Article Text

Using discrete choice experiments to design interventions for heterogeneous preferences: protocol for a pragmatic randomised controlled trial of a preference-informed, heterogeneity-focused, HIV testing offer for high-risk populations
  1. Jan Ostermann1,2,3,4,
  2. Bernard Njau5,
  3. Amy Hobbie3,4,
  4. Tara Mtuy5,6,
  5. Martha L Masaki5,
  6. Aisa Shayo5,
  7. Marco van Zwetselaar5,
  8. Max Masnick7,
  9. Brian Flaherty8,
  10. Derek S Brown9,
  11. Axel C Mühlbacher4,10,11,
  12. Nathan M Thielman3,4
  1. 1Department of Health Services Policy & Management, University of South Carolina, Columbia, South Carolina, USA
  2. 2South Carolina Smart State Center for Healthcare Quality, University of South Carolina, Carolina, South Carolina, USA
  3. 3Duke Global Health Institute, Duke University, Durham, North Carolina, USA
  4. 4Center for Health Policy & Inequalities Research, Duke University, Durham, North Carolina, USA
  5. 5Kilimanjaro Christian Medical Centre, Moshi, Tanzania
  6. 6Department of Global Health and Development, London School of Hygiene and Tropical Medicine, London, UK
  7. 7Selway Labs, LLC, Barrington, Rhode Island, USA
  8. 8Department of Psychology, University of Washington, Seattle, Washington, USA
  9. 9Brown School, Washington University in St. Louis, St. Louis, Missouri, USA
  10. 10Institut Gesundheitsökonomie und Medizinmanagement, Hochschule Neubrandenburg, Neubrandenburg, Germany
  11. 11Department of Population Health Sciences, Duke University, Durham, North Carolina, USA
  1. Correspondence to Dr Jan Ostermann; jano{at}


Introduction Approximately one million undiagnosed persons living with HIV in Southern and Eastern Africa need to test for HIV. Novel approaches are necessary to identify HIV testing options that match the heterogeneous testing preferences of high-risk populations. This pragmatic randomised controlled trial (PRCT) will evaluate the efficacy of a preference-informed, heterogeneity-focused HIV counselling and testing (HCT) offer, for improving rates of HIV testing in two high-risk populations.

Methods and analysis The study will be conducted in Moshi, Tanzania. The PRCT will randomise 600 female barworkers and 600 male Kilimanjaro mountain porters across three study arms. All participants will receive an HIV testing offer comprised of four preference-informed testing options, including one ‘common’ option—comprising features that are commonly available in the area and, on average, most preferred among study participants—and three options that are specific to the study arm. Options will be identified using mixed logit and latent class analyses of data from a discrete choice experiment (DCE). Participants in Arm 1 will be offered the common option and three ‘targeted’ options that are predicted to be more preferred than the common option and combine features widely available in the study area. Participants in Arm 2 will be offered the common option and three ‘enhanced’ options, which also include HCT features that are not yet widely available in the study area. Participants in Arm 3, an active control arm, will be offered the common option and three predicted ‘less preferred’ options. The primary outcome will be uptake of HIV testing.

Ethics and dissemination Ethical approval was obtained from the Duke University Health System IRB, the University of South Carolina IRB, the Ethics Review Committee at Kilimanjaro Christian Medical University College, Tanzania’s National Institute for Medical Research, and the Tanzania Food & Drugs Authority (now Tanzania Medicines & Medical Devices Authority). Findings will be published in peer-reviewed journals. The use of rigorous DCE methods for the preference-based design and tailoring of interventions could lead to novel policy options and implementation science approaches.

Trial registration number NCT02714140.

  • hiv & aids
  • public health
  • public health
  • statistics & research methods
  • health economics

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  • Contributors JO, NT and BN conceptualised the study. AH, ACM, BF, BN, DSB, JO and NT were involved in the development and submission of the funding application. All authors contributed to the development of the study protocol. JO and NT contributed equally to the development of this manuscript, wrote the first draft of the manuscript, and led subsequent revisions. MM developed the comet software for the collection of DCE data on iPads. AH, ACM, AS, BF, BN, DSB, JO, MLM, MM, MvZ, NT and TM read the manuscript and provided critical input. All authors read and approved the final manuscript.

  • Funding This study is supported by a grant from the National Institute of Mental Health (R01MH106388).

  • Disclaimer The funding body has no role in the design of the study, the collection, analysis, and interpretation of data or writing of the manuscript.

  • Competing interests None declared.

  • Consent for publication All authors of the manuscript have read and agreed to its content and are accountable for all aspects of the accuracy and integrity of the manuscript in accordance with ICMJE criteria.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data sharing is not yet applicable as datasets have not yet been generated and/or analysed for this study. Data from the proposed study will be stored in a data repository; data will be deidentified so that they cannot be linked back to individuals. Investigators wishing to use study data to answer new research questions may submit data analysis concept proposals for consideration by the Principal Investigators. The Principal Investigators will review the proposals in the context of relevant Data Transfer Agreements and will provide those submitting permissible, scientifically rigorous, and promising proposals access to the data repository to address their research questions.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.