Results From Probit Regression Models Used to Examine the Mediation Effect of Health Literacy on Disparities in Selected Health Outcomes Related to Race/Ethnicity and Educational Attainment (Model A = Without Health Literacy, Model B = With Health Literacy)
| Self-Rated Health Status β (SE) | Influenza Vaccination β (SE) | Mammogram β (SE) | Dental Checkup β (SE) | |||||
|---|---|---|---|---|---|---|---|---|
| Variable | A | B | A | B | A | B | A | B |
| MML=marginal maximum likelihood. | ||||||||
| Note: Standard errors are in parentheses. Three decimal places were kept when reporting standard error estimates of age. The small estimates were due to a much larger unit of age compared with other independent variables. Model A has self-rated health status or utilization of each of the preventive health services as the dependent variable, race/ethnicity and educational attainment as the independent variable, and 4 demographic variables as covariates. Model B adds health literacy as an independent variable. | ||||||||
| Source: Data used are from the 2003 National Assessment of Adult Literacy, conducted by the National Center for Education Statistics, Institute of Education Sciences, US Department of Education. | ||||||||
| a Statistically significant regression coefficients in each model at the α level of .05. | ||||||||
| b In the MML probit model, health literacy was measured on the item response theory (IRT) 𝛉 scale, typically ranging from −3 to 3. | ||||||||
| c Sex is not included in the probit model for mammogram. | ||||||||
| Race/ethnicity | ||||||||
| White | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Black | −0.34a (0.11) | −0.24a (0.04) | −0.24a (0.10) | −0.18a (0.04) | 0.23 (0.15) | 0.28a (0.06) | −0.13 (0.11) | −0.04 (0.04) |
| Latino/Hispanic | 0.02 (0.14) | 0.21a (0.07) | −0.04 (0.16) | 0.08 (0.07) | 0.57a (0.19) | 0.70a (0.07) | 0.19 (0.14) | 0.35a (0.05) |
| Other | −0.11 (0.30) | −0.09 (0.10) | 0.22 (0.19) | 0.24a (0.08) | −0.01 (0.25) | 0.02 (0.09) | −0.21 (0.32) | −0.20 (0.12) |
| Education | ||||||||
| >High school | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| High school or equivalency | −0.17 (0.11) | −0.08 (0.05) | −0.08 (0.10) | −0.03 (0.04) | −0.40a (0.14) | −0.36a (0.06) | −0.39a (0.10) | −0.31a (0.04) |
| <High school | −0.56a (0.12) | −0.36a (0.05) | −0.31a (0.11) | −0.18a (0.05) | −0.60a (0.13) | −0.46a (0.06) | −0.97a (0.12) | −0.80a (0.05) |
| Health literacyb | – | 0.23a (0.03) | – | 0.14a (0.02) | – | 0.17a (0.04) | – | 0.20a (0.03) |
| Age | −0.02a (0.006) | −0.01a (0.003) | 0.03a (0.006) | 0.03a (0.003) | −0.01 (0.007) | −0.006 (0.003) | 0.008 (0.005) | 0.02a (0.002) |
| Sexc | ||||||||
| Male | Ref | Ref | Ref | Ref | – | – | Ref | Ref |
| Female | 0.19a (0.08) | 0.15a (0.03) | 0.04 (0.08) | 0.01 (0.03) | – | – | 0.12 (0.08) | 0.07a (0.03) |
| Income | ||||||||
| >175% of poverty level | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| 100%–175% poverty level | −0.39a (0.11) | −0.32a (0.04) | −0.07 (0.10) | −0.03 (0.04) | −0.23 (0.12) | −0.18a (0.05) | −0.55a (0.10) | −0.49a (0.04) |
| <Poverty level | −0.62a (0.11) | −0.50a (0.05) | −0.23a (0.10) | −0.16a (0.05) | −0.14 (0.13) | 0.04 (0.05) | −0.54a (0.13) | −0.43a (0.06) |
| Nativity | ||||||||
| US born | Ref | Ref | Ref | Ref | Ref | Ref | Ref | Ref |
| Foreign born | −0.03 (0.17) | 0.10 (0.07) | −0.24 (0.13) | −0.16a (0.05) | −0.12 (0.22) | 0.04 (0.10) | 0.18 (0.15) | 0.30a (0.06) |
| Constant | 2.34a (0.50) | 1.77a (0.22) | −1.13a (0.45) | −1.52a (0.19) | 1.77a (0.52) | 1.32a (0.25) | 0.22 (0.35) | −0.33a (0.16) |