Pitfalls in evaluating the impact of coronary care units on mortality from myocardial infarctions.
D000368:Aged; D003325:Coronary Care Units; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008396:Maryland; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*