Table 1.

The factors affecting the recruitment and randomisation process

Participant recruitment	Contact between participant and facilitator
	Ongoing	One-off contact (at facilitation)
Area/location not restricted	MODEL B Randomise facilitators and participants Intervention facilitators only to be trained	MODEL A Randomise facilitators and participants Intervention facilitators only to be trained
Within a specific geographical (or other prespecified) area	MODEL C Train intervention facilitators only Randomise facilitators only Participants within each area allocated to facilitator (not randomised)	MODEL D Train all facilitators Randomise participants