A cross classified table with observational data from a Danish heart clinic. The response variable is CAD (coronary artery disease, some times called heart attack).

data(cad1)

Format

A data frame with 236 observations on the following 14 variables.

Sex

Sex; a factor with levels Female Male

AngPec

Angina pectoris (chest pain attacks); a factor with levels Atypical None Typical

AMI

Acute myocardic infarct; a factor with levels Definite NotCertain

QWave

A reading from an electrocardiogram; a factor with levels No Yes; Yes means pathological and is a sign of previous myocardial infarction.

QWavecode

a factor with levels Nonusable Usable. An assesment of whether QWave is reliable.

STcode

a factor with levels Nonusable Usable. An assesment of whether STchange is reliable.

STchange

A reading from an electrocardiogram; a factor with levels No Yes. An STchange indicates a blockage of the coronary artery.

SuffHeartF

Sufficient heart frequency; a factor with levels No, Yes

Hypertrophi

a factor with levels No, Yes. Hypertrophy refers to an increased size of the heart muscle due to exercise.

Hyperchol

a factor with levels No Yes. Hypercholesterolemia, also called high cholesterol, is the presence of high levels of cholesterol in the blood.

Smoker

Is the patient a smoker; a factor with levels No, Yes.

Inherit

Hereditary predispositions for CAD; a factor with levels No, Yes.

Heartfail

Previous heart failures; a factor with levels No Yes

CAD

Coronary Artery Disease; a factor with levels No Yes

. CAD refers to a reduction of blood flow to the heart muscle (commonly known as a heart attack). The diagnosis made from biopsies.

Details

Notice that data are collected at a heart clinic, so data do not represent the population, but are conditional on patients having ended up at the clinic.

  • cad1: Complete dataset, 236 cases.

  • cad2: Incomplete dataset, 67 cases. Information on (some of) the variables 'Hyperchol', 'Smoker' and 'Inherit' is missing.

References

Hansen, J. F. (1980). The clinical diagnoisis of ichaeme heart disease du to coronary artery disease. Danish Medical Bulletin

Højsgaard, Søren and Thiesson, Bo (1995). BIFROST - Block recursive models Induced From Relevant knowledge, Observations and Statistical Techniques. Computational Statistics and Data Analysis, vol. 19, p. 155-175

Examples


data(cad1)
## maybe str(cad1) ; plot(cad1) ...