Looking inside the black box: results of a theory-based process evaluation exploring the results of a randomized controlled trial of printed educational messages to increase primary care physicians’ diabetic retinopathy referrals [Trial registration number ISRCTN72772651]

Table 1 Participant flow by group

*Retinopathy screening (N=437)*
		Insert	No insert
Outsert	Patient Reminder Note	n=252 Baseline questionnaires sent n=144 Baseline non-response	n=252 Baseline questionnaires sent n=136 Baseline non-response
		n=36 Follow-up attrition	n=34 Follow-up attrition
		n=5 Excluded	n=6 Excluded
		n=67 Analysed	n=76 Analysed
	No Patient Reminder Note	n=252 Baseline questionnaires sent n=150 Baseline non-response	n=252 Baseline questionnaires sent n=146 Baseline non-response
		n=20 Follow-up attrition	n=29 Follow-up attrition
		n=6 Excluded	n=4 Excluded
		n=76 Analysed	n=73 Analysed
No Outsert	No Patient Reminder Note	n=252 Baseline questionnaires sent n=141 Baseline non-response	n=252 Baseline questionnaires sent n=146 Baseline non-response
		n=33 Follow-up attrition	n=24 Follow-up attrition
		n=5 Excluded	n=10 Excluded
		n=73 Analysed	n=72 Analysed

ISSN: 1748-5908