Development and validation of a Spanish diabetes-specific numeracy measure: DNT-15 Latino

Tools to Measure Health Literacy among Adult Hispanic Populations with Type 2 Diabetes Mellitus: A Review of the Literature

Health literacy (HL) is associated with short- and long-term health outcomes, and this is particularly relevant in Hispanics, who are disproportionally affected by lower HL. Hispanics have become the largest minority population in the United States. Also, Hispanics experience higher burdens of chronic diseases such as type 2 diabetes mellitus (T2DM) than non-Hispanic whites. Thus, effectively choosing culturally appropriate validated instruments that measure a marker found in health assessments should be a serious consideration. Using a systemized approach, we identified and reviewed 33 publications and found eight different HL and numeracy (separate or combined) instruments. We assessed the study designs and instrument structures to determine how HL was measured across these studies. We categorized the results into direct and indirect measurements of HL. The Test of Functional Health Literacy in Adults (TOFHLA) family of HL instruments was favored for direct measures of HL, while the Brief Health Literacy Screen (BHLS) instrument was favored for indirect measures. Despite identified trends in instruments used, more comprehensive measurement tools have been developed but not validated in Hispanic populations. In conclusion, further validation of more comprehensive HL instruments in adult Hispanic populations with T2DM could better assess HL levels and improve health promotion efforts.

A Systematic Review Exploring Acculturation and Type 2 Diabetes in Spanish-Speaking Populations

BACKGROUND

Acculturation to the United States has been previously studied in Spanish-speaking populations, but little is known about the potential relationship between acculturation and type 2 diabetes mellitus (T2DM).

OBJECTIVE

The purpose of this systematic review was to explore the relationship between acculturation and T2DM in Spanish-speaking populations in the United States.

METHODS

Selected studies collected from a review of literature were analyzed by population, ethnicity, acculturation scale, and significance.

RESULTS

Thirty-two eligible articles showed conflicting data between the effects of acculturation on T2DM.

CONCLUSION

Overall, studies yielded inconclusive results on the significance of the relationship between acculturation and diabetes in Spanish-speaking populations, which merit further investigation.

Ideal instruments used to measure health literacy related to medication use: A systematic review

BACKGROUND

Prior studies showed the association between inadequate health literacy (HL) and poor medication-related skills, while none of the published studies have reviewed and compared the existing instruments used to measure medication-related HL. This systematic review comprehensively summarizes the existing instruments that assess medication-related HL.

OBJECTIVES

To identify appropriate HL instruments related to medication use as screening tools for enhancing patients' ability to use medications correctly.

METHODS

This review retrieved medication-related HL instruments that were published between 2000 and 2019 from three databases (i.e., PubMed, Scopus, EMBASE) and by hand-searching. The PRISMA procedure was followed as well as the SURGE guideline to assess the quality of studies. Psychometric properties, HL dimensions, and types of medication information gleaned from the items in three types of HL instruments (i.e., general, disease-specific, medication-specific) were compared to identify appropriate medication-related HL instruments.

RESULT

Forty-eight instruments were identified from 44 studies, whereas 70.8% instruments were either disease- or medication-specific HL instruments. Most instruments with different sample sizes showed certain an extent of reliability and validity. The distributions of HL dimensions and types of medication information among the relevant items were varied across different types of instruments. The five instruments (named as the 16SQ, AKQ-CQ, DHLKI, AKT, and ChMLM) were identified as the most appropriate instruments for three types of medication-related HL, respectively. These appropriate instruments consistently covered items related to HL dimensions of literacy and comprehension and medication-related information regarding dosing, treatment indication, and side effects/precautions.

CONCLUSION

Of 48 identified instruments mainly derived from disease- or medication-specific studies, the five most appropriate medication-related HL instruments were identified to support clinicians in facilitating patients' correct medication use. Further confirmation to explore the usefulness among these instruments are needed.

