The quality of caregiving and the parent-child relationship is critical for early child development (ECD) and has been shown to be modifiable. This study evaluated an ECD project in Tanzania, assessing the effectiveness of radio messaging (RM) alone and a combined radio messaging/video job aids/ECD (RMV-ECD) intervention, using a two-arm pre-post design study, which enrolled a cohort of caregivers of children 0-24 months in four districts of Tabora region, following them for nine months. ECD radio messages were broadcast on popular stations at least 10 times/day reaching all study districts. In two districts, community health workers (CHW) trained in UNICEF's Care for Child Development package and used ECD videos in home- and facility-based sessions with caregivers. Five outcomes were used to assess the intervention effects: ECD knowledge, early stimulation, father engagement, responsive care, and environment safety. Additionally the effect of the training and video job aids on the quality of CHWs' counseling support was evaluated primarily using structured observation checklists of household visits and facility group counseling sessions with caregivers and their children. Qualitative data was collected from a subset of caregivers and CHW participating in the study to assess acceptability and other perceptions of the project.

Standardized interventions aimed at supporting child development are successful in a variety of cultural and socio-economic contexts, particularly in low to middle income countries. Integrated community and facility-based interventions can improve parenting behaviors. Mass media radio messaging campaigns can increase caregiver and community knowledge, and caregiver motivation to seek appropriate health care through reaching a broader audience such as family/household influencers such as fathers or grandparents.

Study design and setting:

This was a two-arm quasi-experimental pre-post evaluation study, comparing different 9-month intervention packages to establish their relative impact on parenting skills and environment among a cohort of caregivers of children under age three years in Tabora region, located in central-western Tanzania and home to a predominantly rural (87%) population. The study included four districts divided into two intervention groups. The first group (Kaliua, Uyui districts) was exposed to the minimal intervention package, composed of radio messaging (RM) only. The second group (Nzega, Igunga districts) was exposed to the Malezi II full intervention package, composed of radio messaging, the introduction of short video job aids primarily for community health worker (CHW) use, and the UNICEF Care for Childhood Development (CCD) program (RMV-ECD).

Sample and sampling procedures:

As the comprehensive program intervention was primarily delivered by CHW who were affiliated with health facilities, 31 health facilities were purposefully selected located in 29 administrative units called wards (6-8/district). From these wards, 75 National Bureau of Statistics census enumeration areas (EA) were randomly sampled proportional to population size. The study team aimed to enumerate all households in sampled EAs, listing potentially eligible households if there was a resident adult (>18 years) primary caregiver of a child aged 0-24 months who intended to remain in the same area for at least one year, and was willing to be home-visited by a CHW. From these listed households, only one caregiver per household was recruited. Caregivers who were not able to provide written informed consent due to a cognitive impairment or language barrier; or who were the primary caregiver of an index child with a congenital anomaly or other disability; or who worked as a CHW or medical provider, were excluded from the study.

The study team estimated that a completed sample size of 430 caregivers per intervention group would provide 90% power to detect a 15% difference between the RM and RMV-ECD intervention groups at endline, and >80% power to detect at least a 5% change in each t intervention group between baseline and endline, at a 5% significance level. Of 8880 households enumerated, 1248 caregivers were recruited into the study and interviewed at baseline (October-December 2019). Of these, 1051 were eligible for follow-up; 1004 (96%) were successfully traced and interviewed at endline (January-March 2021). Almost all (n=985; 98%) caregivers interviewed at endline remained the primary caregiver of the index child from baseline. Of the 19 caregivers whose index child had died or moved from the household, eight nominated an eligible "replacement" child under three years and 11 completed a partial interview skipping questions that were no longer applicable.

A cohort of 120 CHWs was also enrolled from the two intervention districts, who were assigned to caregiver-cohort enrolled households in the RMV-ECD arm.

Data collection and study variables Structured questionnaires were administered in a private place in or near the consenting caregiver's home in the national language (Swahili). Five outcome variables were defined reflecting caregiver knowledge, stimulation practices, father engagement, responsive care, and household environment risk. Continuous scores for each variable were dichotomized at the median for analysis. Some scores, where the number of items differed by age of the child (early stimulation) or sub-group (environment risk), were standardized to a 0-1 scale by dividing the raw score by the number of items. The quality of CHWs counseling support was evaluated using a structured evaluation checklist, targeting two home and two clinic observations for each CHW in each round; pre and post intervention. The checklist had 23 items across 6 dimensions; introduce, educate, ask, plan/problem solve, interact/encourage, and responsive care. Under the qualitative process evaluation, 25 in-depth interviews (IDI) were completed with caregivers enrolled in the cohort, and four focus group discussions (FGD) were held among those in the CHW cohort.

Households who had:

Inclusion Criteria:

• resident adult (>18 years) primary caregiver of a child aged 0-24 months, and had the
• intention to remain in the same area for at least one year,
• willingness to be home-visited by a Community Health Worker.

Exclusion Criteria:

• unable or unwilling to give informed consent

CHW eligibility criteria:

• assigned to a Malezi II study health facility/catchment community
• working as a Malezi II project CHW (i.e. attended Malezi (I or II) training, or capacitated for Malezi II project through on-job training and mentoring)
• able to understand and willing to provide consent