The week before July 1, 1988, the lead author sent to all FP residents a memorandum explaining the study, presenting the literature in support of the HDPI, and outlining the dimensions of the problem of inappropriate CCU utilization.
A graduate research assistant abstracted each record for demographic information, admission and discharge diagnoses, CCU utilization, peak creatine kinase (CK) level and MB fraction, complications (sustained ventricular arrhythmias, high-grade block, congestive failure, and reinfarction), and HDPI score.
Other independent variables in the model were age, patient sex, physician sex, and HDPI score.
To elucidate this, we analyzed CCU utilization in a logistic regression model as a function of time, using as independent variables patient age, sex, HDPI score, and dummy variables for periods 1 through 4.
Patients did not differ significantly over the periods by HDPI score (F(3) = 1.
The seven factors comprising the HDPI are listed in Table 1.
A graduate student trained in medical record abstraction and application of the HDPI reviewed the medical records of all patients admitted to the study.
i] takes values of 1 or 2 for dichotomous variables, 0--1 continuously for HDPI score, and the scalar quantity of years for age.
Logistic regression was also performed for the study variables with a dependent variable of MI, to verify that the HDPI yielded the expected predictive accuracy, and to confirm the findings of the univariate analyses controlling for each of the other variables.
Women and men did not differ in probability of ischemia as measured by the HDPI (0.