Association of Health Literacy and Nutritional Status Assessment with Glycemic Control in Adults with Type 2 Diabetes Mellitus

While the role of medical and nutrition factors on glycemic control among adults with type 2 diabetes mellitus (T2DM) has been well-established, the association between health literacy (H.L.) and glycemic control is inconsistent. This study aims to determine the association of H.L. and nutritional status assessments with glycemic control in adults with type 2 diabetes mellitus. A total of 280 T2DM respondents (mean (SD) age = 49.7 (10.3) years, Glycated hemoglobin (HbA1c) = 9.9 (2.6) %, and Body Mass Index = 32.7 (15.1) kg/m²) were included in this study. A short-form Test of Functional Health Literacy in Adults (S-TOFHLA) assessed the H.L. levels. Nutritional status assessments included client history, glycemic control, anthropometric, and biochemical data. The mean (S.D.) H.L. score was 45.7 (24.6), with 56% of the respondents had inadequate H.L. Inadequate H.L. was more common among those females; housewives, low education, received oral antidiabetic therapy, and shorter diabetes duration. Respondents with inadequate H.L. were significantly older and had higher HbA1c than those with marginal and adequate H.L. Meanwhile, respondents with inadequate and marginal H.L. levels had significantly higher total cholesterol, LDL-cholesterol, and systolic blood pressure than the respondents with adequate H.L. Low H.L. scores, self-employment status, received dual antidiabetic therapy (insulin with oral agents), received insulin alone, and had higher fasting blood glucose explained about 21% of the total variation in HbA1c (adjusted R² = 0.21; p < 0.001). Respondents with inadequate H.L. had poor glycemic control. The H.L. scores, together with nutritional status assessments, were the factors that predicted poor glycemic control among adults with T2DM.

Tools to Measure Health Literacy among US African Americans and Hispanics/Latinos with Type 2 Diabetes: A Scoping Review of the Literature

OBJECTIVE

To provide an overview of the health literacy tools that have been validated in samples of African Americans and Hispanics/Latinos with type 2 diabetes, growing segments of the US population.

METHODS

Following PRISMA guidelines, three electronic databases were searched. The following inclusion criteria were used: peer-reviewed research; examined validity of a health literacy tool; and included US African American and/or Hispanic/Latino adults with type 2 diabetes.

RESULTS

Sixteen studies were selected; none exclusively included African Americans while 3 exclusively included Hispanics/Latinos in the sample. Seventeen health literacy tools were identified. Among African Americans, 2 health literacy screeners, 2 diabetes knowledge, and 3 numeracy tools have been validated. Among Hispanics/Latinos, 1 health literacy screener, 1 diabetes knowledge, and 1 numeracy tool have been validated. However, cross-cultural adaptation principles were rarely considered in the development and validation of these tools.

CONCLUSION

In those with type 2 diabetes, future studies should investigate the validity of health literacy screeners among English-speaking Hispanics/Latinos and general health literacy tools among African Americans and Hispanics/Latinos. Evidence on the validity of diabetes knowledge and numeracy tools was mixed across studies.

PRACTICE IMPLICATIONS

Findings can inform the selection of culturally-appropriate health literacy tools in clinical and research settings.

The Partnership to Improve Diabetes Education Trial: a Cluster Randomized Trial Addressing Health Communication in Diabetes Care

BACKGROUND

Effective type 2 diabetes care remains a challenge for patients including those receiving primary care in safety net settings.

OBJECTIVE

The Partnership to Improve Diabetes Education (PRIDE) trial team and leaders from a regional department of health evaluated approaches to improve care for vulnerable patients.

DESIGN

Cluster randomized controlled trial.

PATIENTS

Adults with uncontrolled type 2 diabetes seeking care across 10 unblinded, randomly assigned safety net clinics in Middle TN.

INTERVENTIONS

A literacy-sensitive, provider-focused, health communication intervention (PRIDE; 5 clinics) vs. standard diabetes education (5 clinics).

MAIN MEASURES

Participant-level primary outcome was glycemic control [A1c] at 12 months. Secondary outcomes included select health behaviors and psychosocial aspects of care at 12 and 24 months. Adjusted mixed effects regression models were used to examine the comparative effectiveness of each approach to care.

KEY RESULTS

Of 410 patients enrolled, 364 (89%) were included in analyses. Median age was 51 years; Black and Hispanic patients represented 18% and 25%; 96% were uninsured, and 82% had low annual income level (< $20,000); adequate health literacy was seen in 83%, but numeracy deficits were common. At 12 months, significant within-group treatment effects occurred from baseline for both PRIDE and control sites: adjusted A1c (- 0.76 [95% CI, - 1.08 to - 0.44]; P < .001 vs - 0.54 [95% CI, - 0.86 to - 0.21]; P = .001), odds of poor eating (0.53 [95% CI, 0.33-0.83]; P = .01 vs 0.42 [95% CI, 0.26-0.68]; P < .001), treatment satisfaction (3.93 [95% CI, 2.48-6.21]; P < .001 vs 3.04 [95% CI, 1.93-4.77]; P < .001), and self-efficacy (2.97 [95% CI, 1.89-4.67]; P < .001 vs 1.81 [95% CI, 1.1-2.84]; P = .01). No significant difference was observed between study arms in adjusted analyses.

