Carbohydrate antigen 19-9 for differential diagnosis of pancreatic carcinoma and chronic pancreatitis

Table 4 Weighted meta-regression of the effects of study design, methodological quality and assay parameters on diagnostic accuracy of carbohydrate antigen 19-9

Covariate	Number of studies	Coefficient	RDOR (95%CI)	P value
Study design and quality
STARD ≥ 13	30	0.564	1.76 (0.14-22.68)	0.652
QUADAS ≥ 10	29	-0.666	0.51 (0.06-4.11)	0.514
Consecutive or random design	32	0.924	2.52 (0.26-24.68)	0.411
Cross-sectional design	18	-0.512	0.60 (0.28-1.28)	0.178
Blinded design	0	ND	ND	ND
Prospective design	34	ND	ND	ND
Assay method or cut-off value
RIA	17	-0.619	0.54 (0.12-2.51)	0.413
ELISA	11	-0.737	0.48 (0.10-2.26)	0.336
EIA	3	0.425	1.53 (0.29-8.14)	0.604
Cut-off of 37 U/mL	30	0.553	1.74 (0.36-8.36)	0.474
Cut-off of 100 U/mL	3	0.890	2.43 (0.72-8.26)	0.146

EIA: Enzyme immunoassay; ELISA: Enzyme-linked immunosorbent assay; ND: Not done; RIA: Radioimmunoassay; STARD: Standards for Reporting Diagnostic Accuracy; QUADAS: Quality Assessment for Studies of Diagnostic Accuracy.