Users' Guides to the Medical Literature: X. How to Use an Article Reporting Variations in the Outcomes of Health Services

CASE SCENARIO Your patient, a 78-year-old retired internist, has been complaining of increasing symptoms of benign prostatic hyperplasia. He has long-standing hypertension and coronary artery disease, with remote anterolateral myocardial infarction and bypass surgery 10 years ago. His left ventricular ejection fraction was recently documented at 20%, and he has been started on an angiotensin-converting enzyme inhibitor. Rectal examination confirms a moderately enlarged prostate, without irregularities, nodularity, or tenderness. As you discuss management options, your patient insists that transurethral prostate surgery is dangerous and that international studies of thousands of patients have proved that, as he puts it, "old-fashioned open prostatectomy is safer than that keyhole surgery." You prescribe a trial of an α-blocker, terazosin, and arrange to see him again. However, the retired internist sounds so convinced that you also resolve to look into the evidence about the two forms of prostatectomy.THE SEARCH Later, you sit down in