CONCLUSIONS

Both interventions improved the participant's A1c and behavioral outcomes. PRIDE was not more effective than standard education. Further research may elucidate the added value of a focused health communication program in this setting.

The Role of Health Literacy in Diabetes Knowledge, Self-Care, and Glycemic Control: a Meta-analysis

BACKGROUND

Empirical evidence on how health literacy affects diabetes outcomes is inconsistent. The purpose of this meta-analysis was to quantitatively summarize the findings on the associations between health literacy and diabetes knowledge, self-care activities, and glycemic control as disease-related outcomes, with specific focus on the type of health literacy assessment.

DATA SOURCES

Nine databases (MEDLINE, CINAHL, Communication and Mass Media Complete, PsychInfo, PsychArticles, Psychology and Behavioral Sciences Collection, ERIC, Sociology, Embase) were searched for peer-reviewed original research articles published until 31 March 2018.

METHODS

Studies with type 1 and/or type 2 diabetes patients aged 18 or older, providing a calculable baseline effect size for functional health literacy and diabetes knowledge, self-care activities, or HbA1C were included.

RESULTS

The meta-analysis includes 61 studies with a total of 18,905 patients. The majority were conducted in the USA, on type 2 diabetes patients, and used the S-TOFHLA as a performance-based or the BHLS as a perception-based measure of functional health literacy. Meta-analytic results show that all three outcomes are related to health literacy. Diabetes knowledge was best predicted by performance-based health literacy measures, self-care by self-report measures, and glycemic control equally by both types of health literacy assessment.

DISCUSSION

Health literacy plays a substantial role in diabetes knowledge. Findings for the role of health literacy in self-care and glycemic control remain heterogeneous, partly due to the type of health literacy assessment (performance- vs. perception-based). This has implications for the use of health literacy measures in clinical settings and original research. This meta-analysis was limited to functional health literacy and, due to the paucity of studies, did not investigate the role of other dimensions including communicative and critical health literacy.

Associations of health literacy with diabetic foot outcomes: a systematic review and meta-analysis

BACKGROUND

People with diabetes have low health literacy, but the role of the latter in diabetic foot disease is unclear.

AIM

To determine, through a systematic review and meta-analysis, if health literacy is associated with diabetic foot disease, its risk factors, or foot care.

METHODS

We searched PubMed, EMBASE, CINAHL, Web of Science, Scopus and Science Direct. All studies were screened and data extracted by two independent reviewers. Studies in English with valid and reliable measures of health literacy and published tests of association were included. Data were extracted on the associations between the outcomes and health literacy. Meta-analyses were performed using random effects models.

RESULTS

Sixteen articles were included in the systematic review, with 11 in the meta-analysis. In people with inadequate health literacy, the odds of having diabetic foot disease were twice those in people with adequate health literacy, but this was not statistically significant [odds ratio 1.99 (95% CI 0.83, 4.78); two studies in 1278 participants]. There was no statistically significant difference in health literacy levels between people with and without peripheral neuropathy [standardized mean difference -0.14 (95% CI -0.47, 0.18); two studies in 399 participants]. There was no association between health literacy and foot care [correlation coefficient 0.01 (95% CI -0.07, 0.10); seven studies in 1033 participants].

CONCLUSIONS

There were insufficient data to exclude associations between health literacy and diabetic foot disease and its risk factors, but health literacy appears unlikely to have a role in foot care. The contribution of low health literacy to diabetic foot disease requires definitive assessment through robust longitudinal studies.

