and use of outpatient physician services by Medicare managed care enrollees." J Gen Intern Med 19(3): 215-20.

Baker, D. W., M. S. Wolf, et al. (2007). "Health literacy and mortality among elderly persons." Arch Intern Med 167(14): 1503-9.

Baker, D. W., M. S. Wolf, et al. (2008). "Health literacy, cognitive abilities, and mortality among elderly persons." J Gen Intern Med 23(6): 723-6.

Barnes, D. E., I. B. Tager, et al. (2004). "The relationship between literacy and cognition in well-educated elders." J Gerontol A Biol Sci Med Sci 59(4): 390-5.

Barragan, M., G. Hicks, et al. (2005). "Low health literacy is associated with HIV test acceptance." J Gen Intern Med 20(5): 422-5.

Bautista, R. E., E. T. Glen, et al. (2009). "The association between health literacy and outcomes of care among epilepsy patients." Seizure 18(6): 400-4.

Bennett, I. M., J. Chen, et al. (2009). "The contribution of health literacy to disparities in self-rated health status and preventive health behaviors in older adults." Ann Fam Med 7(3): 204-11.

Bennett, I. M., J. F. Culhane, et al. (2007). "Literacy and depressive symptomatology among pregnant Latinas with limited English proficiency." Am J Orthopsychiatry 77(2): 243-8.

Bennett, I., J. Switzer, et al. (2006). "'Breaking it down': patient-clinician communication and prenatal care among African American women of low and higher literacy." Ann Fam Med 4(4): 334-40.

Campbell, M. J., M. J. Edwards, et al. (2007). "Developing a parsimonious model for predicting completion of advance directives." J Nurs Scholarsh 39(2): 165-71.

Carroll, J. M., B. Maughan, et al. (2005). "Literacy difficulties and psychiatric disorders: evidence for comorbidity." J Child Psychol Psychiatry 46(5): 524-32.

Cavanaugh, K., M. M. Huizinga, et al. (2008). "Association of numeracy and diabetes control." Ann Intern Med 148(10): 737-46.

Chew, L. D., K. A. Bradley, et al. (2004). "The impact of low health literacy on surgical practice." Am J Surg 188(3): 250-3.

Cho, Y. I., S. Y. Lee, et al. (2008). "Effects of health literacy on health status and health service utilization amongst the elderly." Soc Sci Med 66(8): 1809-16.

Clarke, C., S. M. Friedman, et al. (2005). "Emergency department discharge instructions comprehension and compliance study." Cjem 7(1): 5-11.

Coldren, R. L., T. Prosser, et al. (2006). "Literacy and recent history of diarrhoea are predictive of Plasmodium falciparum parasitaemia in Kenyan adults." Malar J 5: 96.

Conwell, L. S., M. J. O'Callaghan, et al. (2003). "Early adolescent smoking and a web of personal and social disadvantage." J Paediatr Child Health 39(8): 580-5.

Davids, S. L., M. M. Schapira, et al. (2004). "Predictors of pessimistic breast cancer risk perceptions in a primary care population." J Gen Intern Med 19(4): 310-5.

Davis, T. C., D. D. Fredrickson, et al. (2006). "Patient understanding and use of oral contraceptive pills in a southern public health family planning clinic." South Med J 99(7): 713-8.

Davis, T. C., M. S. Wolf, et al. (2006). "Literacy and misunderstanding prescription drug labels." Ann Intern Med 145(12): 887-94.

DeWalt, D. A., M. H. Dilling, et al. (2007). "Low parental literacy is associated with worse asthma care measures in children." Ambul Pediatr 7(1): 25-31.

DeWalt, D. A., R. S. Boone, et al. (2007). "Literacy and its relationship with self-efficacy, trust, and participation in medical decision making." Am J Health Behav 31 Suppl 1: S27-35.

Drainoni, M. L., S. Rajabiun, et al. (2008). "Health literacy of HIV-positive individuals enrolled in an outreach intervention: results of a cross-site analysis." J Health Commun 13(3): 287-302.

Elliott, C. and K. Farmer (2006). "Immunization status of children under 7 years in the Vikas Nagar area, North India." Child Care Health Dev 32(4): 415-21.

Endres, L. K., L. K. Sharp, et al. (2004). "Health literacy and pregnancy preparedness in pregestational diabetes." Diabetes Care 27(2): 331-4.

