displays the demographic characteristics of our sample, overall and by racial/ethnic group. By design, the racial/ethnic distribution of our sample differs considerably from that of the U.S. population. Our sample is slightly older than the U.S. population as a whole and the full Knowledge Networks panel, and more likely to be in the middle income group than the overall U.S. population (DeNavas-Walt, Proctor, and Smith 2008
; U.S. Census Bureau 2009a
; Knowledge Networks
; No Date b). At the same time, the distribution of our sample by gender, education, and area of residence looks similar to both the broader U.S. population and the full Knowledge Networks panel (U.S. Census Bureau 2009a
; U.S. Census Bureau
; No Date a; U.S. Census Bureau
No Date b). Racial/ethnic differences in these characteristics are similar to those in the general population.
Demographic Characteristics of Respondents by Race/Ethnicity
shows mean expectations regarding physician behavior by race/ethnicity. Average responses tend to fall near the middle of the scale (“some” to “most” doctors), regardless of respondent race/ethnicity. Mean responses range from an overall average of 2.21–2.78 for positive behaviors, and 2.06–2.40 for negative behaviors, where 1 corresponds to “no doctors at all” and 4 to “all doctors.” Notably, the only expectation for which there were statistically significant differences by race/ethnicity relates to whether physicians treat all patients fairly regardless of their race, with both African American (mean 2.53) and Latino (mean 2.78) respondents believing that fewer doctors do so than white respondents (mean 2.98), equivalent to 45 percent of African Americans and 20 percent of Latinos shifting responses from one category to an adjacent, more positive category. The remaining behaviors demonstrate no statistically significant racial/ethnic differences (p>.05 in all cases).
Expectations Regarding Physician Behavior by Race/Ethnicity
summarizes CAHPS responses to the vignettes (panel A) and the video of the simulated encounter (panel B). For each of the three CAHPS items, panel A shows the case-mix-adjusted mean response to each of the five written vignettes by race/ethnicity. Responses are increasingly positive with increasing depicted physician responsiveness to the patient. These findings are replicated in additional linear regressions (not shown), which found significant positive coefficients for physician responsiveness (β=0.56, 0.63, and 0.60 points per level of linearly coded responsiveness for listen, respect, and time, respectively; p<.001 for each), confirming that the written vignettes effectively conveyed the intended systematically increasing degree of physician responsiveness.
At the same time, however, responses are quite similar by race/ethnicity within a given vignette (p
>.05 in all instances). Case-mix-adjusted repeated-measures multivariate models that were designed to maximize statistical power to detect racial/ethnic differences confirmed this (not shown). In these same models, there was no significant association of African American or Latino race/ethnicity, as compared with white, with CAHPS responses (p
>.4 in all instances), suggesting that the three groups responded to the CAHPS reports items and used the response scales in similar ways when presented with identical written stimulus material. Given the absence of evident disparities here, additional analytic techniques applicable to these vignettes (King et al. 2004
) were not pursued.
Panel B of shows mean responses to the CAHPS questions that were asked of each respondent following the video viewing. Notably, the mean 0–10 rating of the doctor was below 5 for all racial/ethnic groups, suggesting that the physician in this third-person encounter was perceived more negatively than is typical of perceptions of one's own physician in the real world, given that means near 9 are more typical for such ratings of one's own physician (e.g., Elliott et al. 2009b
). Coefficients in case-mix-adjusted regressions showed no evidence of racial/ethnic differences in responses to any of the five modified Doctor Communication items or in responses to the global rating. A repeated-measures multiple regression (similar to the model used for responses to the vignettes), which attempted to maximize power to detect racial/ethnic differences by pooling across outcomes, also failed to find significant evidence of differences (p
>.05 in all instances).
In addition, while white, African American, and Latino respondents assigned similar adjusted mean 0–10 ratings (4.37, 4.62, and 4.56, respectively, p
>.05) to the doctor in the video, the standard deviations for African Americans (2.63) and Latinos (2.59) were significantly greater than for whites (2.19, p
<.05 in each case, by the Levene test). Similarly, African American and Latino respondents were more likely to use responses at both ends of the scale than white respondents. In particular, African Americans and Latinos were more likely than whites to use both the bottom two response options (14 and 12 percent versus 6 percent) and the top two response options (7 and 8 percent versus 3 percent); ORs=1.90–2.81, p
<.05 for all four contrasts from multinomial logistic regression. This reflects greater use of the extremes of the scales, or greater ERT, among African American and Latino respondents. This has also been observed in real-world CAHPS data, particularly for Latinos (Elliott et al. 2009b
). There was no corresponding evidence of differences in ERT for the more specific report items (data not shown).
With respect to the index of perceived positive physician behaviors in the video, mean responses fell between 2 (very little) and 3 (to some extent). Mean perceptions of positive behaviors did not differ significantly by race/ethnicity (2.62 for African American, 2.56 for Latino, and 2.52 for white respondents; p>.2 for each comparison versus white, not shown). Mean responses for perceptions of negative physician behaviors occurred somewhat more often, nearly corresponding to a value of 3 (to some extent). The mean frequency of negative behaviors perceived by African Americans (2.73) was significantly lower than that for whites (2.93; p=.01); Latinos (2.83) did not significantly differ from whites (p>.2). These patterns are also consistent with respondents generally perceiving the video interaction as having at least as many negative as positive behaviors.
Finally, includes the results of regressing the 0–10 CAHPS global rating of the physician on race/ethnicity, the positive and negative perception scales, and interactions between these. Because of the presence of interaction terms with race/ethnicity, the “positive behavior” and “negative behavior” coefficients estimate those coefficients within the reference group of non-Hispanic whites. As expected, perceptions of positive behavior were positively associated with the global ratings and perceptions of negative behaviors were negatively associated with this rating (p<.0001 for each). The magnitude of this coefficient was twice as large for positive perceptions as for negative perceptions, perhaps suggesting that the absence of positive perceptions may more strongly drive poor overall assessments of physicians than the presence of negative perceptions. Both the main effects of race/ethnicity and the interaction terms were nonsignificant, which is consistent with perceptions of physician behavior having a similar influence on 0–10 ratings of physicians across racial/ethnic groups. The nonsignificant interactions also suggest that the larger role of positive than negative perceptions is consistent across racial/ethnic groups.
Multivariate Regression Predicting Global Rating of Physician Quality from Race/Ethnicity and Positive and Negative Perceptions of Physician Behavior in the Video Interaction*