. 2018 Dec 12;2018(12):CD012669. doi: 10.1002/14651858.CD012669.pub2

Summary of findings 2. Investigation of heterogeneity.

Investigation of heterogeneity	Number of studies	Summary sensitivity (95% CI)	Summary specificity (95% CI)	Chi^2a	P value^b
Reference standard
Single CT	25	0.75 (0.63 to 0.84)	0.97 (0.93 to 0.98)	0.18 (overall)	0.9160 (overall)
CT plus laparotomy	7	0.73 (0.58 to 0.84)	0.95 (0.87 to 0.98)	0.18 (overall)	0.9160 (overall)
Target condition
Limited to free fluid/free air	22	0.78 (0.68 to 0.85)	0.97 (0.96 to 0.99)	9.10 (overall) 0.06 (sensitivity) 8.08 (specificity)	0.0106 (overall) 0.8100 (sensitivity) 0.0045 (specificity)
Free fluid/free air and organ injuries/vascular lesions	7	0.80 (0.73 to 0.85)	0.88 (0.70 to 0.96)	9.10 (overall) 0.06 (sensitivity) 8.08 (specificity)	0.0106 (overall) 0.8100 (sensitivity) 0.0045 (specificity)
Age of participant
Children	10	0.63 (0.46 to 0.77)	0.91 (0.81 to 0.96)	7.32 (overall) 54.91 (sensitivity) 19.88 (specificity)	0.0258 (overall) 0.0000 (sensitivity) 0.0000 (specificity)
Adults/mixed	24	0.78 (0.69 to 0.84)	0.97 (0.96 to 0.99)	7.32 (overall) 54.91 (sensitivity) 19.88 (specificity)	0.0258 (overall) 0.0000 (sensitivity) 0.0000 (specificity)
Type of injury
Abdominal injury	27	0.68 (0.59 to 0.75)	0.95 (0.92 to 0.97)	17.36 (overall) 13.22 (sensitivity) 5.39 (specificity)	0.0002 (overall) 0.0003 (sensitivity) 0.0202 (specificity)
Thoracic injury	4	0.96 (0.88 to 0.99)	0.99 (0.97 to 1.00)	17.36 (overall) 13.22 (sensitivity) 5.39 (specificity)	0.0002 (overall) 0.0003 (sensitivity) 0.0202 (specificity)
^aLarge values of the Chi² statistic indicate that test performance may be associated with the particular covariate. ^bP values < 0.05 indicate statistical evidence that sensitivity and/or specificity differ between the examined groups.

Abbreviations

CI: confidence interval  CT: computed tomography