Qualitative research and implementation science: Informing the acceptability and implementation of a trial of a conditional cash transfer intervention designed to reduce drug use and HIV risk.

HIV risk remains high among Cambodian female entertainment and sex workers, driven by amphetamine-type substance use and sexual risk. Conditional cash transfer is an evidence-based approach to reduce stimulant use and optimize HIV/AIDS prevention, but questions remain regarding implementation in resource-limited settings. We conducted formative qualitative research to enhance acceptability of a conditional cash transfer intervention aimed at reducing amphetamine-type substance use and HIV risk among female entertainment/sex workers and inform implementation as part of a large cluster randomized trial. We conducted in-depth interviews with 30 female entertainment/sex workers. Interviews were digitally recorded and conducted and transcribed in Khmer. English transcripts were read for emerging themes and an initial coding scheme was developed. Data were coded using open and axial coding to clarify and consolidate initial themes. While most participants expressed enthusiasm for the intervention, financial and transportation issues emerged as key barriers to participation. The proposed incentive of USD$1 per screen was regarded as unacceptable and participants identified a need for transportation assistance. Participants also expressed concerns about directly observed urine specimen collection. Finally, while most participants found the 4-week aftercare program acceptable, the need for enjoyable as well as educational content was emphasized. Revisions to the protocol taking these data into account were made to optimize the acceptability of the intervention and the implementation of the trial. Findings identified key concerns and preferences that were taken into account in the final trial protocol. In particular, financial and transportation issues were identified as critical barriers to participation, with the potential to impact both intervention uptake and trial feasibility. Results demonstrate the value of formative qualitative research for clinical trial planning and implementation, particularly in settings where little is known about acceptability of interventions or willingness to participate.