Table 1 Characteristics of the excluded studies

Block 2005

Patients: HCC vs. Healthy

Tests: immunoblot assay for GP73, AFP not measured.

Outcomes: no usable data.

Mao 2008

Suspected overlapped study population with Mao 2010

Chen 2011

Suspected overlapped study population with Mao 2010.

Li 2009a

Patients: HCC vs. cholangiocellular carcinoma

Tests: GP73, AFP and VEGF expression in tumor, tumor-adjacent and normal liver specimens by immunohistochemistry.

Outcomes: no usable data.

Riener 2009a

Patients: HCC vs. (healthy and viral hepatitis)

Tests: methods for GP73and AFP test not cleared reported

Outcomes: no usable data.

Riener 2009b

Patients: HCC vs. (chronic HCV infection, bile duct carcinoma and healthy)

Test: sera GOLPH2 detection using ELISA, AFP not tested.

Outcomes: no usable data.

Stenner 2009

Patients: HCC vs. (HCV, bile duct carcinoma and healthy)

Tests: sera GOLPH2 levels by ELISA, unclear whether AFP tested or not.

Abstract; no clear data reported.

Li 2009b

Patients: HCC vs. (cirrhosis and healthy)

Tests: methods for serum GOLPH2 and AFP not reported.

Letter; no usable data.

Yamamoto 2009

Patients: HCC

Tests: serum GP73 autoantigen/autoantibody and AFP measured

Abstract, no usable data.

Yamamoto 2010

Patients: HCC

Tests: serum GP 73 autoantigen and autoantibody measured by ELISA.

Outcomes: sensitivity/specificity at cutoff points was not calculated.

Tan 2009

Patients: HCC vs. (liver disease without HCC and healthy)

Tests: serum GOLPH2 levels by ELISA, AFP not measured.

Outcomes: sensitivity, specificity and cut off value were available, but AFP levels were not tested.

Gu 2009

Patients: HCC vs. cirrhosis

Tests: GP73 by ELISA, AFP not tested.

Outcomes: sensitivity, specificity and cut off value were available, but AFP levels were not tested.