Nonadherence to treatment protocol in published randomised controlled trials: a review

Table 3 Breakdown of persistence and adherence reporting in 88 trials with longitudinal intervention periods

		Short-term intervention (n = 22)	Long-term intervention (n = 66)	Total
Persistence
Fully reported^a		12	31	43
Partially reported only^b		5	20	25
Partially reported, including reporting the number of participants who:
	Withdrew	1	3	4
	Withdrew consent	1	2	3
	Lost to follow-up (during treatment)	-	3	3
	Lost to follow-up (unclear whether during treatment)	1	1	2
	Discontinued due to certain event(s)^c	-	6	6
	Completed study	3	8	11
	Discontinued study	-	2	2
	Completed different aspects of treatment protocol (reported separately)^d	-	2	2
	Completed treatment in trial overall (not by treatment group)	1	1	2
Not reported		5	15	20
Adherence over implementation period
Fully or partially reported, including reporting^b		5	22 (6)	27 (6)
	Average measure of participant adherence^e	2	20 (6)	22 (6)
	Average measure of adherence on part of treatment provider	3	1	4
	Treatment interruptions	-	2	2
Not reported		17	38	55
Overall reporting
Some reporting		19	62	81
	Persistence reported only (fully or partially)	14	34	48
	Adherence reported only (fully or partially)	2	11	13
	Both persistence and adherence reported (fully or partially)	3	17	20
Not reported		3	4	7

^aReported the number of participants still taking treatment at end of treatment period, or the number who completed treatment, or who discontinued or withdrew from randomised intervention prematurely. ^bTrial publications may have reported on one more than one of the categories listed. ^cReported numbers discontinuing only for one reason (for example, adverse events). ^dUnable to discern how many participants received entire intervention. ^eFigure in brackets indicates number of publications reporting adherence measure for overall trial or combinations of intervention groups, not by individual intervention group.

ISSN: 1745-6215