Determinants of Attendance In a Primary Care-Based Parenting Intervention

Background & Purpose: Parenting interventions such as Child-Adult Relationship Enhancement in Primary Care (PriCARE) are effective in improving caregiver practices and reducing child behavior problems, yet their impact depends on successful implementation. Limited engagement and early dropout challenge adoption and fidelity/dosage, core implementation outcomes outlined by Proctor et al. (2011). Understanding which families face structural or contextual barriers to PriCARE is essential for equitable implementation. This study examines caregiver, child, and household determinants of adoption (attending ≥1 session) and fidelity/dosage (number of sessions attended) of PriCARE.

Methods: We conducted a secondary analysis of pooled data from five randomized trials (including one virtual delivery trial) and one pre-post study (n=761 caregivers). Logistic regression estimated predictors of adoption, and linear regression assessed predictors of intervention dosage, with robust variance estimation accounting for clustering. Child demographics, caregiver characteristics, and household context were conceptualized as feasibility determinants within an implementation outcomes framework following Proctor et al.’s taxonomy. Adoption was defined as attending ≥1 session, and dosage was defined as the number of sessions attended among enrolled caregivers.

Results: Across trials, 83% attended at least one session, mean 3.33 sessions (SD = 2.25). In adjusted models, virtual delivery was associated with higher odds of adoption compared with in-person delivery (OR = 1.94, 95% CI 1.15-3.29, p = .014), while winter enrollment was associated with lower odds of adoption compared with spring enrollment (OR = 0.54, 95% CI 0.34-0.87, p = .011). Larger family size was also associated with lower odds of adoption (OR = 0.84, 95% CI 0.71-1.00, p = .045). Compared with caregivers aged 18-29, older caregivers had higher dosage, while a larger number of children in the household was associated with lower dosage (β = -0.32 sessions per additional child, p < .001). Longer time from enrollment to intervention was also associated with lower dosage (β = -0.03 sessions per 10-days increase, p = .046). Other child or caregiver characteristics examined were not associated with adoption or dosage, indicating feasibility barriers independent of characteristics such as education and race/ethnicity.

Conclusion: This study identifies differential determinants of adoption and dose of a primary care-based parenting intervention, underscoring the importance of distinguishing between initial engagement and sustained participation as separate implementation outcomes. Virtual delivery substantially increased adoption, while season of enrollment and household size were also associated with variation in implementation outcomes. Sustained participation was primarily influenced by household demands, particularly larger family size. Delays between enrollment and intervention start were associated with lower dosage, indicating that timeliness affects sustained participation. These results suggest disparities in engagement are driven more by structural and contextual barriers than by caregiver or child characteristics alone. Findings highlight the need for phase-specific implementation strategies, combining access-enhancing approaches (e.g., virtual or hybrid delivery, seasonal planning) to support adoption with burden-reducing supports (e.g., flexible pacing, childcare, asynchronous components, timely start) to improve fidelity/dosage among families with greater caregiving demands. Tailoring implementation strategies to address these feasibility constraints is critical for achieving equitable population‑level impact of PriCARE in real‑world primary care settings.