Estrada, C. A., M. Martin-Hryniewicz, et al. (2004). "Literacy and numeracy skills and anticoagulation control." Am J Med Sci 328(2): 88-93.

Fang, M. C., E. L. Machtinger, et al. (2006). "Health literacy and anticoagulation-related outcomes among patients taking warfarin." J Gen Intern Med 21(8): 841-6.

Federman, A. D., D. G. Safran, et al. (2009). "Awareness of pharmaceutical cost-assistance programs among inner-city seniors." Am J Geriatr Pharmacother 7(2): 117-29.

Garbers, S. and M. A. Chiasson (2004). "Inadequate functional health literacy in Spanish as a barrier to cervical cancer screening among immigrant Latinas in New York City." Prev Chronic Dis 1(4): A07.

Gazmararian, J. A., S. Kripalani, et al. (2006). "Factors associated with medication refill adherence in cardiovascular-related diseases: a focus on health literacy." J Gen Intern Med 21(12): 1215-21.

Gerber, B. S., M. Pagcatipunan, et al. (2006). "The assessment of diabetes knowledge and self-efficacy in a diverse population using Rasch measurement." J Appl Meas 7(1): 55-73.

Ginde, A. A., S. Clark, et al. (2008). "Demographic disparities in numeracy among emergency department patients: evidence from two multicenter studies." Patient Educ Couns 72(2): 350-6.

Ginde, A. A., S. G. Weiner, et al. (2008). "Multicenter study of limited health literacy in emergency department patients." Acad Emerg Med 15(6): 577-80.

Graham, J., I. M. Bennett, et al. (2007). "Medication beliefs as mediators of the health literacy-antiretroviral adherence relationship in HIV-infected individuals." AIDS Behav 11(3): 385-92.

Grubbs, V., S. E. Gregorich, et al. (2009). "Health literacy and access to kidney transplantation." Clin J Am Soc Nephrol 4(1): 195-200.

Guerra, C. E., F. Dominguez, et al. (2005). "Literacy and knowledge, attitudes, and behavior about colorectal cancer screening." J Health Commun 10(7): 651-63.

Guerra, C. E., M. Krumholz, et al. (2005). "Literacy and knowledge, attitudes and behavior about mammography in Latinas." J Health Care Poor Underserved 16(1): 152-66.

Haggstrom, D. A. and M. M. Schapira (2006). "Black-white differences in risk perceptions of breast cancer survival and screening mammography benefit." J Gen Intern Med 21(4): 371-7.

Hahn, E. A., D. Cella, et al. (2007). "The impact of literacy on health-related quality of life measurement and outcomes in cancer outpatients." Qual Life Res 16(3): 495-507.

Hawley, S. T., B. Zikmund-Fisher, et al. (2008). "The impact of the format of graphical presentation on health-related knowledge and treatment choices." Patient Educ Couns 73(3): 448-55.

Hawley, S. T., N. K. Janz, et al. (2008). "Latina patient perspectives about informed treatment decision making for breast cancer." Patient Educ Couns 73(2): 363-70.

Hetherington, R., M. Dennis, et al. (2006). "Functional outcome in young adults with spina bifida and hydrocephalus." Childs Nerv Syst 22(2): 117-24.

Hibbard, J. H., E. Peters, et al. (2007). "Consumer competencies and the use of comparative quality information: it isn't just about literacy." Med Care Res Rev 64(4): 379-94.

Hironaka, L. K., M. K. Paasche-Orlow, et al. (2009). "Caregiver health literacy and adherence to a daily multi-vitamin with iron regimen in infants." Patient Educ Couns 75(3): 376-80.

Hope, C. J., J. Wu, et al. (2004). "Association of medication adherence, knowledge, and skills with emergency department visits by adults 50 years or older with congestive heart failure." Am J Health Syst Pharm 61(19): 2043-9.

Howard, D. H., J. Gazmararian, et al. (2005). "The impact of low health literacy on the medical costs of Medicare managed care enrollees." Am J Med 118(4): 371-7.

Howard, D. H., T. Sentell, et al. (2006). "Impact of health literacy on socioeconomic and racial differences in health in an elderly population." J Gen Intern Med 21(8): 857-61.

Huizinga, M. M., B. M. Beech, et al. (2008). "Low numeracy skills are associated with higher BMI." Obesity (Silver Spring) 16(8): 1966-8.

