tdata {ltable}

Tromboembolism Data.

Description

Case-control data first considered by Worcester, J (1971). The data cross-classify tromboembolism and control patients by two risk factors: oral contraceptive user and smoking. Test quantifies boosting effect of contraceptive on odds of tromboembolism.
Data used in examples of power analysis.

Usage

data(tdata)

Format

A grouped data frame with 8 rows of factors' levels combinations. Factors are: smoking status (Yes, No), contraceptive usage (Yes, No), thromboembolism status (Trombol, Control).

smoker

a character vector

contraceptive

a character vector

tromb

a character vector

Counts

a numeric vector

Details

One can use tables created by function table_f transformed with function tableToData to appropriate data.frame format with fields of factor, character, logical, and numeric classes. Or one can build data by hand with data.frame facility.

References

Worcester, J (1971). The relative odds in the 2 by 3 contingency table. American Journal of Epidemiology, 93, 145-149.

Examples

data(tdata, package="ltable")