Scalable Accountability for Last-Mile Child Health Service Delivery: A Cluster-Randomized Trial of Dimagi's Connect Child Health Campaign in Nigeria

Last registered on September 28, 2026

Pre-Trial

General Information

Title

RCT ID

AEARCTR-0019508

Initial registration date

September 28, 2026

Initial registration date is when the trial was registered.

It corresponds to when the registration was submitted to the Registry to be reviewed for publication.

First published

September 28, 2026, 10:00 AM EDT

First published corresponds to when the trial was first made public on the Registry after being reviewed.

Locations

Country

Nigeria

Region

Kaduna, Kano, Jigawa, and Gombe states, northern Nigeria

Primary Investigator

Name

Doug Parkerson

Affiliation

Innovations for Poverty Action

Contact Primary Investigator

Other Primary Investigator(s)

Additional Trial Information

Status

On going

Start date

2026-06-01

End date

2027-05-31

Keywords

Health

Additional Keywords

child health, immunization, community health workers, digital health, last-mile delivery

JEL code(s)

Secondary IDs

Prior work

This trial does not extend or rely on any prior RCTs.

Abstract

This study evaluates the impact of Dimagi's Connect Child Health Campaign (CHC), a community-based outreach model delivered by locally led organizations in northern Nigeria, on household-level reach and coverage of child-health services. Frontline workers conduct door-to-door outreach with households containing young children to increase awareness, demand, and uptake of selected preventive and basic curative child-health interventions. The evaluation uses a cluster randomized controlled trial (cRCT) with randomization at the ward level, stratified by baseline service coverage and selected contextual characteristics. The study covers 80 wards across four states in northern Nigeria (Kaduna, Kano, Jigawa, and Gombe): 40 wards will be randomly assigned to receive the CHC model and 40 to continue receiving existing government and community health services. Within each ward, the study team will randomly select three enumeration areas, conduct a full household listing, and randomly sample 10 eligible households per enumeration area, for a total planned sample of approximately 2,400 households. Households are eligible if they contain at least one child expected to remain under age 5 at endline. Primary outcomes include household exposure to frontline workers, deworming coverage, household availability of oral rehydration solution (ORS), and selected immunization indicators, including diphtheria-pertussis-tetanus (DPT)-containing vaccine coverage and zero-dose prevalence; Vitamin A supplementation may also be assessed where coordinated with state programs. Secondary outcomes include caregiver knowledge of ORS, recent child illness and care-seeking behavior, and measures of communication quality, trust, and referral experience during frontline worker interactions.

External Link(s)

Registration Citation

Citation

Parkerson, Doug. 2026. "Scalable Accountability for Last-Mile Child Health Service Delivery: A Cluster-Randomized Trial of Dimagi's Connect Child Health Campaign in Nigeria." AEA RCT Registry. September 28. https://doi.org/10.1257/rct.19508-1.0

Sponsors & Partners

Partner

Name

Dimagi, Inc

Type

private_company

URL

https://dimagi.com

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Experimental Details

Interventions

Intervention(s)

The Connect Child Health Campaign (CHC) is a community-based outreach model developed by Dimagi and implemented through locally led organizations in four states in northern Nigeria. Frontline workers conduct door-to-door engagement with households containing young children, with the goal of increasing awareness, demand, and uptake of selected preventive and basic curative child-health interventions, including deworming, oral rehydration solution (ORS), and immunization services. The model combines four features: digitally managed implementation through standardized mobile workflows; remote verification of outreach activity through geo-, time-, and photo-based systems; performance-linked implementation management; and delivery through multiple locally led organizations rather than a single vertically integrated delivery structure.

Intervention Start Date

2026-08-24

Intervention End Date

2026-10-31

Primary Outcomes

Primary Outcomes (end points)

Household exposure to frontline workers; deworming coverage; household availability of oral rehydration solution (ORS); diphtheria-pertussis-tetanus (DPT)-containing vaccine coverage; zero-dose prevalence.

Primary Outcomes (explanation)

Outcomes are measured through household surveys conducted at baseline and endline. Where available, enumerators verify reported services and immunization status against child health cards and vaccination records; other outcomes rely on caregiver report.