Hwang, S. W., C. Q. Tram, et al. (2005). "The effect of illustrations on patient comprehension of medication instruction labels." BMC Fam Pract 6(1): 26.

Ishikawa, H., K. Nomura, et al. (2008). "Developing a measure of communicative and critical health literacy: a pilot study of Japanese office workers." Health Promot Int 23(3): 269-74.

Ives, T. J., P. R. Chelminski, et al. (2006). "Predictors of opioid misuse in patients with chronic pain: a prospective cohort study." BMC Health Serv Res 6: 46.

Johnston, M. V., M. E. Diab, et al. (2005). "Health literacy, morbidity, and quality of life among individuals with spinal cord injury." J Spinal Cord Med 28(3): 230-40.

Jones, M., J. Y. Lee, et al. (2007). "Oral health literacy among adult patients seeking dental care." J Am Dent Assoc 138(9): 1199-208; quiz 1266-7.

Juzych, M. S., S. Randhawa, et al. (2008). "Functional health literacy in patients with glaucoma in urban settings." Arch Ophthalmol 126(5): 718-24.

Kalanda, B. F., S. van Buuren, et al. (2005). "Catch-up growth in Malawian babies, a longitudinal study of normal and low birthweight babies born in a malarious endemic area." Early Hum Dev 81(10): 841-50.

Kalichman, S. C., C. M. Amaral, et al. (2007). "Adherence to antiretroviral therapy assessed by unannounced pill counts conducted by telephone." J Gen Intern Med 22(7): 1003-6.

Kalichman, S. C., H. Pope, et al. (2008). "Association between health literacy and HIV treatment adherence: further evidence from objectively measured medication adherence." J Int Assoc Physicians AIDS Care (Chic Ill) 7(6): 317-23.

Kalichman, S. C., S. Catz, et al. (1999). "Barriers to HIV/AIDS treatment and treatment adherence among African-American adults with disadvantaged education." J Natl Med Assoc 91(8): 439-46.

Kelly, P. A. and P. Haidet (2007). "Physician overestimation of patient literacy: a potential source of health care disparities." Patient Educ Couns 66(1): 119-22.

Khan, N. Z., H. Muslima, et al. (2006). "Neurodevelopmental outcomes of preterm infants in Bangladesh." Pediatrics 118(1): 280-9.

Kim, S., F. Love, et al. (2004). "Association of health literacy with self-management behavior in patients with diabetes." Diabetes Care 27(12): 2980-2.

Kleinpeter, M. A. (2003). "Health literacy affects peritoneal dialysis performance and outcomes." Adv Perit Dial 19: 115-9.

Koch-Weser, S., S. L. Liang, et al. (2006). "Self-reported health among Cambodians in Lowell, Massachusetts." J Health Care Poor Underserved 17(2 Suppl): 133-45.

Kollipara, U. K., O. Jaffer, et al. (2008). "Relation of lack of knowledge about dietary sodium to hospital readmission in patients with heart failure." Am J Cardiol 102(9): 1212-5.

Kripalani, S., L. E. Henderson, et al. (2006). "Predictors of medication self-management skill in a low-literacy population." J Gen Intern Med 21(8): 852-6.

Laramee, A. S., N. Morris, et al. (2007). "Relationship of literacy and heart failure in adults with diabetes." BMC Health Serv Res 7: 98.

Lee, S.-Y. D., A. M. Arozullah, et al. (2009). "Health literacy, social support, and health status among older adults." Educational Gerontology 35(3): 191-201.

LeVine, R. A., S. E. LeVine, et al. (2004). "Maternal literacy and health behavior: a Nepalese case study." Soc Sci Med 58(4): 863-77.

Lillie, S. E., N. T. Brewer, et al. (2007). "Retention and use of breast cancer recurrence risk information from genomic tests: the role of health literacy." Cancer Epidemiol Biomarkers Prev 16(2): 249-55.

Lincoln, A., D. Espejo, et al. (2008). "Limited literacy and psychiatric disorders among users of an urban safety-net hospital's mental health outpatient clinic." J Nerv Ment Dis 196(9): 687-93.

Lincoln, A., M. K. Paasche-Orlow, et al. (2006). "Impact of health literacy on depressive symptoms and mental health-related: quality of life among adults with addiction." J Gen Intern Med 21(8): 818-22.

Lindau, S. T., A. Basu, et al. (2006). "Health literacy as a predictor of follow-up after an abnormal Pap smear: a prospective study." J Gen Intern Med 21(8): 829-34.

