Table 2. Quality assessment of the 5 included articles in this meta-analysis.

Study	Internal Validity Criteria						External Validity Criteria						No. of items assessed as “yes” in the criteria
	IV1	IV2	IV3	IV4	IV5	IV6	EV1	EV2	EV3	EV4	EV5	EV6
Ohno [11], 2007	Yes	Yes	No	Yes	No	Yes	Yes	Yes	Yes	Yes	No	Yes	9
Plathow [10], 2008	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	10
Yi [7], 2008	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	11
Ohno [8], 2008	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	11
Lee [12], 2009	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	11

The Methodological Quality Criteria Recommended by the Cochrane Methods Working Group on Diagnostic Meta-analysis [20].

Internal Validity (IV):

1. Valid reference test (Biopsy, or imaging follow-up);

2. Blind measurement of PET/PET- CT or MRI without knowledge of reference test results;

3. Blind measurement of reference test without knowledge of results of PET/PET-CT or MRI;

4. Assessment by reference test independent of results of PET/PET-CT or MRI;

5. PET/PET-CT or MRI interpreted independently of all clinical information (Mentioned in publication);

6. Prospective study (Mentioned in publication);

External Validity (EV):

1. Spectrum of disease (Primary stage of disease);

2. Demographic information (Age and sex information given);

3. Inclusion criteria (Mentioned in publication);

4. Exclusion criteria (Mentioned in publication);

5. Avoidance of selection bias (Consecutive series of patients);

6. Standard execution of PET/PET-CT or MRI (PET/PET-CT: Type of camera, dose of 18F-fluorodeoxyglucse, time interval, reconstruction; MRI: Strength, dose of contrast medium, sequences, reconstruction);