R: Epilepsy Data

epilepsy {HSAUR} | R Documentation

## Epilepsy Data

### Description

A randomised clinical trial investigating the effect of an anti-epileptic drug.

### Usage

    data("epilepsy")

### Format

A data frame with 236 observations on the following 6 variables.

`treatment`

  the treatment group, a factor with levels `placebo` and `Progabide`.

`base`

  the number of seizures before the trial.

`age`

  the age of the patient.

`seizure.rate`

  the number of seizures (response variable).

`period`

  treatment period, an ordered factor with levels `1` to `4`.

`subject`

  the patient ID, a factor with levels `1` to `59`.

### Details

In this clinical trial, 59 patients suffering from epilepsy were randomized to groups receiving either the anti-epileptic drug Progabide or a placebo in addition to standard chemotherapy. The numbers of seizures suffered in each of four, two-week periods were recorded for each patient along with a baseline seizure count for the 8 weeks prior to being randomized to treatment and age. The main question of interest is whether taking progabide reduced the number of epileptic seizures compared with placebo.

### Source

P. F. Thall and S. C. Vail (1990), Some covariance models for longitudinal count data with overdispersion. Biometrics, 46, 657–671.

### Examples

      data("epilepsy", package = "HSAUR")
      library(lattice)
      dotplot(I(seizure.rate / base) ~ period | subject, data = epilepsy,
              subset = treatment == "Progabide")
      dotplot(I(seizure.rate / base) ~ period | subject, data = epilepsy,
              subset = treatment == "Progabide")

[Package HSAUR version 1.3-9 Index]