Type 2 Diabetes Self-management Among Spanish-Speaking Hispanic Immigrants

This article describes the quantitative findings of a mixed-methods study that examined the relationship among knowledge, self-efficacy, health promoting behaviors, and type 2 diabetes self-management among recent Spanish-speaking, limited English proficient immigrants to the US. This population is at risk for both a higher incidence of disease and increased barriers to successful disease management compared to the general US population. Distinguishing aspects of this study compared to the available literature are the comprehensive nature of the data collected, the theoretical component, and the analysis and modeling approach. Social cognitive theory provides the framework for the study design and analysis. An innovative community-based recruiting strategy was used, a broad range of physiological measures related to health were observed, and instruments related to knowledge, self-efficacy, and healthy lifestyle behaviors were administered orally in Spanish to 30 participants. A broad range of statistical analysis methods was applied to the data, including a set of three structural equation models. The study results are consistent with the importance of education, health knowledge, and healthy lifestyle practices for type 2 diabetes self-management. With the usual cautions associated with applying structural equation modeling to modest sample sizes, multiple elements of the posited theoretical model were consistent with the data collected. The results of the investigation of this under-studied population indicate that, on average, participants were not effectively managing their disease. The results suggest that clinical interventions focused on improving knowledge, nutrition, and physical activity, reducing stress, and leveraging the importance of interpersonal relations could be effective intervention strategies to improve self-management among this population.

Quick screen of patients' numeracy and document literacy skills: the factor structure of the Newest Vital Sign

INTRODUCTION

The Newest Vital Sign (NVS) is a survey designed to measure general health literacy whereby an interviewer asks six questions related to information printed on a nutritional label from an ice cream container. It enables researchers to evaluate several health literacy dimensions in a short period of time, including document literacy, comprehension, quantitative literacy (numeracy), application, and evaluation. No study has empirically examined which items belong to which latent dimensions of health literacy in the NVS using factor analysis. Identifying the factor structure of the NVS would enable health care providers to choose appropriate intervention strategies to address patients' health literacy as well as improve their health outcomes accordingly. This study aimed to explore the factor structure of the NVS that is used to assess multiple dimensions of health literacy.

METHODS

A cross-sectional study administering the NVS in a face-to-face manner was conducted at two family medicine clinics in the USA. One hundred and seventy four individuals who participated were at least 20 years old, diagnosed with type 2 diabetes, prescribed at least one oral diabetes medicine, and used English as their primary language. Exploratory factor analysis and confirmatory factor analysis were conducted to investigate the factor structure of the NVS.

RESULTS

Numeracy and document literacy are two dimensions of health literacy that were identified and accounted for 63.05% of the variance in the NVS. Internal consistency (Cronbach's alpha) of the NVS were 0.78 and 0.91 for numeracy and document literacy, respectively.

CONCLUSION

Numeracy and document literacy appropriately represent the factor structure of the NVS and may be used for assessing health literacy in greater detail for patients with type 2 diabetes.

Validation of a diabetes numeracy test in Arabic

Background

The prevalence of diabetes Mellitus in Saudi Arabia is 24%, ranking it among the top ten Worldwide. Diabetes education focuses on self-management and relies on numeracy skills. Poor numeracy may go unrecognized and it is important to have an assessment tool in Arabic to measure such a skill in diabetes care.

Objectives

To validate a 15-item Diabetes Numeracy Test (DNT-15) in the Arabic Language as a tool to assess the numeracy skills of patients with diabetes and to test its properties among Saudi patients with diabetes.

Methods

A 15-question Arabic-language test to assess diabetes numeracy among patients with diabetes on the basis of the diabetes numeracy test (DNT-15) was validated among a sample Arabic speaking Saudi patients with diabetes. Data collection included patients’ demographics, long-term glycemic control, diabetes type, duration, co-morbidities, and diabetes related knowledge questions. Internal reliability was assessed using Kuder-Richardson Formula 20 (KR-20).

Results

The average score of Arabic DNT-15 was 53.3% and took an average of 30 minutes to complete. The scores significantly correlated with education, income, HbA1c, and diabetes knowledge (p<0.05). Content Validity Ratio (CVR) of 0.75 and Content Validity Index (CVI) of 0.89 supported good content validity. The Arabic DNT-15 also had good internal reliability (KR20 = 0.90).

Conclusion

Patients with diabetes need numeracy skills to manage their disease. Level of education does not reflect level of numeracy, and low numeracy skills might be unnoticed by health care providers. The Arabic DNT-15 is a valid and reliable scale to identify Arabic speaking patients with difficulties in certain diabetes-related numeracy skills.

