Understanding the barriers and facilitators to using self-sampling packs for sexually transmitted infections and blood borne viruses: thematic analyses supporting intervention optimisation

Purpose This paper illustrates initial steps of an intervention optimisation process. Self-sampling packs for sexually transmitted infections (STIs) and blood borne viruses (BBVs) are widely offered within the UK, yet have problems with reach and sample return rates. They have arisen without any formal intervention development. Methods Eleven focus groups and seven interviews were conducted with convenience samples of patients recruited from sexual health clinics and members of the public in late 2017 (n=57). To enable intervention optimisation firstly we formulated initial programme theory situating the intervention. Secondly, we conducted an inductive appraisal of the behavioural system of using the pack to understand meaningful constituent behavioural domains. Subsequently we conducted a thematic analysis of barriers and facilitators to enacting each sequential behavioural domain in preparation for future behaviour change wheel analysis. Results Overall, we found that self-sampling packs were acceptable. Our participants understood their overall logic and value as a pragmatic intervention that simultaneously reduced barriers to, and facilitated, individuals being tested for STIs. However, at the level of each behavioural domain (e.g., reading leaflets, returning samples), problems with the pack were identified as well as a series of potential optimisations which might widen the reach of self-sampling and increase the return of viable samples. Conclusions This paper provides an example of a pragmatic approach to optimising an intervention already widely offered across the UK. The paper demonstrates the added value health psychological approaches make; systematically considering the context of the intervention, in addition to illuminating granular areas for improvement. What is already known on this subject? The use of self-sampling packs for sexually transmitted infections (STIs) and blood borne viruses (BBVs) has been widely implemented without in-depth assessment of user engagement or theorisation Some evidence suggests that the uptake of self-sampling packs, and the concomitant return of samples to enable diagnosis, are socially patterned Despite increasing and widespread use of self-sampling packs across the UK, relatively little is currently known about their acceptability, or how they could be improved What does this study add? This study provides an illustrative example of using a preliminary programme theory to situate the problem to be addressed by intervention optimisation The thematic analyses show that self-sampling packs offer a largely acceptable means to enabling STI and BBV testing and diagnosis; they remove many barriers to testing. However, several modifiable barriers to use endure, potentially reducing sample return and amplifying health inequalities This study presents a range of barriers and facilitators to the various behavioural domains included within the use of self-sampling packs. It summarises the findings ready for subsequent behaviour change wheel analyses