Jae Mann Song, et al. sion. The inclusion criteria for this meta-analysis were as follows. 1) Patients who had lower uri- nary symptoms of prostate cancer or benign pros- tate hyperplasia. These symptoms were mainly disturbances of urination, hematuria, etc. 2) The diagnostic PSA, DRE and TRUS tests for the clinical diagnosis of prostate cancer must have been simultaneously compared in the each article. 3) The studies included biopsy results as a refer- ence standard to confirm prostate cancer. 4) The articles must have contained sufficient or available numeric information such as a 2 × 2 contingency data table or the patients' outcome data, e.g., data in terms of sensitivity (Sn), specificity (Sp), and percent agreement of the PSA, DRE, and TRUS testing. Of the 44 articles that were evaluated at the final stage, only 13 of the studies that com- pared PSA, DRE and TRUS met these inclusion criteria, and so these were selected for the meta- analysis. For the quantitative meta-analysis process, the Hasselblad method23,24 was utilized with the SAS systemTM by Song H.H.25 To integrate results, the sensitivity and specificity on each study's outcome data were used as effect sizes, and the d̅value and 95% confidence interval (CI) of d̅were estimated. Concerning the fixed effects model, additional homogeneity tests were conducted. Each the estimates of d̅,the variance of d̅,95% CI of d̅and homogeneity test were produced as follows. Estimate of d : d= 3[loge(Sn/(1-Sn))+loge(Sp/(1-Sp))]/π (Sn; sensitivity, Sp; specificity) d= 3[loge(A+1/2)+loge(D+1/2)-loge(B+1/2)- loge(C+1/2)]/π (A; true positive, B; false positive, C; false negative, D; true negative in the 2×2 con- tingency table) Variance of d: var(d) 3[1/(A+1/2)+1/(B+1/2)+1/(C+1/2)+ 1/(D+1/2)]/π2 The combining estimates of effectiveness (d̅)in m studies are usually given by the weighted mean: d̅=(Σωjdj)/(Σωj), (j=1, 2, 3, ---, m) where ωj=1/var (dj) Variance of the combined estimate: Var (d̅)=1/(Σωj) 95% CI for the average effect size: d̅±1.96 Var (d̅) Yonsei Med J Vol. 46, No. 3, 2005 Homogeneity test: Q=Σωj(dj-d̅)2 ~ χ2(m-1) RESULTS The general characteristics of the 13 studies26-38 are summarized in Table 1. All the studies were published after 1991. A total of 2,029 men with lower urinary symptoms had PSA and DRE performed. Among those men, TRUS were per- formed on 1,947 of them. All the subjects had TRUS guided transurethral biopsy or transure- thral prostatectomy27,36 for the pathological diag- nosis of prostate cancer. Of the 2,029 symptomatic men, 516 of them (25.4%) were pathologically dia- gnosed as having prostate cancer, with each study having a wide range (13.5-41.5%). The others were diagnosed with benign prostate hyperplasia (72.9%) and chronic prostatitis etc. (1.7%). The mean age of the patients was 67.8 years and the age of these patients ranged from 30 to 93 years old. The authors of all 13 studies were mostly urologists and only two studies35,37 were coopera- tively conducted by urologists and a diagnostic radiologist or pathologist. The sensitivity, specificity and percent agree- ment of prostate-specific antigens as the diag- nostic parameters of prostate cancer in all 13 studies are listed in Table 2. When the PSA crite- ria were greater than 4 ng/mL (PSA4), the overall sensitivity was 91.3% with a range of 73.3% to 100.0%, and the overall specificity was 35.9% with a range of 13.1% to 88.9%, and each of the values were scattered widely among the studies. In addition, the overall percent agreement of PSA4 with the diagnosis was 50.1% with a range of 32.1% to 84.3%. With a PSA > 10 ng/mL (PSA10), the overall sensitivity was 77.3% with a range of 53.3% to 100.0%, and the overall specificity was 67.5% with a range of 37.7% to 100.0%. In addi- tion, the overall percent agreement of PSA10 with the diagnosis was 69.9% with a range of 50.6% to 86.3%. The data on sensitivity, specificity and percent agreement for the digital rectal examination and transrectal ultrasonography for detecting prostate cancer are shown in Table 3 and Table 4. The overall sensitivity, specificity and percent agree- ment (range) for DRE were 68.4% (56.7% to 88.9%),