Table 1 Explanatory variables used in the multivariate analysis

Patient-related clinical indicators

FEMALE

Dummy variable taking the value '1' for female patients

AGEGRP0-AGEGRP5

One dummy variable for each age group (where AGEGRP0 includes patients aged 65–69 and AGEGRP5 patients older than 90)

YR93-YR98

One dummy variable for each year

DIST_CATH

Distance from the patient's area geographical center to the area geographical center of the nearest hospital offering cardiac CATH.

DIST_CARD

Distance from the patient's area geographical center to the area geographical center of the nearest hospital offering CABG or PCI.

COCHF

Congestive heart failure

CARD

Cardiac dysrhythmias

PULED

Pulmonary edema

SHOCK

Shock

CRF

Chronic renal failure

ARF

Acute renal failure

DIABET

Diabetes

MAL

Malignancy

CERVAS

Cerebrovascular disease

Area-based socioeconomic indicators

INC

Median family income in ZIP code area of residence.

INC_Q1

The patient's area belongs to the lowest median income quintile in country X

INC_Q2

The patient's area belongs to the 2^nd median income quintile in country X

INC_Q3

The patient's area belongs to the 3^rd median income quintile in country X

INC_Q4

The patient's area belongs to the 4^th median income quintile in country X

INC_Q5

The patient's area belongs to the highest median income quintile in country X