## 2 Methods
### Data Collection  
Data were collected pre- and post-use of the OHL Self-AsseT. Overall, 19 professionals participated, of whom five participated in both pre- and post-intervention interviews. Six individual interviews were conducted in the pre-intervention phase between March and June 2020; the post-intervention phase included three focus group interviews with, respectively two, three and five participants each (n = 10 participants). Ten further individual interviews were conducted between October 2020 and April 2021 (see Table 1). All participants received written study information beforehand and gave informed consent.  
Interview guides with open-ended questions were developed and used in all interviews. For the pre-intervention data collection, this included questions on participants' perceptions of OHL, the project itself and their motivation for participating, as well as their expectations regarding the tool. For post-intervention interviews, the guide included questions on the use of the OHL Self-AsseT, the interactions and leadership during the process, and changes experienced due to the intervention. Two focus group moderators stimulated discussion on how the changes the intervention had sparked were reflected in daily practice, while ensuring that all participants were able to contribute their perceptions and experiences. Due to the COVID-19 pandemic, all interviews were conducted over a video conferencing system. All were conducted in German or Swiss-German. Focus group discussions lasted 50-80 min, individual interviews 15-60 min (mean: 30 min). Data were video/audio recorded and transcribed verbatim.  
To understand the performance and actions of the self-assessment teams implementing the OHL Self AsseT, we needed minimal quantitative data. We used the ratings per dimension from the checklist (module 2), the full checklist is published by [PERSON] et al. (2019). The collected data from the intervention documentation (i.e., needs for action and planned improvement measures) is exemplary. The full quantitative results are presented elsewhere (17). Our goal was to describe the participating team's performance in relation to emerging qualitative themes in ways that would improve our understanding of the implementation process.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Time** & **Sample** & \
\begin{tabular}{c} **Function within the** \\ **Project** \\ \end{tabular} & **Data Collection** \\ \hline Pre-intervention & 4 medical doctors, 2 HCSO managers & manager supporting the & 6 individual interviews \\ \hline Post-intervention & 4 medical doctors 2 HCSO managers 3 managerial persons &
\begin{tabular}{c} manager supporting the \\ project and/or member of the \\ self-assessment team \\ \end{tabular} & 9 individual interviews \\ \hline Post-intervention & 4 MPAs 3 registered nurses 3 nursing assistants 1 APN & coordinating persons * & 3 focus group interviews, 1 individual interview \\ \hline \hline \end{tabular}  
* Coordinating persons for the OHL Self-AsseT intervention were defined as members of the self-assessment team who took over the coordination of meetings and tasks, including communication with the research team and their managers. Legend: HCSO: home care service organization; MPA: medical practice administrator; APN: advanced practice nurse.  
\end{table}
Table 1: Description of sample and data collection.