Secondary Outcomes

Secondary Outcomes (end points)

Caregiver knowledge of ORS; recent caregiver-reported child illness (diarrhea, fever, cough, or difficulty breathing); care-seeking behavior for recent child illness; ORS and zinc treatment for diarrhea; communication quality and trust during frontline worker interactions; referral and follow-up experiences.

Secondary Outcomes (explanation)

Measured through the same household surveys at baseline and endline, based primarily on caregiver report.

Experimental Design

Two-arm cluster randomized controlled trial (cRCT) with randomization at the ward level. Eighty wards across four states in northern Nigeria (Kaduna, Kano, Jigawa, Gombe) are randomized to treatment (40 wards, receiving the CHC model) or control (40 wards, continuing existing government and community-based health services) following baseline data collection. Within each ward, three enumeration areas are randomly selected, a full household listing is conducted, and 10 eligible households are randomly sampled per enumeration area (approximately 30 households per ward; approximately 2,400 households total). Eligible households contain at least one child expected to remain under age 5 at endline. A baseline survey of frontline workers affiliated with implementing organizations is also conducted.

Experimental Design Details

Not available

Randomization Method

The research team generated a large number of candidate allocations (on the order of 100,000), each constructed to split treatment and control exactly evenly by state and as evenly as possible within each LGA (never off by more than one ward). Candidate allocations were dropped if they showed poor baseline balance between treatment and control on a ward-level service coverage index (combining deworming coverage, ORS use, frontline-worker home-visit coverage, and zero-dose prevalence), a poverty measure (average Poverty Probability Index likelihood), a facility-access measure (share of households more than an hour from the nearest health facility), or the share of households reporting farming as their main livelihood. Among the remaining candidates, the best 10 percent by overall balance were retained, and the final allocation was drawn at random from that well-balanced set.

Randomization Unit

Ward

Was the treatment clustered?

Yes

Experiment Characteristics

Sample size: planned number of clusters

80 wards

Sample size: planned number of observations

Approximately 2,400 households

Sample size (or number of clusters) by treatment arms

Treatment: 40 wards, approximately 1,200 households. Control: 40 wards, approximately 1,200 households.

Minimum detectable effect size for main outcomes (accounting for sample design and clustering)

Power calculations assume a two-arm cluster randomized trial with 40 treatment wards and 40 control wards, with 30 households sampled per ward, for a total sample of 2,400 households, and conservatively assume 30 age-eligible children per ward for child-level outcomes. Statistical power is set at 80 percent with a two-sided significance level of 0.05. Intra-cluster correlation is assumed to range from 0.01 to 0.05, with 0.02 as the central planning assumption. Under these assumptions, the design can detect differences of approximately 6 to 8 percentage points for many binary coverage outcomes in the pooled sample; for zero-dose prevalence, assumed at 20 to 25 percent in the control group, the design can detect reductions of roughly 5 to 7 percentage points. The study is not powered for precise state-specific estimates, and subgroup and heterogeneity analyses should be treated as exploratory. All primary analyses will control for baseline values of outcomes where available, which is expected to improve precision relative to endline-only comparisons; this gain is not incorporated into the calculations above, which should be viewed as conservative.

Supporting Documents and Materials

IRB

Institutional Review Boards (IRBs)

IRB Name

Innovations for Poverty Action IRB – USA

IRB Approval Date

2026-06-25

IRB Approval Number

IPA Project ID 17746

IRB Name

Gombe State Ministry of Health Research Ethics Committee (GHREC)

IRB Approval Date

2026-05-07

IRB Approval Number

GMHREC 2026/019

IRB Name

Kaduna State Ministry of Health Research Ethics Committee (KADSMHREC)

IRB Approval Date

2026-05-12

IRB Approval Number

MOH/ADM/744/VOL.1/1110096

IRB Name

Kano State Ministry of Health Health Research Ethics Committee (SHREC)

IRB Approval Date

2026-05-13

IRB Approval Number

SHREC/2026/7708

IRB Name

Jigawa State Ministry of Health Research Ethics Committee (JGHREC)

IRB Approval Date

2026-06-18

IRB Approval Number

JGHREC/2026/2710

Analysis Plan