Mancuso, C. A. and M. Rincon (2006). "Asthma patients' assessments of health care and medical decision making: the role of health literacy." J Asthma 43(1): 41-4.

Mancuso, C. A. and M. Rincon (2006). "Impact of health literacy on longitudinal asthma outcomes." J Gen Intern Med 21(8): 813-7.

Marteleto, L., D. Lam, et al. (2008). "Sexual behavior, pregnancy, and schooling among young people in urban South Africa." Stud Fam Plann 39(4): 351-68.

Mayben, J. K., J. R. Kramer, et al. (2007). "Predictors of delayed HIV diagnosis in a recently diagnosed cohort." AIDS Patient Care STDS 21(3): 195-204.

McDade, T. W., W. R. Leonard, et al. (2005). "Predictors of C-reactive protein in Tsimane' 2 to 15 year-olds in lowland Bolivia." Am J Phys Anthropol 128(4): 906-13.

Miller, D. P., Jr., C. D. Brownlee, et al. (2007). "The effect of health literacy on knowledge and receipt of colorectal cancer screening: a survey study." BMC Fam Pract 8: 16.

Miller, E. A. and D. M. West (2007). "Characteristics associated with use of public and private web sites as sources of health care information: results from a national survey." Med Care 45(3): 245-51.

Morris, N. S., C. D. MacLean, et al. (2006). "Literacy and health outcomes: a cross-sectional study in 1002 adults with diabetes." BMC Fam Pract 7: 49.

Morrow, D., D. Clark, et al. (2006). "Correlates of health literacy in patients with chronic heart failure." Gerontologist 46(5): 669-76.

Muir, K. W., C. Santiago-Turla, et al. (2006). "Health literacy and adherence to glaucoma therapy." Am J Ophthalmol 142(2): 223-6.

Muir, K. W., C. Santiago-Turla, et al. (2008). "Health literacy and vision-related quality of life." Br J Ophthalmol 92(6): 779-82.

Murray, M. D., W. Tu, et al. (2009). "Factors associated with exacerbation of heart failure include treatment adherence and health literacy skills." Clin Pharmacol Ther 85(6): 651-8.

Nokes, K. M., C. L. Coleman, et al. (2007). "Health literacy and health outcomes in HIV seropositive persons." Res Nurs Health 30(6): 620-7.

Osborn, C. Y., M. K. Paasche-Orlow, et al. (2007). "Health literacy: an overlooked factor in understanding HIV health disparities." Am J Prev Med 33(5): 374-8.

Paasche-Orlow, M. K., D. M. Cheng, et al. (2006). "Health literacy, antiretroviral adherence, and HIV-RNA suppression: a longitudinal perspective." J Gen Intern Med 21(8): 835-40.

Paasche-Orlow, M. K., J. G. Clarke, et al. (2005). "Educational attainment but not literacy is associated with HIV risk behavior among incarcerated women." J Womens Health (Larchmt) 14(9): 852-9.

Paasche-Orlow, M. K., K. A. Riekert, et al. (2005). "Tailored education may reduce health literacy disparities in asthma self-management." Am J Respir Crit Care Med 172(8): 980-6.

Pandit, A. U., J. W. Tang, et al. (2009). "Education, literacy, and health: Mediating effects on hypertension knowledge and control." Patient Educ Couns 75(3): 381-5.

Persell, S. D., C. Y. Osborn, et al. (2007). "Limited health literacy is a barrier to medication reconciliation in ambulatory care." J Gen Intern Med 22(11): 1523-6.

Peterson, N. B., K. A. Dwyer, et al. (2007). "The influence of health literacy on colorectal cancer screening knowledge, beliefs and behavior." J Natl Med Assoc 99(10): 1105-12.

Pieper, B., M. Sieggreen, et al. (2007). "Discharge knowledge and concerns of patients going home with a wound." J Wound Ostomy Continence Nurs 34(3): 245-53; quiz 254-5.

Powell, C. K., E. G. Hill, et al. (2007). "The relationship between health literacy and diabetes knowledge and readiness to take health actions." Diabetes Educ 33(1): 144-51.

Powers, B. J., M. K. Olsen, et al. (2008). "Literacy and blood pressure--do healthcare systems influence this relationship? A cross-sectional study." BMC Health Serv Res 8: 219.

