We purposefully considered the number of HCs in a district for our sampling because this may influence the number of external supervisors in a team and how much time the supervision team spends on field visits to HCs, which we assumed could impact the supervision experience among supervisors and providers. We therefore included a supervision team from a district with a high number of HCs, a team with few HCs and a team from a district with an average number of HCs. To optimise the chance of retrieving precise recollections, we asked providers from the HC most recently supervised in each of these three districts to participate in a provider discussion. For the same reason, we excluded providers who had not experienced supervision in the past 6 months. HC managers were excluded from the provider FGDs with the intention to set a discussion among peers and reduce social desirability bias. FGDs took place in undisturbed rooms at participants’ main work facility, and participants were offered a drink.