R: Flu hospitalization

matched {MESS} | R Documentation

## Flu hospitalization

### Description

Researchers in a Midwestern county tracked flu cases requiring hospitalization in those residents aged 65 and older during a two-month period one winter. They matched each case with 2 controls by sex and age (150 cases, 300 controls). They used medical records to determine whether cases and controls had received a flu vaccine shot and whether they had underlying lung disease. They wanted to know whether flu vaccination prevents hospitalization for flu (severe cases of flu). Underlying lung disease is a potential confounder.

### Format

A data frame with 450 observations on the following 4 variables.

`id`

  a numeric vector

`iscase`

  a factor with levels `Control` `Case`

`vaccine`

  a factor with levels `Not` `Vaccinated`

`lung`

  a factor with levels `None` `Disease`

### Source

Modified from: Stokes, Davis, Koch (2000). "Categorical Data Analysis Using the SAS System," Chapter 10.

### Examples

    data(matched)

[Package MESS version 0.5.6 Index]