Prior, M., D. Smart, et al. (1999). "Relationships between learning difficulties and psychological problems in preadolescent children from a longitudinal sample." J Am Acad Child Adolesc Psychiatry 38(4): 429-36.

Raehl, C. L., C. A. Bond, et al. (2006). "Screening tests for intended medication adherence among the elderly." Ann Pharmacother 40(5): 888-93.

Roth, M. T. and J. L. Ivey (2005). "Self-reported medication use in community-residing older adults: A pilot study." Am J Geriatr Pharmacother 3(3): 196-204.

Rothman, R. L., R. Housam, et al. (2006). "Patient understanding of food labels: the role of literacy and numeracy." Am J Prev Med 31(5): 391-8.

Sanders, L. M., V. T. Thompson, et al. (2007). "Caregiver health literacy and the use of child health services." Pediatrics 119(1): e86-92.

Sarkar, K., B. Bal, et al. (2006). "Young age is a risk factor for HIV among female sex workers--an experience from India." J Infect 53(4): 255-9.

Sarkar, U., L. Fisher, et al. (2006). "Is self-efficacy associated with diabetes self-management across race/ethnicity and health literacy?" Diabetes Care 29(4): 823-9.

Schillinger, D., J. Piette, et al. (2003). "Closing the loop: physician communication with diabetic patients who have low health literacy." Arch Intern Med 163(1): 83-90.

Schillinger, D., L. R. Barton, et al. (2006). "Does literacy mediate the relationship between education and health outcomes? A study of a low-income population with diabetes." Public Health Rep 121(3): 245-54.

Schwartz, L. M., S. Woloshin, et al. (1997). "The role of numeracy in understanding the benefit of screening mammography." Ann Intern Med 127(11): 966-72.

Schwartz, S. R., J. McDowell, et al. (2004). "Numeracy and the shortcomings of utility assessment in head and neck cancer patients." Head Neck 26(5): 401-7.

Seligman, H. K., F. F. Wang, et al. (2005). "Physician notification of their diabetes patients' limited health literacy. A randomized, controlled trial." J Gen Intern Med 20(11): 1001-7.

Sentell, T. L. and H. A. Halpin (2006). "Importance of adult literacy in understanding health disparities." J Gen Intern Med 21(8): 862-6.

Sentell, T. L. and M. A. Shumway (2003). "Low literacy and mental illness in a nationally representative sample." J Nerv Ment Dis 191(8): 549-52.

Shone, L. P., K. M. Conn, et al. (2009). "The role of parent health literacy among urban children with persistent asthma." Patient Educ Couns 75(3): 368-75.

Smith, J. L. and J. Haggerty (2003). "Literacy in primary care populations: is it a problem?" Can J Public Health 94(6): 408-12.

Sudore, R. L., C. S. Landefeld, et al. (2009). "Unraveling the relationship between literacy, language proficiency, and patient-physician communication." Patient Educ Couns 75(3): 398-402.

Sudore, R. L., K. M. Mehta, et al. (2006). "Limited literacy in older people and disparities in health and healthcare access." J Am Geriatr Soc 54(5): 770-6.

Sudore, R. L., K. Yaffe, et al. (2006). "Limited literacy and mortality in the elderly: the health, aging, and body composition study." J Gen Intern Med 21(8): 806-12.

Tang, Y. H., S. M. Pang, et al. (2008). "Health literacy, complication awareness, and diabetic control in patients with type 2 diabetes mellitus." J Adv Nurs 62(1): 74-83.

Tokuda, Y., N. Doba, et al. (2009). "Health literacy and physical and psychological wellbeing in Japanese adults." Patient Educ Couns 75(3): 411-7.

Torres, R. Y. and R. Marks (2009). "Relationships among health literacy, knowledge about hormone therapy, self-efficacy, and decision-making among postmenopausal health." J Health Commun 14(1): 43-55.

van Servellen, G., F. Carpio, et al. (2003). "Program to enhance health literacy and treatment adherence in low-income HIV-infected Latino men and women." AIDS Patient Care STDS 17(11): 581-94.

van Tol-Geerdink, J. J., P. F. Stalmeier, et al. (2006). "Do prostate cancer patients want to choose their own radiation treatment?" Int J Radiat Oncol Biol Phys 66(4): 1105-11.

Vavrus, F. (2006). "Girls' schooling in Tanzania: the key to HIV/AIDS prevention?" AIDS Care 18(8): 863-71.

von Wagner, C., K. Knight, et al. (2007). "Functional health literacy and health-promoting behaviour in a national sample of British adults." J Epidemiol Community Health 61(12): 1086-90.

