MEASURING DISEASE-SPECIFIC HEALTH-STATUS IN MEN WITH BENIGN PROSTATICHYPERPLASIA

In preparation for an outcomes study of benign prostatic hyperplasia ( BPH), two measures of disease-specific health status were developed to supplement a symptom score and overall health status measures. The sy mptom problem index (SPI) captures how troublesome patients find their urinary symptoms. The BPH impact index (BII) measures how much their urinary problems affect various domains of health. A prospective reval idation of the refined instruments (N = 108 BPH patients and 50 contro ls) documented that both indices had good internal consistency (Cronba ch's alpha = 0.88 and 0.79, respectively) and test-retest (r = 0.88 fo r both) reliabilities, correlated strongly with symptom scores (r = 0. 86 and 0.77), and discriminated between BPH and control subjects (rece iver-operating characteristic areas = 0.87 and 0.85, respectively). Th ese indices were nearly as responsive as symptom scores in 50 men acti vely treated for BPH, and much more responsive than a non-disease-spec ific General Health Index (GHI), a Mental Health Index (MHI), and an A ctivity Index (AI). Finally, these measures capture most of the health status significance of BPH symptoms. In linear regression models cons tructed to predict scores on the GHI, MHI, and AI, symptom scores adde d little explanatory power to the SPI and, particularly, to the BII. T hese measures help clarify how BPH affects overall health status and f unction. Such measures have an important role to play in studies of th e outcomes of treatment for BPH, and probably for other conditions tha t interfere with health status and function.