Background: Our research team is conducting phenomenological interviews in Kenya with people who have not been able to access community eye health services, aiming to explore the barriers and ideas for potential service modifications. We conducted an embedded study that compared in-person and telephone interview modalities in terms of time requirements, costs, and data richness. Methods: A team of six interviewers conducted 31 in-person interviews and 31 telephone interviews using the same recruitment strategy, topic guide, and analytic matrix for each interview. We compared the mean duration; mean number of themes reported by each participant; total number of themes reported; interviewer rating of perceived richness; interviewer rating of perceived ease of building rapport; number of days taken by the team to complete all interviews; and all costs associated with conducting the interviews in each modality. Findings: In-person interviews were 44% more expensive and took 60% longer to complete than our telephone interviews (requiring 5 days and 3 days respectively). The average in-person interview lasted 110 seconds longer than the average telephone interview (p=0.05) and generated more words and themes. However, the full set of interviews from both approaches identified similar numbers of barriers (p=0.14) and the same number of solutions (p=0.03). Interviewers universally felt that the in-person approach was associated with better rapport and higher quality data (p=0.01). Triangulation of themes revealed good agreement, with 88% of all solutions occurring in both sets, and no areas of thematic dissonance. Discussion: The in-person approach required more time and financial resources, but generated more words and themes per person, and was perceived to afford richer data by interviewers. However, this additional richness did not translate into a greater number of themes that our team can act upon to improve services.

The authors have declared no competing interest.

This study is supported by the National Institute for Health Research (NIHR) (using the UKs Official Development Assistance (ODA) Funding) and Wellcome [215633/Z/19/Z] under the NIHR-Wellcome Partnership for Global Health Research. The views expressed are those of the authors and not necessarily those of Wellcome, the NIHR or the Department of Health and Social Care.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study was granted ethical approval by the Kenya Medical research Institute (KEMRI) scientific and ethics review unit on November 30th 2022, Kenya National Commission For Science, Technology & Innovation (NACOSTI) on 12th January 2023, and the London School of Hygiene and Tropical Medicine (LSHTM) ethics committee on 5th May 2023.

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Data produced in the present study are available upon reasonable request to the authors