Can We Use Preventive Care Utilization To Estimate Population Health Literacy?

• Health literacy is the ability to obtain, process, and understand basic health information and services needed to make appropriate health decisions.1

• An estimated 47% of adults in the United States (90 million people) have limited health literacy.2 Limited health literacy is associated with poor health outcomes and an estimated $106 to $238 billion in health care spending each year.3

• Currently, there is no validated national health literacy surveillance tool in the literature. Existing tools measure components of health literacy such as numeracy, prose or functional health literacy in a clinical setting.5

• The Behavioral Risk Factor Surveillance System (BRFSS) is an annually administered national telephone survey that measures several social and health behaviors, demographics, and socioeconomic characteristics.6 The BRFSS could serve as an assessment tool through which individual and population health literacy is measured.4 However, at present it lacks a direct measure of health literacy, creating the need for a proxy variable to measure health literacy.

BACKGROUND

OBJECTIVE

FIGURES RESULTS

• 31% of the adult population did not have a routine checkup within the past year (1-2yrs: 14%; >2yrs: 17%)

• 18% did not have a primary care provider• 15% did not have any form of health coverage• 16% reported that they were in fair or poor health• 48% reported a history of 2+ chronic diseases3

• Adults whose most recent checkup was 1-2yrs ago had 8% higher odds of a history of 2+ chronic diseases but 22% lower odds of reporting fair or poor health compared to the reference group (<1yr), all else equal.

• Adults whose most recent checkup was >2yrs ago had 63% higher odds of a history of 2+ chronic diseases but 8% lower odds of reporting fair or poor health compared to the reference group (<1yr), all else equal.

DISCUSSION

• The data suggests that low preventive care utilization is associated with a history of poor health but good or better self-reported health status.

• Over three quarters of adults with a history of multiple chronic diseases reported that they were in good or better health.

• This counterintuitive finding might be partly attributed to adults with chronic diseases experiencing stable health at the time of survey administration.

• It is also possible that some respondents indicated a health status that was more desirable than how they truly felt (social desirability bias).

• Another consideration is that the question on health status is a cross-sectional assessment of respondents’ perceptions of their health, whereas the questions about chronic diseases objectively assess respondents’ health history.

• The observed relationship between low preventive care utilization and a history of poor health outcomes is consistent with the relationship between low health literacy and poor health outcomes in the literature.

• Surveillance is an important step towards improving health literacy and reducing health care spending attributable to limited health literacy.

• The Institute of Medicine recommendation to use the BRFSS or another national data set to measure and track trends in population health literacy should be explored on a trial or ongoing basis.5

ACKNOWLEDGEMENTSThanks to Professor Annie Gjelsvik, PhD d and John Fulton, PhD d, e for their assistance with the development of this project.

• To assess the ability of the BRFSS to measure adult health literacy by testing the association between preventive care utilization (a proxy variable associated with adequate health literacy) and poor health outcomes.

School of Public Health, Brown University, Providence, RIPublic Health Specialist, Safer Institute, Providence, RI

Larry O. Warner, MPH

Notes:a Health Status: Good / Very Good / Excellent vs. Fair / Poor.b Chronic Conditions: High blood pressure, high cholesterol, diabetes, heart disease, heart attack,

stroke, or asthma. c Covariates for both models: race, age, gender, education, income, health coverage, having a

primary care provider.d School of Public Health, Brown University, Providence, RI.e Rhode Island Department of Health, Providence, RI.

METHODS

• Design: Analysis of 2009 BRFSS data (n=425,414).• Analysis: Multivariable logistic regression of 1) self-

reported health status,a and 2) a history of two or more chronic conditions against length of time since last routine checkup as a measure of preventive care utilization.b,c

< HS Graduate HS Graduate Some College College Graduate0%

5%

10%

15%

20%

25%

30%

35%

40%

Figure 2. Distribution of highest education level completed, stratified by time since last routine

checkup.<1 Year 1-2 Years >2 Years

Highest education level completed

Perc

enta

ge o

f Str

atum

Self-Reported Health Status

0-1 ChronicConditions

2+ ChronicConditions Total

Good / Very Good / Excellent57%

91%43%

76%100%

84%

Fair / Poor28%

9%72%

24%100%

16%

Total52%

100%48%

100%100%

100%

Figure 5. Self-reported health status vs. number of chronic diseases.

< 1 year 1 - 2 years > 2 years0

0.2

0.4

0.6

0.8

1

1.2

10.78

0.92

Figure 3. Odds ratio of self-reported poor health sta-tus by time since last routine checkup.

Time since last routine checkup

Adju

sted

c O

dds R

atio

(95%

CI)

< 1 year 1 - 2 years > 2 years0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

1 1.08

1.63

Figure 4. Odds ratio of multiple chronic diseases by time since last routine checkup.

Time since last routine checkupAd

just

edc

Odd

s Rati

o (9

5% C

I)

REFERENCES1. Ratzan SC, Parker RM. Health literacy – Identification and Response. J Health Comm 2006;11(8):713-15.2. Berkman ND, DeWalt DA, Sheridan S, Lohr KN, Pignone MP. Literacy and Health Outcomes: A Systematic

Review of the Literature. J Gen Int Med 2004:19:12.3. Institute of Medicine. Promoting Health Literacy to Encourage Prevention and Wellness: Workshop Summary.

Washington, DC: The National Academies Press; 2011.4. Institute of Medicine. Health Literacy: A Prescription to End Confusion. Washington, DC: The National

Academies Press; 2004.5. Institute of Medicine. Measures of Health Literacy: Workshop Summary. Washington, DC: The National

Academies Press; 2009.6. Centers for Disease Control and Prevention. Behavioral Risk Factor Surveillance System Survey Data.

Atlanta, GA: U.S. Department of Health and Human Services; 2009.

<1 Year 1-2 Years >2 Years0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

68% 66% 69%

12%9% 6%

3%4% 3%

14% 17% 18%

3% 4% 4%

Figure 1. Distribution of time since last routine checkup, stratified by race/ethnicity.

Multi/OtherHispanicAsianBlackWhite

Perc

enta

ge o

f Str

atum