A systematic review with attempted network meta-analysis of asthma therapy recommended for five to eighteen year olds in GINA steps three and four

Table 2 Risk of bias in included trials

Study ID[ref]	1 [19]	2 [20]	3 [21]	4 [22]	5 [23]	6 [24]	7 [25]	8 [26]	9 [7]	10 [9]	11 [27]	12 [28]	13 [29]	14 [30]	15 [31]	16 [8]	17 [32]	18 [33]	19 [6]	20 [34]	21 [10]	22 [35]	23 [36]	Y	N	?
Sequence generation	?	?	?	Y	?	Y	?	?	Y	?	?	?	Y	Y	?	?	Y	?	Y	?	Y	?	Y	9	0	14
Allocation concealment	?	?	Y	Y	?	?	?	?	Y	?	?	?	?	?	?	?	Y	?	?	?	?	?	Y	5	0	18
Appropriate blinding of participants	?	N	Y	N	?	?	?	Y	N	Y	?	?	?	?	?	?	Y	?	Y	?	?	N	Y	6	4	13
Appropriate blinding of outcome assessors	?	Y	Y	N	?	?	?	Y	?	Y	?	?	?	?	?	?	?	?	?	?	?	N	Y	5	2	16
Appropriate blinding of physician	?	?	Y	N	?	?	?	Y	?	Y	?	?	?	?	?	?	?	?	?	?	?	N	Y	4	2	17
Registration of loss to follow-up	Y	Y	?	?	Y	Y	?	?	Y	Y	Y	Y	Y	Y	Y	?	?	Y	?	Y	Y	Y	Y	16	0	7
Way missing values were dealt with	?	?	?	Y	?	?	?	?	Y	?	?	?	?	?	?	?	Y	Y	?	?	?	?	?	4	0	19
Compliance checked	Y	?	?	Y	Y	?	?	?	Y	?	?	Y	Y	Y	?	Y	?	Y	?	?	Y	?	Y	11	0	12
Selective reporting	?	?	?	?	?	N	?	?	?	?	?	?	?	?	?	?	?	?	?	?	?	?	?	0	1	22
Total times “Yes”	2	2	4	4	2	2	0	3	5	4	1	3	3	3	1	1	4	3	2	1	3	1	7
Overall score Y/N/?																								60	9	138

Each trial could score “yes” for a low, “no” for a high and “?” for an uncertain risk of bias, respectively.
The 9 items are based on a combination of the Cochrane approach to assess the risk of bias, combined with the validity checklist of Jadad et al. [17, 18].

ISSN: 1471-2466