Data from: Two-year impact of community-based health screening and parenting groups on child development in Zambia: follow-up to a cluster-randomized controlled trial

Background: Early childhood interventions have potential to offset the
negative impact of early adversity. We evaluated the impact of a
community-based parenting group intervention on child development in
Zambia. Methods and Findings: We conducted a non-masked cluster-randomized
controlled trial in Southern Province, Zambia. Thirty clusters of villages
were matched based on population density and distance from the nearest
health center, and randomly assigned to intervention (15 clusters, 268
caregiver-child dyads) or control (15 clusters, 258 caregiver-child
dyads). Caregivers were eligible if they had a child six to 12 months old
at baseline. In intervention clusters, caregivers were visited twice per
month during the first year of the study by Child Development Agents
(CDAs) and were invited to attend fortnightly parenting group meetings.
Parenting groups selected 'head mothers' from their communities
who were trained by CDAs to facilitate meetings and deliver a diverse
parenting curriculum. The parenting group intervention, originally
designed to run for one year, was extended and households were visited for
a follow-up assessment at the end of year two. The control group did not
receive any intervention. Intention-to-treat analysis was performed for
primary outcomes measured at the year two follow-up: stunting and five
domains of neurocognitive development measured using the Bayley Scale for
Infant and Toddler Development (BSID-III). In order to show Cohen's d
estimates, BSID-III composite scores were converted to z-scores by
standardizing within the study population. 195/268 children (73%) in the
intervention and 182/258 children (71%) in the control group were assessed
at endline after two years. The intervention significantly reduced
stunting (56/195 vs. 72/182; adjusted OR 0.45, 95% CI 0.22 to 0.92;
p=0.028) and had a significant positive impact on language (β 0.14, 95% CI
0.01 to 0.27; p=0.039). The intervention did not significantly impact
cognition (β 0.11, 95% CI -0.06 to 0.29; p=0.196), motor (β -0.01, 95% CI
-0.25 to 0.24; p=0.964), adaptive behavior (β 0.21, 95% CI -0.03 to 0.44;
p=0.088), or social-emotional development (β 0.20, 95% CI -0.04 to 0.44;
p=0.098). Observed impacts may have been due in part to home visits by
CDAs during the first year of the intervention. Conclusions: The results
of this trial suggest that parenting groups hold promise for improving
child development, particularly physical growth, in low-resource settings
like Zambia. This study is registered at ClinicalTrials.gov (NCT02234726).