The meaning of numbers in health: exploring health numeracy in a Mexican-American population.

BACKGROUND: Health numeracy can be defined as the ability to use numeric information in the context of health. The interpretation and application of numbers in health may vary across cultural groups. OBJECTIVE: To explore the construct of health numeracy among persons who identify as Mexican American. DESIGN: Qualitative focus group study. Groups were stratified by preferred language and level of education. Audio-recordings were transcribed and Spanish groups (n = 3) translated to English. An analysis was conducted using principles of grounded theory. PARTICIPANTS: A purposeful sample of participants from clinical and community sites in the Milwaukee and Chicago metropolitan areas. MAIN MEASURES: A theoretical framework of health numeracy was developed based upon categories and major themes that emerged from the analysis. KEY RESULTS: Six focus groups were conducted with 50 participants. Initial agreement in coding was 59-67% with 100% reached after reconciliation by the coding team. Three major themes emerged: 1) numeracy skills are applied to a broad range of communication and decision making tasks in health, 2) affective and cognitive responses to numeric information influence use of numbers in the health setting, and 3) there exists a strong desire to understand the meaning behind numbers used in health. The findings informed a theoretical framework of health numeracy. CONCLUSIONS: Numbers are important across a range of skills and applications in health in a sample of an urban Mexican-American population. This study expands previous work that strives to understand the application of numeric skills to medical decision making and health behaviors.

Changes in research on language barriers in health care since 2003: A cross-sectional review study.

BACKGROUND: Understanding how to mitigate language barriers is becoming increasingly important for health care providers around the world. Language barriers adversely affect patients in their access to health services; comprehension and adherence; quality of care; and patient and provider satisfaction. In 2003, the United States (US) government made a major change in national policy guidance that significantly affected limited English proficient patients' ability to access language services. OBJECTIVE: The objectives of this paper are to describe the state of the language barriers literature inside and outside the US since 2003 and to compare the research that was conducted before and after a national policy change occurred in the US. We hypothesize that language barrier research would increase inside and outside the US but that the increase in research would be larger inside the US in response to this national policy change. METHODS: We reviewed the research literature on language barriers in health care and conducted a cross sectional analysis by tabulating frequencies for geographic location, language group, methodology, research focus and specialty and compared the literature before and after 2003. RESULTS: Our sample included 136 studies prior to 2003 and 426 studies from 2003 to 2010. In the 2003-2010 time period there was a new interest in studying the providers' perspective instead of or in addition to the patients' perspective. The methods remained similar between periods with greater than 60% of studies being descriptive and 12% being interventions. CONCLUSIONS: There was an increase in research on language barriers inside and outside the US and we believe this was larger due to the change in the national policy. We suggest that researchers worldwide should move away from simply documenting the existence of language barriers and should begin to focus their research on documenting how language concordant care influences patient outcomes, providing evidence for interventions that mitigate language barriers, and evaluating the cost effectiveness of providing language concordant care to patients with language barriers. We think this is possible if funding agencies around the world begin to request proposals for these types of research studies. Together, we can begin document meaningful ways to provide high quality health care to patients with language barriers.

The numeracy understanding in medicine instrument: a measure of health numeracy developed using item response theory.

BACKGROUND: Health numeracy can be defined as the ability to understand and apply information conveyed with numbers, tables and graphs, probabilities, and statistics to effectively communicate with health care providers, take care of one's health, and participate in medical decisions. OBJECTIVE: To develop the Numeracy Understanding in Medicine Instrument (NUMi) using item response theory scaling methods. DESIGN: A 20-item test was formed drawing from an item bank of numeracy questions. Items were calibrated using responses from 1000 participants and a 2-parameter item response theory model. Construct validity was assessed by comparing scores on the NUMi to established measures of print and numeric health literacy, mathematic achievement, and cognitive aptitude. PARTICIPANTS: Community and clinical populations in the Milwaukee and Chicago metropolitan areas. RESULTS: Twenty-nine percent of the 1000 respondents were Hispanic, 24% were non-Hispanic white, and 42% were non-Hispanic black. Forty-one percent had no more than a high school education. The mean score on the NUMi was 13.2 (s = 4.6) with a Cronbach α of 0.86. Difficulty and discrimination item response theory parameters of the 20 items ranged from -1.70 to 1.45 and 0.39 to 1.98, respectively. Performance on the NUMi was strongly correlated with the Wide Range Achievement Test-Arithmetic (0.73, P < 0.001), the Lipkus Expanded Numeracy Scale (0.69, P < 0.001), the Medical Data Interpretation Test (0.75, P < 0.001), and the Wonderlic Cognitive Ability Test (0.82, P < 0.001). Performance was moderately correlated to the Short Test of Functional Health Literacy (0.43, P < 0.001). LIMITATIONS: The NUMi was found to be most discriminating among respondents with a lower-than-average level of health numeracy. CONCLUSIONS: The NUMi can be applied in research and clinical settings as a robust measure of the health numeracy construct.