Table 1

Summary of methodological quality assessments

McHarm* criteria	Rating	No of studies (%†)
(1) Were the harms PRE-DEFINED using standardised or precise definitions?	Yes	6 (7)
	No	79 (93)
	Unsure	0
(2) Were SERIOUS events precisely defined?	Yes	2 (2)
	No	83 (98)
	Unsure	0
(3) Were SEVERE events precisely defined?	Yes	0
	No	85 (100)
	Unsure	0
(4) Were the number of DEATHS in each study group specified OR were the reason(s) for not specifying them given?	Yes	10 (12)
	No	75 (88)
	Unsure	0
(5) Was the mode of harms collection specified as ACTIVE?	Yes	46 (54)
	No	37 (44)
	Unsure	2 (2)
(6) Was the mode of harms collection specified as PASSIVE?	Yes	11 (13)
	No	73 (86)
	Unsure	1 (1)
(7) Did the study specify WHO collected the harms?	Yes	22 (26)
	No	63 (74)
	Unsure	0
(8) Did the study specify the TRAINING or BACKGROUND of who ascertained the harms?	Yes	20 (24)
	No	65 (76)
	Unsure	0
(9) Did the study specify the TIMING and FREQUENCY of collection of the harms?	Yes	39 (46)
	No	45 (53)
	Unsure	1 (1)
(10) Did the author(s) use STANDARD scale(s) or checklist(s) for harms collection?	Yes	6 (7)
	No	76 (89)
	Unsure	3 (4)
(11) Did the authors specify if the harms reported encompass ALL the events collected or a selected SAMPLE?	Yes	80 (94)
	No	2 (2)
	Unsure	3 (4)
(12) Was the NUMBER of participants that withdrew or were lost to follow-up specified for each study group?	Yes	24 (28)
	No	61 (72)
	Unsure	0
(13) Was the TOTAL NUMBER of participants affected by harms specified for each study arm?	Yes	16 (19)
	No	69 (81)
	Unsure	0
(14) Did the author(s) specify the NUMBER for each TYPE of harmful event for each study group?	Yes	43 (51)
	No	39 (46)
	Unsure	3 (4)
(15) Did the author(s) specify the type of analyses undertaken for harms data?	Yes	10 (12)
	No	75 (88)
	Unsure	0

↵*Methodological quality of publications/studies as assessed by the McHarm scale.17
↵†Sum of percentages may not total 100 due to rounding.