Table 5.

Comparison of reports that fulfilled each OQAQ component pre-QUOROM and post-QUOROM

OQAQ question	Pre-QUOROM (n (%))	Post-QUOROM (n (%))	p-value
Were the search methods used to find evidence on the primary question(s) stated	52 (88.1)	79 (98.8)	0.010
Was the search for evidence reasonably comprehensive?	14 (23.7)	35 (43.8)	0.019
Were the criteria used for deciding which studies to include in the overview reported?	44 (74.6)	74 (92.5)	0.007
Was bias in the selection of studies avoided?	15 (25.4)	34 (42.5)	0.048
Were the criteria used for assessing the validity of the included studies reported?	33 (55.9)	60 (75.0)	0.028
Was the validity of all the studies referred to in the text assessed using appropriate criteria?	23 (39.0)	42 (52.5)	0.13
Were the methods used to combine the findings of the relevant (to reach a conclusion) reported?	40 (67.8)	70 (87.5)	0.006
Were the findings of the relevant studies combined appropriately relative to the primary question of the overview?	29 (49.2)	59 (73.8)	0.004
Were the conclusions made by the author(s) supported by the data and/or analysis reported in the overview?	35 (59.3)	69 (86.3)0	<0.0005

Data expressed as the number of reports that scored 'yes' for each component (percent). P-values derived from Fisher's exact test. OQAQ, Overview Quality Assessment Questionnaire; QUOROM, Quality of Reporting of Meta-analyses.