Validating Health Literacy and Numeracy Measures in Minority Groups

Background:

Validation studies of existing health literacy or numeracy tools among racial/ethnic minorities are limited.

Objective:

This study assessed the validity of the Subjective Numeracy Scale (SNS), the Diabetes Numeracy Test (DNT-5), the Brief Health Literacy Screen (BHLS), and the Short Test of Functional Health Literacy in Adults (S-TOFHLA) by trait (health literacy or numeracy) and by method (subjective or objective) among non-Hispanic white (NHW), non-Hispanic black (NHB), and Hispanic patients with type 2 diabetes mellitus (T2DM).

Methods:

We conducted a secondary analysis of baseline data from the Partnering to Improve Diabetes Education (PRIDE) study, a clustered randomized controlled trial testing the efficacy of a health communication intervention on T2DM outcomes at state Department of Health clinics in middle Tennessee. PRIDE participants with race/ethnicity data available (n = 398) were included in this study. Most patients identified as NHW (59%), 18% identified as NHB, and 23% identified as Hispanic. Pearson correlations among the 4 measures were compared for each racial/ethnic group by trait and method. The convergent validity of each measure with education was also assessed using Pearson correlation analyses.

Key Results:

Significant correlations were observed across all 3 subgroups for the numeracy measures (SNS and DNT-5) and the objective measures (DNT-5 and S-TOFHLA). Nonsignificant correlations were observed among Hispanic participants for the health literacy measures (BHLS and S-TOFHLA, correlation coefficient = 0.13) and among NHB and Hispanic participants for the subjective measures (SNS and BHLS, correlations coefficients = 0.15 and 0.09, respectively). A significant positive correlation was noted between education and each measure across all 3 subgroups.

Conclusions:

Subjective and health literacy measures demonstrate weaker correlations than objective and numeracy measures, respectively, among minority patients in this study. Our findings highlight the need to further evaluate the appropriateness of these tools for use with minority populations, particularly the BHLS for Hispanic patients. [Health Literacy Research and Practice. 2017;1(2):e23–e30.]

Plain Language Summary:

Few studies have tested the validity of health literacy and numeracy measures in minority groups. This study highlights racial/ethnic differences in the results of validity testing of the Subjective Numeracy Scale, the Diabetes Numeracy Test, the Brief Health Literacy Screen, and the Short Test of Functional Health Literacy in Adults among adults with type 2 diabetes.

Development and Validation of the Spanish Numeracy Understanding in Medicine Instrument

BACKGROUND

The Spanish-speaking population in the U.S. is large and growing and is known to have lower health literacy than the English-speaking population. Less is known about the health numeracy of this population due to a lack of health numeracy measures in Spanish.

OBJECTIVE

we aimed to develop and validate a short and easy to use measure of health numeracy for Spanish-speaking adults: the Spanish Numeracy Understanding in Medicine Instrument (Spanish-NUMi).

DESIGN

Items were generated based on qualitative studies in English- and Spanish-speaking adults and translated into Spanish using a group translation and consensus process. Candidate items for the Spanish NUMi were selected from an eight-item validated English Short NUMi. Differential Item Functioning (DIF) was conducted to evaluate equivalence between English and Spanish items. Cronbach's alpha was computed as a measure of reliability and a Pearson's correlation was used to evaluate the association between test scores and the Spanish Test of Functional Health Literacy (S-TOFHLA) and education level.

PARTICIPANTS

Two-hundred and thirty-two Spanish-speaking Chicago residents were included in the study.

KEY RESULTS

The study population was diverse in age, gender, and level of education and 70 % reported Mexico as their country of origin. Two items of the English eight-item Short NUMi demonstrated DIF and were dropped. The resulting six-item test had a Cronbach's alpha of 0.72, a range of difficulty using classical test statistics (percent correct: 0.48 to 0.86), and adequate discrimination (item-total score correlation: 0.34-0.49). Scores were positively correlated with print literacy as measured by the S- TOFHLA (r = 0.67; p < 0.001) and varied as predicted across grade level; mean scores for up to eighth grade, ninth through twelfth grade, and some college experience or more, respectively, were 2.48 (SD ± 1.64), 4.15 (SD ± 1.45), and 4.82 (SD ± 0.37).

CONCLUSIONS

The Spanish NUMi is a reliable and valid measure of important numerical concepts used in communicating health information.

