Symptom scores and clinical measures in benign prostatic hyperplasia

Table 2 Summary of pooled meta-analysis results: Correlation coefficients, Fisher’s Z, and statistical significance for all three outcome pairs¹

Outcome pair	k	Total n	Pooled r	95%CI (r scale)	Fisher’s Z	SE	Z-statistic	P value	Effect size classification
IPSS-quality of life	5	705	0.713	0.557-0.820	0.893	0.135	6.62	< 0.001	Large (Cohen, 1988)
Prostate volume-IPSS	12	1,446	0.457	0.257-0.619	0.493	0.117	4.20	< 0.001	Moderate-to-Large
IPSS-post-void residual	11	2,663	0.363	0.150-0.543	0.380	0.117	3.25	0.001	Moderate

¹Effect size benchmarks per Cohen: Small r = 0.10-0.29; medium r = 0.30-0.49; large r ≥ 0.50. Back-transformation formula: R = (e^2z - 1)/(e^2z + 1).

k: Number of included studies; n: Total participants; Pooled r: Back-transformed Pearson correlation from Restricted Maximum Likelihood random-effects model; 95% confidence interval on r scale obtained by back-transforming Fisher’s Z interval bounds; SE: Standard error of pooled Fisher’s Z; Z-statistic: Wald test of H₀; IPSS: International Prostate Symptom Score; CI: Confidence interval.