Waite, K. R., M. Paasche-Orlow, et al. (2008). "Literacy, social stigma, and HIV medication adherence." J Gen Intern Med 23(9): 1367-72.

Waldrop-Valverde, D., D. L. Jones, et al. (2008). "The effects of low literacy and cognitive impairment on medication adherence in HIV-positive injecting drug users." AIDS Care 20(10): 1202-10.

Walker, D., A. Adebajo, et al. (2007). "Patient education in rheumatoid arthritis: the effectiveness of the ARC booklet and the mind map." Rheumatology (Oxford) 46(10): 1593-6.

Wallace, L. S., E. S. Rogers, et al. (2008). "Relationship between health literacy and health-related quality of life among Tennesseans." Tenn Med 101(5): 35-9.

Weiss, B. D. and R. Palmer (2004). "Relationship between health care costs and very low literacy skills in a medically needy and indigent Medicaid population." J Am Board Fam Pract 17(1): 44-7.

White, S., J. Chen, et al. (2008). "Relationship of preventive health practices and health literacy: a national study." Am J Health Behav 32(3): 227-42.

Wilson, F. L., L. M. Baker, et al. (2008). "Using the teach-back and Orem's Self-care Deficit Nursing theory to increase childhood immunization communication among low-income mothers." Issues Compr Pediatr Nurs 31(1): 7-22.

Wolf, M. S., J. A. Gazmararian, et al. (2005). "Health literacy and functional health status among older adults." Arch Intern Med 165(17): 1946-52.

Wolf, M. S., J. A. Gazmararian, et al. (2007). "Health literacy and health risk behaviors among older adults." Am J Prev Med 32(1): 19-24.

Wolf, M. S., M. V. Williams, et al. (2007). "Patients' shame and attitudes toward discussing the results of literacy screening." J Health Commun 12(8): 721-32.

Wolf, M. S., S. J. Knight, et al. (2006). "Literacy, race, and PSA level among low-income men newly diagnosed with prostate cancer." Urology 68(1): 89-93.

Wolf, M. S., T. C. Davis, et al. (2004). "Health literacy and patient knowledge in a Southern US HIV clinic." Int J STD AIDS 15(11): 747-52.

Wolf, M. S., T. C. Davis, et al. (2006). "A critical review of FDA-approved Medication Guides." Patient Educ Couns 62(3): 316-22.

Wolf, M. S., T. C. Davis, et al. (2006). "Misunderstanding of prescription drug warning labels among patients with low literacy." Am J Health Syst Pharm 63(11): 1048-55.

Wolf, M. S., T. C. Davis, et al. (2007). "Literacy, self-efficacy, and HIV medication adherence." Patient Educ Couns 65(2): 253-60.

Wolf, M. S., T. C. Davis, et al. (2007). "To err is human: patient misinterpretations of prescription drug label instructions." Patient Educ Couns 67(3): 293-300.

Wright, A. J., S. C. Whitwell, et al. (2009). "The impact of numeracy on reactions to different graphic risk presentation formats: An experimental analogue study." Br J Health Psychol 14(Pt 1): 107-25.

Yin, H. S., B. P. Dreyer, et al. (2007). "Association of low caregiver health literacy with reported use of nonstandardized dosing instruments and lack of knowledge of weight-based dosing." Ambul Pediatr 7(4): 292-8.

Zazove, P., H. E. Meador, et al. (2006). "Assessment of depressive symptoms in deaf persons." J Am Board Fam Med 19(2): 141-7.

Key Question 2:

Bickmore, T. W., L. M. Pfeifer, et al. (2009). "Using computer agents to explain medical documents to patients with low health literacy." Patient Educ Couns 75(3): 315-20.

Bosworth, H. B., M. K. Olsen, et al. (2005). "Nurse administered telephone intervention for blood pressure control: a patient-tailored multifactorial intervention." Patient Educ Couns 57(1): 5-14.

Brock, T. P. and S. R. Smith (2007). "Using digital videos displayed on personal digital assistants (PDAs) to enhance patient education in clinical settings." Int J Med Inform 76(11-12): 829-35.

Campbell, F. A., B. D. Goldman, et al. (2004). "The effect of format modifications and reading comprehension on recall of informed consent information by low-income parents: a comparison of print, video, and computer-based presentations." Patient Educ Couns 53(2): 205-16.

