Kravitz RL, Laouri M.
Measuring and averting underuse of necessary cardiac procedures: a summary of results and future directions.
Jt Comm J Qual Improv 1997;23(5):268-76.

The purpose of this study was to examine the extent of underuse of coronary angiography and coronary artery revascularization and the factors associated with this underuse. The study was divided into the analysis of two procedures – angiography and revascularization.

For the coronary angiography analysis, patients who met criteria for “necessity of coronary angiography” (based on age, symptoms, medications, and diagnostic tests) from four Los Angeles area hospitals in 1990 and 1991 were included. Among the 352 people selected, the telephone survey response rate was 69%. Among the patients meeting criteria, 56% received the procedure within twelve months. For the revascularization analysis, patients who met criteria for “necessity of coronary revascularization” were included. Among the 671 people selected, the telephone survey response rate was 64%. Among 506 patients meeting criteria, 75% underwent coronary-artery bypass surgery (CABG) or percutaneous transluminal coronary angioplasty (PCTA) within two months.

While there were several clinical factors associated with greater likelihood of receiving the necessary procedure, gender, race and hospital type were associated with underuse. With regard to race, blacks were less likely to receive necessary CABG surgery and PTCA. This finding was also reported in two previous papers (Kahan, JP et al. Measuring the necessity of medial procedures. Medical Care 1994;32:357-365; Kassirer JP. Managed care and the morality of the medical marketplace. New Engl J Med 1995;333:50-52.)

Although the decision to recommend a coronary revascularization procedure is nearly always made by a cardiovascular specialist, referral for angiography is usually left in the hands of the primary care or emergency department physician. Thus, the authors tested whether patients who received care from a cardiologist/cardiology clinic would be more likely to receive necessary angiography. The study found this to be the case (adjusted probability was 74% versus 44% having the procedure). The authors also demonstrated that patients who had necessary revascularization had significantly better survival than those who did not, a finding that validated their necessity criteria.

This paper describes twelve criteria proposed by RAND to measure use of a procedure. These criteria apply to a range of procedures and consider necessity of the procedure, medical record review, patient refusals, and sociodemographic and clinical trends.