State of the science of health literacy measures: Validity implications for minority populations

OBJECTIVES

To review the evidence supporting the validity of health literacy (HL) measures for ethnic minority populations.

METHODS

PubMed, CINAHL, and PsycINFO databases were searched for HL measures between 1965 and 2013.

RESULTS

A total of 109HL measures were identified; 37 were non-English HL measures and 72 were English language measures. Of the 72 English language measures, 17 did not specify the racial/ethnic characteristic of their sample. Of the remaining 55 measures, 10 (18%) did not include blacks, 30 (55%) did not include Hispanics, and 35 (64%) did not include Asians in their validation sample. When Hispanic and Asian Americans were included, they accounted for small percentages in the overall sample. Between 2005-2013, a growing number of REALM and TOFHLA translations were identified, and new HL measures for specific cultural/linguistic groups within and outside the United States were developed.

CONCLUSIONS

While there are a growing number of new and translated HL measures for minority populations, many existing HL measures have not been properly validated for minority groups.

PRACTICE IMPLICATIONS

HL measures that have not been properly validated for a given population should be piloted before wider use. In addition, improving HL instrument development/validation methods are imperative to increase the validity of these measures for minority populations.

Tools to measure health literacy among Spanish speakers: An integrative review of the literature

OBJECTIVE

Health literacy measurement can help inform healthcare service delivery. The objective of this study is to identify validated tools to measure health literacy among Spanish speakers and to summarize characteristics that are relevant when selecting tools for use in clinical or research settings.

METHODS

An English and Spanish search of 9 databases was conducted between October 2014 and May 2015. Inclusion criteria were peer-reviewed articles presenting initial validation and psychometric properties of a tool to measure health literacy among Spanish speaking patients. Characteristics relevant to tool selection were reviewed and presented.

RESULTS

Twenty articles validating 19 instruments met inclusion criteria. Instruments were designed for use with Spanish speakers in numerous contexts and measured different health literacy skills such as reading comprehension or numeracy. Methods used to validate tools were inconsistent across instruments.

CONCLUSION

Although tools have inconsistencies and inefficiencies, many can be used for assessment of health literacy among Spanish speakers.

PRACTICE IMPLICATIONS

Healthcare providers, organizations, and researchers can use this review to select effective health literacy tools to indicate patient's ability to understand and use health information so that services and materials can be more appropriately tailored to Spanish speaking patients.

Health communication, self-care, and treatment satisfaction among low-income diabetes patients in a public health setting

OBJECTIVE

Diabetes patients with limited resources often experience suboptimal care. Less is known about the role of effective health communication (HC) in caring for low income diabetes patients.

METHODS

Ten health department clinics in TN participated in a trial evaluating a literacy-sensitive communication intervention. We assessed the quality of baseline HC and measured associations with diabetes outcomes. Assessments included: demographics, measures of HC, health literacy, self-care behaviors, self-efficacy, medication non-adherence, treatment satisfaction, and A1C. Unadjusted and adjusted multivariable regression models were used to test associations.

RESULTS

Participants (N=411) were 49.7±9.5 years, 61% female, uninsured (96%), with A1C 9.6±2.1. In unadjusted analyses, better communication, was associated with lower medication non-adherence (OR 0.40-0.68, all p<0.05), higher treatment satisfaction (OR 1.76-1.96, all p<0.01), portion size reduction (OR 1.43, p<0.05), diabetes self-efficacy (OR 1.41, p<0.05), and lower A1C (β=-0.06, p<0.01). In adjusted analyses, communication quality remained associated with lower medication non-adherence (AOR 0.39-0.68, all p<0.05), and higher treatment satisfaction (AOR 1.90-2.21, all p<0.001).

CONCLUSIONS

Better communication between low-income patients and providers was independently associated with lower medication non-adherence and higher treatment satisfaction.

PRACTICE IMPLICATIONS

Communication quality may be an important modifiable approach to improving diabetes care for vulnerable populations.

Update on health literacy and diabetes

PURPOSE

Inadequate literacy is common among patients with diabetes and may lead to adverse outcomes. The authors reviewed the relationship between literacy and health outcomes in patients with diabetes and potential interventions to improve outcomes.

METHODS

We reviewed 79 articles covering 3 key domains: (1) evaluation of screening tools to identify inadequate literacy and numeracy, (2) the relationships of a range of diabetes-related health outcomes with literacy and numeracy, and (3) interventions to reduce literacy-related differences in health outcomes.