Carbone, E. T., K. M. Lennon, et al. (2006). "Testing the feasibility of an interactive learning styles measure for U.S. Latino Adults with type 2 diabetes and low literacy." International Quarterly of Community Health Education 25(4): 315-335.

Coyne, C. A., R. Xu, et al. (2003). "Randomized, controlled trial of an easy-to-read informed consent statement for clinical trial participation: a study of the Eastern Cooperative Oncology Group." J Clin Oncol 21(5): 836-42.

Davis, T. C., M. S. Wolf, et al. (2008). "Provider and patient intervention to improve weight loss: a pilot study in a public hospital clinic." Patient Educ Couns 72(1): 56-62.

DeWalt, D. A., M. Pignone, et al. (2004). "Development and pilot testing of a disease management program for low literacy patients with heart failure." Patient Educ Couns 55(1): 78-86.

DeWalt, D. A., R. M. Malone, et al. (2006). "A heart failure self-management program for patients of all literacy levels: a randomized, controlled trial [ISRCTN11535170]." BMC Health Serv Res 6: 30.

Dewalt, D. A., T. C. Davis, et al. (2009). "Goal setting in diabetes self-management: Taking the baby steps to success." Patient Educ Couns.

Ferreira, M. R., N. C. Dolan, et al. (2005). "Health care provider-directed intervention to increase colorectal cancer screening among veterans: results of a randomized controlled trial." J Clin Oncol 23(7): 1548-54.

Geller, B. M., J. M. Skelly, et al. (2008). "Increasing patient/physician communications about colorectal cancer screening in rural primary care practices." Med Care 46(9 Suppl 1): S36-43.

Gerber, B. S., I. G. Brodsky, et al. (2005). "Implementation and evaluation of a low-literacy diabetes education computer multimedia application." Diabetes Care 28(7): 1574-80.

Green, M. J., S. K. Peterson, et al. (2004). "Effect of a computer-based decision aid on knowledge, perceptions, and intentions about genetic testing for breast cancer susceptibility: a randomized controlled trial." Jama 292(4): 442-52.

Greene, J., E. Peters, et al. (2008). "Comprehension and choice of a consumer-directed health plan: an experimental study." Am J Manag Care 14(6): 369-76.

Holzemer, W. L., S. Bakken, et al. (2006). "Testing a nurse-tailored HIV medication adherence intervention." Nurs Res 55(3): 189-97.

Kalichman, S. C., J. Cherry, et al. (2005). "Nurse-delivered antiretroviral treatment adherence intervention for people with low literacy skills and living with HIV/AIDS." J Assoc Nurses AIDS Care 16(5): 3-15.

Kandula, N. R., P. A. Nsiah-Kumi, et al. (2009). "The relationship between health literacy and knowledge improvement after a multimedia type 2 diabetes education program." Patient Educ Couns 75(3): 321-7.

Kelly, K. M., R. Shedlosky-Shoemaker, et al. (2007). "Cancer family history reporting: impact of method and psychosocial factors." J Genet Couns 16(3): 373-82.

Kripalani, S., J. Sharma, et al. (2007). "Low-literacy interventions to promote discussion of prostate cancer: a randomized controlled trial." Am J Prev Med 33(2): 83-90.

Kripalani, S., R. Bengtzen, et al. (2008). "Clinical research in low-literacy populations: using teach-back to assess comprehension of informed consent and privacy information." Irb 30(2): 13-9.

Kripalani, S., R. Robertson, et al. (2007). "Development of an illustrated medication schedule as a low-literacy patient education tool." Patient Educ Couns 66(3): 368-77.

Llewellyn, G., D. McConnell, et al. (2003). "Promoting health and home safety for children of parents with intellectual disability: a randomized controlled trial." Res Dev Disabil 24(6): 405-31.

Mayhorn, C. B. and R. C. Goldsworthy (2007). "Refining teratogen warning symbols for diverse populations." Birth Defects Res A Clin Mol Teratol 79(6): 494-506.

McGinn, T. and K. Allen (2006). "Improving refugees' reproductive health through literacy in Guinea." Glob Public Health 1(3): 229-48.

Murray, M. D., J. Young, et al. (2007). "Pharmacist intervention to improve medication adherence in heart failure: a randomized trial." Ann Intern Med 146(10): 714-25.

