The German version of the Expanded Prostate Cancer Index Composite (EPIC): translation, validation and minimal important difference estimation

Table 6 Anchor- and distribution-based estimates of the minimal important difference for the EPIC summary domains (n = 92^a)

Anchor based approaches
	EPIC Urinary domain	EPIC Bowel domain	EPIC Sexual domain	EPIC hormonal domain
Global rating of health state change	11.4	2.6	13	6.5
Distribution based approaches^c
SEM^a	5.3	3.9	7.1	5.7
Cohen’s effect size	9.4	5.5	11.5	6.5
Empirical rule effect size	9.0	5.3	11.0	6.2
0.5 times SD	6.0	3.9	10.2	5.7

Abbreviations: EPIC Expanded Prostate Cancer Index Composite, SEM Standard error of measurement
^aMissing values: 0–2; SEM approach based on the test-retest subsample of 44 participants
^bAveraged difference in mean change score in EPIC domains between those who rated their health state as “worsened” and “remained the same”
^cSEM = SD at baseline*square root[1- intraclass correlation coefficient]); Cohen’s effect size = 0.5*SD of change score; empirical rule effect size = 0.08*6*SD of change score); 0.5*SD at baseline

ISSN: 1477-7525