Table 2.

Criteria of quality of assessment and risk of bias summary.

	Was the spectrum of patients representative of the disease studied?	Were the selection criteria (i.e. in-/exclusion criteria) clearly described?	Was the definition of study group adequate (i.e. exacerbation well-defined)?	Did all patients undergo the same tests?	Were multiple inclusions per patients prohibited?	Were positive and/or negative controls used for PCR?	Was the collection of sample documented in sufficient detail?	Was the use of inhaled corticosteroids described?	Was the selection process of the participants clearly described?	Were samples of more than one season included?	Were the patient's characteristics clearly described?	Was the method of patient recruitment consecutive?	Were withdrawals from the study explained?	Were uninterpretable/intermediate test results reported?	Total score
Ringshausen [29]	1	1	1	1	0	1	0	1	0	1	1	0	1	1	10
McManus [10]	1	1	0	1	0	0	1	1	0	1	1	0	0	0	7
McManus [9]	1	1	1	1	0	0	1	0	0	1	0	0	0	1	7
Zakharkina [26]	1	1	1	1	0	1	1	0	0	0	1	1	0	0	8
Rohde [25]	1	1	1	1	0	1	1	1	1	1	1	1	1	0	12
Aaron [21]	0	1	1	1	1	1	1	1	1	1	1	0	1	0	11
Seemungal [13]	1	1	1	0	0	0	1	1	1	0	1	0	1	0	8
Kherad [23]	1	1	1	0	0	0	0	1	1	1	1	1	1	0	9
Camargo [22]	1	1	0	1	1	0	1	1	1	0	1	0	1	0	9
Hutchinson [14]	1	1	1	1	0	0	0	0	0	1	1	0	1	0	7
Seemungal [24]	1	1	1	1	0	1	1	1	1	1	1	0	1	1	12
Papi [18]	1	1	1	1	0	0	1	1	1	1	1	0	1	0	10
Rohde [19]	1	1	1	1	0	1	1	0	1	1	1	0	0	0	9
Ko [17]	1	1	1	0	0	1	1	1	1	1	1	1	1	0	11
McManus [11]	1	1	1	1	0	1	1	1	0	1	1	0	0	1	10
Dimopoulos [12]	1	1	1	0	0	1	0	1	1	1	1	1	1	1	12
Beckham [15]	1	0	1	1	0	1	1	0	1	1	1	0	0	1	10
Tan [20]	1	0	0	0	0	1	1	1	0	1	1	0	0	1	7
Perotin [27]	1	1	1	1	0	1	1	1	1	1	1	1	0	1	12