Different Responses to Social Capital Among Black People and White People: What Racial Differential Item Functioning Reveals for Racial Health Equity

Social capital has been conceptualized as features of social organization, such as networks, and norms that facilitate coordination and cooperation for mutual benefit. Because of long-standing anti-Black structural oppression in the United States, social capital may be associated with health differently for Black people than for other racial/ethnic groups. Our aim was to examine the psychometric properties of social capital indicators, comparing responses from Black and White people to identify whether there is differential item functioning (DIF) in social capital according to race. DIF examines how items are related to a latent construct and whether this relationship differs across groups such as different racial groups. We used data from respondents to the Southeastern Pennsylvania Household Health Survey in 2004, who lived in Philadelphia (n = 2,048), a city with a large Black population. We used item response theory analysis to test for racial DIF. We found DIF across the items, indicating measurement error, which could be related to the way these items were developed (i.e., based on cultural assumptions tested in mainstream White America). Hence, our findings underscore the need to interrogate the assumptions that underly existing social capital items through an equity-based lens, and to take corrective action when developing new items to ensure that they are racially and culturally congruent.