Poster #92 - Direct and Indirect Effects of Multiple Risk Factors on Vocabulary Development of Low-Income Toddlers

• In Event: 3-003 - Poster Session 09
  In Poster Session: PS 09 Section - Family Context & Processes

Integrative Statement

Introduction: Children growing up in low-income families experience heightened risk of language delays from accumulated risks that include maternal emotional distress and impoverished home environments (Claessens et al., 2015; Payne et al., 1994; Sameroff et al., 1998). The current study examined direct and indirect effects of multiple risk factors on vocabulary development, using data from the control group of the EHSRE Project (Love et al., 2005).

Methods: The sample comprised toddlers from low-income families who had critical variables at age 14 months (m) (N=782, 51.4% male). Maternal education was reported as <12 years (45.1%), 12 years / high school equivalency (29.8%), >12 years (25.1%). Assessments at 14m were: Parental Stress Index (Abidin, 1995), HOME Inventory (Bradley & Caldwell, 1984), Bayley Mental Development Index (MDI; Bayley, 1993), and MacArthur-Bates Communicative Development Inventories (CDI; Fenson et al., 1991). At 36m, a subsample (N=469) had scores on the Peabody Picture Vocabulary Test (PPVT; Dunn & Dunn, 1997). Delays in vocabulary comprehension were not evident at 14m (only 5.8% scored below the 10th percentile on the CDI), but emerged at 36m (52.7% scored <85 on the PPVT, where the expected value is 15.7% [population norms μ = 100, σ = 15]; M = 82.9, SD = 16.1).

Results: We used regression models to evaluate the impact of risk factors on vocabulary development, controlling for child cognition (MDI scores at 14m); see Table 1. HOME scores and gender (favoring girls) were the strongest predictors of CDI scores. Maternal distress was negatively associated with vocabulary production and early gestures, but not vocabulary comprehension. Maternal education was related to early gestures, but in the unexpected direction.
Maternal education and the HOME environment were the only significant predictors of vocabulary comprehension at 36m (PPVT scores), after controlling for prior language and cognitive ability (CDI and MDI scores at 14m). To assess cumulative risk, we tested for an indirect effect of maternal distress on vocabulary comprehension at 36m, mediated by the home environment, see Figure 1. Maternal distress was significant in predicting HOME scores, Z = –6.02, p< .001, β = –.27, CI –.35 :: –.19, and had a significant indirect effect on PPVT scores, Z = –2.52, p = .001, β = –.05, CI –.07 :: –.02. Other effects in the model were unchanged.

Discussion: These findings indicate the persistent impact of poor quality home environments and maternal emotional distress on vocabulary development over the first 3 years, with low maternal educational attainment later emerging as an additional risk factor. Higher levels of emotional distress have been shown to disrupt parental responsiveness and contribute to dysfunctional parent-child interactions (Elgar et al., 2007; Munson et al., 2001) as well as increased incidence of externalizing problems and decreased self-regulation in children (Choe et al., 2013; 2014). The evidence of cumulative risk on vocabulary development indicates the need for policies and programs to reduce maternal distress and improve the home environments of young children growing up in poverty for the sake of their future academic success (Morgan et al., 2015).

Authors

• Teresa Ober, The Graduate Center CUNY
  Presenting Author

• Patricia J. Brooks, College of Staten Island and The Graduate Center CUNY
  Non-Presenting Author