Table 1 Scale for quality assessment

1. Representativeness of cases

Selected from population or cancer registry

3

Selected from hospital

2

Selected from pathology archives, but without clearly defined sampling frame or with extensive inclusion/exclusion criteria

1

Not described

0

2. Source of controls

Population- based

3

Blood donors or volunteers

2

Hospital-based (cancer -free patients)

1

Not described

0

3. Pecimens of cases determining genotypes

White blood cells or normal tissues

1

Tumor tissues or exfoliated cells of tissue

0

4. Ascertainment of prostate cancer

Histopathologic confirmation

2

Diagnosis of prostate cancer by patient medical record

1

Not described

0

5. Total sample size

≧1000

3

≧400 but <1000

2

≧200 but <400

1

<200

0

6. Hardy-Weinbe rg equilibrium in controls

Hardy-Wei nberg equilibrium

1

Hardy-Wei nberg disequilibrium

0

7. Quality control of genotyping methods

Repetition of partial/total tested samples

1

Not described 0

0