Chanjo Kwa Wakati - Improving Vaccination Coverage and Timeliness in Rural Settings

Study Overview
=================
Brief Summary
-----------------
Background and Objective: Tanzania is one of 20 countries where the majority of un- and under-vaccinated children reside. Prior research identified substantial rural-urban disparities in rates and timeliness of childhood vaccination in Tanzania, with children in rural settings being more like to receive delayed or no vaccinations. This type 1 effectiveness implementation hybrid study will evaluate the effect of Chanjo Kwa Wakati (Timely Vaccination in Kiswahili), a community-based, integrated digital health intervention, on vaccination timeliness. The intervention combines a vaccination knowledge intervention, mobile phone-based reminders, and incentives with the goal to promote timely childhood vaccinations. Methods: The study will be conducted in two predominantly rural regions in Tanzania with high numbers of un- or under-vaccinated children. Forty rural health facilities and their catchment areas (clusters) will be randomized to an early or delayed onset study arm. From each cluster, three cohorts of mother-child dyads, one retrospective cohort and two prospective cohorts, will be enrolled into the study. For all vaccines due during the first year of life, timeliness (primary outcome) and coverage (secondary outcome) will be observed for 1200 children (600 intervention children and 600 non-intervention children). Study logs, fidelity checklists, quantitative surveys, vaccination records, and qualitative interviews with mothers and key informants will be used to inform the five constructs of the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework. Results will be used to develop an implementation blueprint that can guide future adaptations, sustainability, and scale-up of Chanjo Kwa Wakati. Hypothesis: The hypothesis is that Chanjo Kwa Wakati is effective for increasing the timeliness of childhood vaccinations due by age 1 year compared to the standard of care. Expected impact: This study will address the lack of rigorous evidence on the effectiveness of an community-based digital health intervention for promoting vaccination coverage and timeliness among children from sub-Saharan Africa, and identify implementation strategies to facilitate the deployment of integrated vaccination interventions in low- and middle-income country settings.

Official Title
-----------------
Chanjo Kwa Wakati - Leveraging Community Health Workers and a Responsive Digital Health System to Improve Vaccination Coverage and Timeliness in Rural Settings

Conditions
-----------------
Vaccination, Short Message Service (SMS), Incentives, Knowledge, Attitudes, Practice

Intervention / Treatment
-----------------
* Behavioral: Chanjo Kwa Wakati - Knowledge Intervention
* Behavioral: Chanjo Kwa Wakati - Reminders
* Behavioral: Chanjo Kwa Wakati - Incentives
* Behavioral: Chanjo Kwa Wakati - Service notifications


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria for the Cross-sectional sample: mothers of children ages 12-23 months residing in the sampling area Inclusion Criteria for the Longitudinal sample: pregnant women in their last trimester of pregnancy residing in the sampling area expected to reside in the sampling area until the child reaches age 1 year Exclusion Criteria: Women who are not living in catchment areas of participating health facilities (which routinely provide maternal and child health services, including antenatal care and at least weekly routine childhood immunization. Facilities must be operational, must have at least 2 community health workers, and must have reported at least 100 pregnancies or births in the year prior to study implementation.)

Ages Eligible for Study
-----------------
Minimum Age: 15 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This type 1 effectiveness-implementation hybrid study uses a cluster-randomized trial design to evaluate intervention effectiveness.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Early onset<br>20 clusters will be assigned to the early onset arm. A cross-sectional cohort and two longitudinal cohorts will be enrolled from each cluster. Both longitudinal cohorts will receive all components of the Chanjo Kwa Wakati intervention. | Behavioral: Chanjo Kwa Wakati - Knowledge Intervention<br>* Counseling scripts assessing and addressing vaccination-related knowledge gaps<br>Behavioral: Chanjo Kwa Wakati - Reminders<br>* Reminders of upcoming vaccination due dates, sent to the mother's mobile phone<br>Behavioral: Chanjo Kwa Wakati - Incentives<br>* Conditional incentives for timely vaccination, tailored to each child's vaccination schedule<br>Behavioral: Chanjo Kwa Wakati - Service notifications<br>* Service notifications (e.g., related to stockouts or service non-availability), sent to the mother's mobile phone<br>|
| Experimental: Delayed onset<br>20 clusters will be assigned to the delayed onset arm. A cross-sectional cohort and two longitudinal cohorts will be enrolled from each cluster. The second longitudinal cohort will receive all components of the Chanjo Kwa Wakati intervention. | Behavioral: Chanjo Kwa Wakati - Knowledge Intervention<br>* Counseling scripts assessing and addressing vaccination-related knowledge gaps<br>Behavioral: Chanjo Kwa Wakati - Reminders<br>* Reminders of upcoming vaccination due dates, sent to the mother's mobile phone<br>Behavioral: Chanjo Kwa Wakati - Incentives<br>* Conditional incentives for timely vaccination, tailored to each child's vaccination schedule<br>Behavioral: Chanjo Kwa Wakati - Service notifications<br>* Service notifications (e.g., related to stockouts or service non-availability), sent to the mother's mobile phone<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Penta 3 delay in days (continuous) | The average number of days between the Penta3 vaccination due date (at age 14 weeks) and the date on which the child received the vaccination. Dates abstracted from the child's immunization card. | Assessed during the endline survey, an average follow-up period of 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Penta 3 delay > 28 days (binary) | The percentage of participants with a delay >28 days between the Penta 3 vaccination due date (at age 14 weeks) and the date on which the vaccination was received. Dates abstracted from the child's immunization card. | Assessed during the endline survey, an average follow-up period of 1 year | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Childhood vaccinations, Timeliness, Vaccine hesitancy, Digital Health, Community Health Workers, Tanzania, Low and middle-income country, SMS reminder, Conditional incentive