Diagnostic accuracy of diagnostic imaging for lumbar disc herniation in adults with low back pain or sciatica is unknown; a systematic review

Table 2 GRADE evidence for diagnostic accuracy of lumbar disc herniation

	Study design	Indirectness	Inconsistency	Imprecision	Publication bias	Quality
CT
9 studies	Serious limitation^a	No^b	No^c	No^d	No^e	Moderate
Myelography
8 studies	Serious limitation^a	No^b	No^c	No^d	No^e	Moderate
MRI
6 studies	Serious limitation^a	No^b	Serious limitation^c	Serious limitation^d	No^e	Very low

^aMore than 25% of participants in studies with two or more high risk of domains among four risk of bias domains
^bStudies done in a hospital setting. It was not considered as a serious applicability concern because only surgery was a reference standard
^cIt was evaluated by a correlation between logit-transformed sensitivity and logit-transformed specificity. ^dWide confidence interval of the sensitivity and specificity in more than 25% of the studies
^eThe possibility of publication bias is not excluded but it was not considered sufficient to downgrade the quality of evidence