{
  "abstract": "Objectives Low intervention uptake and contamination can dilute effects of cluster randomised trials (CRTs). We investigated the feasibility of digital fingerprints to assess intervention coverage and contamination in a CRT of community-based sexual and reproductive health services for youth (CHIEDZA).Methods 24 clusters in Zimbabwe were randomly allocated to intervention/control. In intervention clusters, CHIEDZA services were provided in community halls for 30 months. A population-based survey of youth aged 18–24 (700/cluster) was conducted to ascertain impact. Digital fingerprints were collected from service attendees and survey participants, and the datasets were linked to assess intervention coverage at population level in intervention clusters and contamination in control clusters. Multilevel logistic regression estimated the association of hall distance with service uptake.Results Between April 2019 and March 2022, 36 991 clients attended the CHIEDZA service and 99.9% used biometric registration. In the survey 13 675/17 682 (77.3%) participants completed biometric registration: 1182 refused, 1235 bypassed and 1590 could not register.CHIEDZA service coverage in the intervention clusters was 23.1% and contamination was 3.7%. Against biometric registration match, self-reported service attendance had 75.3% sensitivity (95% CI 73.1% to 77.5%) and 92.7% specificity (95% CI 92.0% to 93.4%). Odds of CHIEDZA service use reduced by 52% for every 1km distance (OR: 0.48 95% CI 0.44 to 0.54).Discussion Biometric identification was feasible and acceptable in a community setting without time pressure. In population-based surveys additional technological challenges emerged. Biometrics enabled good estimation of intervention coverage and validated self-reported data. Youth community services must overcome distance barriers.Conclusion Biometric identification is useful for assessment of CRT coverage and contamination.Trial registration number https://clinicaltrials.gov/study/NCT03719521.",
  "authors": [
    {
      "affiliations": [
        "MRC International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK",
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe"
      ],
      "name": "Victoria Simms"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe"
      ],
      "name": "Tsitsi Bandason"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe"
      ],
      "name": "Ethel Dauya"
    },
    {
      "affiliations": [
        "MRC International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK",
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe"
      ],
      "name": "Chido Dziva Chikwari"
    },
    {
      "affiliations": [
        "MRC International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK"
      ],
      "name": "Chris Grundy"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe",
        "Department of Global Health and Development, Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, UK"
      ],
      "name": "Mandikudza Tembo"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe"
      ],
      "name": "Constancia Mavodza"
    },
    {
      "affiliations": [
        "AIDS and TB Unit, Ministry of Health and Child Care, Harare, Zimbabwe"
      ],
      "name": "Owen Mugurungi"
    },
    {
      "affiliations": [
        "AIDS and TB Unit, Ministry of Health and Child Care, Harare, Zimbabwe"
      ],
      "name": "Tsitsi Apollo"
    },
    {
      "affiliations": [
        "Simprints, Cambridge, UK"
      ],
      "name": "Riffat Ashrafee"
    },
    {
      "affiliations": [
        "Simprints, Cambridge, UK"
      ],
      "name": "Demetris Demetriou"
    },
    {
      "affiliations": [
        "Simprints, Cambridge, UK"
      ],
      "name": "Anindya Sharma"
    },
    {
      "affiliations": [
        "MRC International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK"
      ],
      "name": "Richard J Hayes"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe",
        "Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK",
        "Institute of Infectious Diseases and Tropical Medicine, LMU University Hospital, Munich, Germany"
      ],
      "name": "Katharina Kranzer"
    },
    {
      "affiliations": [
        "The Health Research Unit Zimbabwe, Biomedical Research and Training Institute, Harare, Harare Province, Zimbabwe",
        "Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK"
      ],
      "name": "Rashida A Ferrand"
    }
  ],
  "title": "Effectiveness and acceptability of biometrics to evaluate intervention coverage and contamination in a cluster randomised trial of community-based sexual and reproductive health services for youth in Zimbabwe",
  "uid": "5c5cd60d-5395-5fbd-b347-6b78e63cabb7"
}