Ntiri, D. W. and M. Stewart (2009). "Transformative learning intervention: effect on functional health literacy and diabetes knowledge in older African Americans." Gerontol Geriatr Educ 30(2): 100-13.

Peters, E., N. Dieckmann, et al. (2007). "Less is more in presenting quality information to consumers." Med Care Res Rev 64(2): 169-90.

Roberts, N. J., Z. Mohamed, et al. (2009). "The development and comprehensibility of a pictorial asthma action plan." Patient Educ Couns 74(1): 12-8.

Robinson, L. D., Jr., D. P. Calmes, et al. (2008). "The impact of literacy enhancement on asthma-related outcomes among underserved children." J Natl Med Assoc 100(8): 892-6.

Rothman, R. L., D. A. DeWalt, et al. (2004). "Influence of patient literacy on the effectiveness of a primary care-based diabetes disease management program." Jama 292(14): 1711-6.

Rothman, R. L., R. Malone, et al. (2005). "The Spoken Knowledge in Low Literacy in Diabetes scale: a diabetes knowledge scale for vulnerable patients." Diabetes Educ 31(2): 215-24.

Rothman, R., R. Malone, et al. (2004). "The relationship between literacy and glycemic control in a diabetes disease-management program." Diabetes Educ 30(2): 263-73.

Rudd, R. E., D. C. Blanch, et al. (2009). "A randomized controlled trial of an intervention to reduce low literacy barriers in inflammatory arthritis management." Patient Educ Couns 75(3): 334-9.

Rutherford, J., R. Holman, et al. (2006). "Low literacy: a hidden problem in family planning clinics." J Fam Plann Reprod Health Care 32(4): 235-40.

Schapira, M. M., S. L. Davids, et al. (2004). "Agreement between scales in the measurement of breast cancer risk perceptions." Risk Anal 24(3): 665-73.

Schillinger, D., H. Hammer, et al. (2008). "Seeing in 3-D: examining the reach of diabetes self-management support strategies in a public health care system." Health Educ Behav 35(5): 664-82.

Schillinger, D., H. Hammer, et al. (2008). "Seeing in 3-D: examining the reach of diabetes self-management support strategies in a public health care system." Health education & behavior : the official publication of the Society for Public Health Education(5): 664-82.

Schillinger, D., M. Handley, et al. (2009). "Effects of self-management support on structure, process, and outcomes among vulnerable patients with diabetes: a three-arm practical clinical trial." Diabetes Care 32(4): 559-66.

Sheridan, S. L. and M. Pignone (2002). "Numeracy and the medical student's ability to interpret data." Eff Clin Pract 5(1): 35-40.

Sheridan, S. L., M. P. Pignone, et al. (2003). "A randomized comparison of patients' understanding of number needed to treat and other common risk reduction formats." J Gen Intern Med 18(11): 884-92.

Sudore, R. L., A. D. Schickedanz, et al. (2008). "Engagement in multiple steps of the advance care planning process: a descriptive study of diverse older adults." J Am Geriatr Soc 56(6): 1006-13.

Sudore, R. L., C. S. Landefeld, et al. (2006). "Use of a modified informed consent process among vulnerable patients: a descriptive study." J Gen Intern Med 21(8): 867-73.

Sudore, R. L., C. S. Landefeld, et al. (2007). "An advance directive redesigned to meet the literacy level of most adults: a randomized trial." Patient Educ Couns 69(1-3): 165-95.

van Servellen, G., A. Nyamathi, et al. (2005). "Effects of a treatment adherence enhancement program on health literacy, patient-provider relationships, and adherence to HAART among low-income HIV-positive Spanish-speaking Latinos." AIDS Patient Care STDS 19(11): 745-59.

von Wagner, C., C. Semmler, et al. (2009). "Health literacy and self-efficacy for participating in colorectal cancer screening: The role of information processing." Patient Educ Couns 75(3): 352-7.

Wallace, A. S., H. K. Seligman, et al. (2009). "Literacy-appropriate educational materials and brief counseling improve diabetes self-management." Patient Educ Couns 75(3): 328-33.

Weiss, B. D., L. Francis, et al. (2006). "Literacy education as treatment for depression in patients with limited literacy and depression: a randomized controlled trial." J Gen Intern Med 21(8): 823-8.

Yates, K. and A. Pena (2006). "Comprehension of discharge information for minor head injury: a randomised controlled trial in New Zealand." N Z Med J 119(1239): U2101.