2.4.1. Conventional Face-to-Face Training (F2F)

The conventional F2F training consists of a six-day classroom training facilitated by two experienced counselors with certification as Master Trainers, meaning that they have significant experience delivering the HAP to patients with depression in clinical settings, have completed instruction in being an effective trainer, and have provided training to other health workers in the delivery of the HAP. This conventional in-person training is considered the 'gold-standard' in training non-specialist health workers based on the prior methods employed in the evaluation and delivery of the HAP treatment [35]. The six-day training is hosted in a community setting and follows the content in the HAP manuals. This form of in-person training is consistent with the type of training currently available to non-specialist health workers in the district.

#### 2.4.2. Digital Training (DGT)

DGT consists of a digitized version of the HAP manuals hosted on the Moodle Learning Management System and accessible through a smartphone app [54]. The training program content was divided across 16 modules following the same structure as the F2F instruction. The modules consisted of expert lecture videos, role-play videos showing clinical scenarios, PowerPoint presentations, reading materials, interactive quizzes embedded within the modules, and assessment questions at the end of each module. Duration of digital training content was matched to the duration of the F2F training, and consisted of approximately 48 h, covering the time required to view the content, read the accompanying materials, and complete the interactive quizzes and assessment questions. Participants were provided with a smartphone to access the training program and were invited to attend a short orientation session to learn how to use the phone, access the instructional content through the smartphone app, and navigate the Learning Management System interface. Participants were provided with a 30-day window to complete the digital training. Throughout the training, participants could contact our research team for technical assistance regarding any concerns or challenges with using the smartphone or accessing the training program content.

### 2.4.3. Digital Training with Remote Support (DGT+)

The DGT+ training program includes access to the same smartphone app, digital training content, and technical support described above for the DGT program. DGT+ included the addition of remote support from the research team. This involved weekly phone calls from a research assistant to participants. The purpose of the support phone calls was to check in with participants about their progress with the training, and whether they had experienced any challenges or had questions about the digital platform or program content. The research assistant also provided participants with encouragement and praise during the calls as a way to motivate participants and support engagement in the training.