RESULTS

Several screening tools are available to assess patients' print literacy and numeracy skills, some specifically addressing diabetes. Literacy and numeracy are consistently associated with diabetes-related knowledge. Some studies suggest literacy and numeracy are associated with intermediate outcomes, including self-efficacy, communication, and self-care (including adherence), but the relationship between literacy and glycemic control is mixed. Few studies have assessed more distal health outcomes, including diabetes-related complications, health care utilization, safety, or quality of life, but available studies suggest low literacy may be associated with increased risk of complications, including hypoglycemia. Several interventions appear to be effective in improving diabetes-related outcomes regardless of literacy status, but it is unclear if these interventions can reduce literacy-related differences in outcomes.

CONCLUSIONS

Low literacy is associated with less diabetes-related knowledge and may be related to other important health outcomes. Further studies are needed to better elucidate pathways by which literacy skills affect health outcomes. Promising interventions are available to improve diabetes outcomes for patients with low literacy; more research is needed to determine their effectiveness outside of research settings.

Health literacy in Korean immigrants at risk for type 2 diabetes

Rising incidence of type 2 diabetes (DM) in Korean immigrants has highlighted the need for better prevention efforts. Health literacy is an important predictor in the utilization of preventative health measures, however little is known about health literacy in Korean immigrants. This study examined DM risk factors in a sample of 145 at-risk Korean immigrants, their level of health literacy, and associations between health literacy and DM risk factors. Findings indicated a high prevalence of DM risk factors and a low level of health literacy in the sample. Health literacy was correlated with English proficiency, acculturation, and lower waist to hip ratios among all participants, and with lower blood glucose levels among highly acculturated participants. Korean immigrants who are less acculturated may have lower health literacy than those who are more acculturated. Thus, linguistically and culturally sensitive health education should be incorporated into diabetes prevention efforts.

Glycemic control in young children with diabetes: the role of parental health literacy

OBJECTIVE

This cross sectional study examined the relationship between parental health literacy (HL), diabetes related numeracy, and parental perceived diabetes self-efficacy on glycemic control in a sample of young children with Type 1 DM.

METHODS

Seventy primary caregivers of children (age 3-9 years) with Type 1 DM were recruited and surveyed at diabetes outpatient clinic visits. Patients' medical histories were obtained by medical chart review.

RESULTS

Parental diabetes related numeracy (r=-.52, p<01), but not reading skills (r=-.25, p=NS) were inversely correlated with the child's glycemic control (HbA1c). Parental perceived diabetes self-efficacy was also negatively correlated to their child's HbA1c (r=-.47, p<01). When numeracy and parental perceived diabetes self-efficacy were included as predictors of HbA1c, the model was significant (F=12.93, p<.01) with both numeracy (β=-.46, p<.01) and parental perceived diabetes self-efficacy (β=-.36, p=.01) as significant predictors of HbA1c.

CONCLUSIONS

Data from this study highlight the importance of considering the role of parental numeracy, in health outcomes for children with Type 1 DM.

PRACTICE IMPLICATIONS

Practitioners should assess parental health literacy and consider intervention when needed.

A health literate approach to the prevention of childhood overweight and obesity

OBJECTIVE

To describe a systematic assessment of patient educational materials for the Growing Right Onto Wellness (GROW) trial, a childhood obesity prevention study targeting a low health literate population.

METHODS

Process included: (1) expert review of educational content, (2) assessment of the quality of materials including use of the Suitability Assessment of Materials (SAM) tool, and (3) material review and revision with target population.

RESULTS

12 core modules were developed and assessed in an iterative process. Average readability was at the 6th grade reading level (SMOG Index 5.63 ± 0.76, and Fry graph 6.0 ± 0.85). SAM evaluation resulted in adjustments to literacy demand, layout & typography, and learning stimulation & motivation. Cognitive interviews with target population revealed additional changes incorporated to enhance participant's perception of acceptability and feasibility for behavior change.

CONCLUSION

The GROW modules are a collection of evidence-based materials appropriate for parents with low health literacy and their preschool aged children, that target the prevention of childhood overweight/obesity.

PRACTICE IMPLICATIONS

Most trials addressing the treatment or prevention of childhood obesity use written materials. Due to the ubiquitous prevalence of limited health literacy, our described methods may assist researchers in ensuring their content is both understood and actionable.

