Delivery Contexts

PROGROUP could tolerate variation in provider, location, and referral organisation if group identity formation and participation were protected. Facilitators needed skill in managing group processes more often than additional diet or weight-management knowledge. Not all influential contexts were under PROGROUP's control, including family support, social support, service capacity, and system overload. Venue, accessibility, travel burden, and transport support affected attendance and retention. Transport problems worsened attrition, while reimbursing travel costs helped retention and punctuality.