Evidence map›Paper›PMID 40063069›Full record

Trial reportJournal of medical Internet research2025

Optimizing Engagement With a Smartphone App to Prevent Violence Against Adolescents: Results From a Cluster Randomized Factorial Trial in Tanzania.

Roselinde Janowski, Lucie D Cluver, Yulia Shenderovich, Joyce Wamoyi, Mwita Wambura, David Stern, Lily Clements, G J Melendez-Torres, Lauren Baerecke, Abigail Ornellas and 8 more

Abstract readRandomized Controlled Trial
In one paragraph

Trial report in Journal of medical Internet research, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.

0numbers the graph read from it
0cells of the map it votes in
3citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

3 citing papers in PubMed.

  1. Article
  2. Article
  3. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

18 authors.

Roselinde JanowskiDepartment of Social Policy and Intervention, University of Oxford, Oxford, United Kingdom.ORCID 0000-0003-2082-9281
Lucie D CluverDepartment of Social Policy and Intervention, University of Oxford, Oxford, United Kingdom.ORCID 0000-0002-0418-835X
Yulia ShenderovichCentre for Development, Evaluation, Complexity, and Implementation in Public Health Improvement (DECIPHer), School of Social Sciences, Cardiff University, Cardiff, United Kingdom.ORCID 0000-0002-0254-3397
Joyce WamoyiMwanza Research Centre, National Institute for Medical Research, Mwanza, United Republic of Tanzania.ORCID 0000-0002-2956-8666
Mwita WamburaMwanza Research Centre, National Institute for Medical Research, Mwanza, United Republic of Tanzania.ORCID 0000-0002-9384-6712
David SternInnovations in Development, Education and the Mathematical Sciences (IDEMS) International, Reading, United Kingdom.ORCID 0000-0003-3806-9313
Lily ClementsInnovations in Development, Education and the Mathematical Sciences (IDEMS) International, Reading, United Kingdom.ORCID 0000-0001-8864-0552
G J Melendez-TorresFaculty of Health and Life Sciences, University of Exeter, Exeter, United Kingdom.ORCID 0000-0002-9823-4790
Lauren BaereckeCentre for Social Science Research, University of Cape Town, Cape Town, South Africa.ORCID 0000-0002-9999-509X
Abigail OrnellasCentre for Social Science Research, University of Cape Town, Cape Town, South Africa.ORCID 0000-0003-0751-4752
Angelique Nicole ChettyCentre for Social Science Research, University of Cape Town, Cape Town, South Africa.ORCID 0000-0002-2040-1915
Jonathan KlapwijkDepartment of Social Policy and Intervention, University of Oxford, Oxford, United Kingdom.ORCID 0000-0002-0078-1826
Laetitia ChristineInnovations in Development, Education and the Mathematical Sciences (INNODEMS), Kakamega, Kenya.ORCID 0009-0006-3087-5109
Ateamate MukabanaInnovations in Development, Education and the Mathematical Sciences (INNODEMS), Kakamega, Kenya.ORCID 0009-0008-3077-0598
Esmee Te WinkelInnovations in Development, Education and the Mathematical Sciences (IDEMS) International, Reading, United Kingdom.ORCID 0009-0009-9970-596X
Anna BooijClowns Without Borders South Africa, Cape Town, South Africa.ORCID 0009-0000-4077-3989
Gervas MbosoliMwanza Research Centre, National Institute for Medical Research, Mwanza, United Republic of Tanzania.ORCID 0009-0002-9817-4027
Jamie M LachmanDepartment of Social Policy and Intervention, University of Oxford, Oxford, United Kingdom.ORCID 0000-0001-9475-9218

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundViolence and abuse exert extensive health, social, and economic burdens on adolescents in low- and middle-income countries. Digital parenting interventions are promising for mitigating risks at scale. However, their potential for public health impact hinges on meaningful engagement with the digital platform.

objectiveThe objective of this study was to evaluate the impact of 3 intervention design and implementation factors aimed at increasing engagement with a noncommercialized, offline-first smartphone app for caregivers of adolescents in Tanzania, in partnership with the United Nations Children's Fund, the World Health Organization, and the Tanzanian national government.

methodsFollowing Multiphase Optimization Strategy (MOST) principles, we conducted a 2×2×2 cluster randomized factorial trial involving caregivers of adolescents aged 10 to 17 years. Caregivers were recruited by community representatives from 16 urban and periurban communities (ie, clusters) in the Mwanza region of Tanzania. Each cluster was randomized to 1 of 2 levels of each factor: guidance (self-guided or guided via facilitator-moderated WhatsApp groups), app design (structured or unstructured), and preprogram digital support (basic or enhanced). Primary outcomes were automatically tracked measures of engagement (app launches, modules completed, and home practice activities reviewed), with secondary outcomes including modules started, time spent in the app, and positive behaviors logged. Generalized linear mixed-effects models assessed the impact of experimental factors on engagement.

resultsAutomatically tracked engagement data from 614 caregivers were analyzed, of which 205 (33.4%) were men. Compared to self-guided participants, receiving guidance alongside the app led to significantly more app launches (mean ratio [MR] 2.93, 95% CI 1.84-4.68; P<.001), modules completed (MR 1.29, 95% CI 1.05-1.58; P=.02), modules started (MR 1.20, 95% CI 1.02-1.42; P=.03), time spent in the app (MR 1.45, 95% CI 1.39-1.51; P<.001), and positive behavior logs (MR 2.73, 95% CI 2.07-3.60; P<.001). Compared to the structured design, unstructured design use resulted in significantly more modules completed (MR 1.49, 95% CI 1.26-1.76; P<.001), home practice activity reviews (MR 7.49, 95% CI 5.19-10.82; P<.001), modules started (MR 1.27, 95% CI 1.06-1.52; P=.01), time spent in the app (MR 1.84, 95% CI 1.70-1.99; P<.001), and positive behavior logs (MR 55.68, 95% CI 16.48-188.14; P<.001). While analyses did not detect an effect of enhanced digital support on directly observed engagement, the combination of enhanced digital support and guidance positively influenced engagement across a range of outcomes.

conclusionsThis study is the first to systematically optimize engagement with a digital parenting intervention in a low- and middle-income country. Our findings offer important learnings for developing evidence-based, scalable digital interventions in resource-constrained settings.

trial registrationPan-African Clinical Trial Registry PACTR202210657553944; https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=24051. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s12889-023-15989-x.

Indexed as

Mobile ApplicationsSmartphoneViolenceAdolescentCaregiversChildFemaleHumansMaleTanzaniaadolescentsdigital healthengagementlow- and middle-income countrymobile phoneMultiphase Optimization Strategyparentingrandomized factorial experimentviolence against children

Identifiers

PMID40063069
PMCPMC11933756

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LicenceCC BY
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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.