Health literacy, physician trust, and diabetes-related self-care activities in Hispanics with limited resources

BACKGROUND

Hispanics with diabetes often have deficits in health literacy (HL). We examined the association among HL, psychosocial factors, and diabetes-related self-care activities.

METHODS

Cross-sectional analysis of 149 patients. Data included patient demographics and validated measures of HL, physician trust, self-efficacy, acculturation, self-care behaviors, and A1c.

RESULTS

Participants (N=60) with limited HL were older and less educated, and had more years with diabetes compared with adequate HL participants (N=89). Limited HL participants reported greater trust in their physician, greater self-efficacy, and better diet, foot care, and medication adherence. Health literacy status was not associated with acculturation or A1c. In adjusted analyses, HL status remained associated with physician trust, and we observed a notable but nonsignificant trend between HL status and medication adherence.

DISCUSSION

Lower HL was associated with greater physician trust and better medication adherence. Further research is warranted to clarify the role of HL and physician trust in optimizing self-care for Hispanics.

Health literacy and health outcomes in diabetes: a systematic review

BACKGROUND

Low health literacy is considered a potential barrier to improving health outcomes in people with diabetes and other chronic conditions, although the evidence has not been previously systematically reviewed.

OBJECTIVE

To identify, appraise, and synthesize research evidence on the relationships between health literacy (functional, interactive, and critical) or numeracy and health outcomes (i.e., knowledge, behavioral and clinical) in people with diabetes.

METHODS

English-language articles that addressed the relationship between health literacy or numeracy and at least one health outcome in people with diabetes were identified by two reviewers through searching six scientific databases, and hand-searching journals and reference lists.

FINDINGS

Seven hundred twenty-three citations were identified and screened, 196 were considered, and 34 publications reporting data from 24 studies met the inclusion criteria and were included in this review. Consistent and sufficient evidence showed a positive association between health literacy and diabetes knowledge (eight studies). There was a lack of consistent evidence on the relationship between health literacy or numeracy and clinical outcomes, e.g., A1C (13 studies), self-reported complications (two studies), and achievement of clinical goals (one study); behavioral outcomes, e.g., self-monitoring of blood glucose (one study), self-efficacy (five studies); or patient-provider interactions (i.e., patient-physician communication, information exchange, decision-making, and trust), and other outcomes. The majority of the studies were from US primary care setting (87.5 %), and there were no randomized or other trials to improve health literacy.

CONCLUSIONS

Low health literacy is consistently associated with poorer diabetes knowledge. However, there is little sufficient or consistent evidence suggesting that it is independently associated with processes or outcomes of diabetes-related care. Based on these findings, it may be premature to routinely screen for low health literacy as a means for improving diabetes-related health-related outcomes.

Measuring health literacy in individuals with diabetes: a systematic review and evaluation of available measures

OBJECTIVE

To identify instruments used to measure health literacy and numeracy in people with diabetes; evaluate their use, measurement scope, and properties; discuss their strengths and weaknesses; and propose the most useful, reliable, and applicable measure for use in research and practice settings.

METHODS

A systematic literature review was conducted to identify the instruments. Nutbeam's domains of health literacy and a diabetes health literacy skill set were used to evaluate the measurement scope of the identified instruments and to evaluate their applicability in people with diabetes.

RESULTS

Fifty-six studies were included, from which one diabetes-specific (LAD) and eight generic measures of health literacy (REALM, REALM-R, TOFHLA, s-TOFHLA, NVS, 3-brief SQ, 3-level HL Scale, SILS) and one diabetes-specific (DNT) and two generic measures of numeracy (SNS, WRAT) were identified. These instruments were categorized into direct measures, that is, instruments that assess the performance of individuals on health literacy skills and indirect measures that rely on self-report of these skills. The most commonly used instruments measure selective domains of health literacy, focus mainly on reading and writing skills, and do not address other important skills such as verbal communication, health care system navigation, health-related decision making, and numeracy. The structure, mode, and length of administration and measurement properties were found to affect the applicability of these instruments in clinical and research settings. Indirect self- or clinician-administered measures are the most useful in both clinical and research settings.

CONCLUSION

This review provides an evaluation of available health literacy measures and guidance to practitioners and researchers for selecting the appropriate measures for use in clinical settings and research applications.