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Exercise

Factorial designs: exploring data

A trial was designed to assess whether supplementing with glutamine or selenium, or both affected the odds of infections in critically ill patients (Andrews et al, BMJ. 2011 Mar 17;342). A factorial, randomized design was used. The data is stored in fact.data.

First, we will explore the infection rates in the two supplements. The dplyr library has been preloaded for this session.

Instructions
100 XP
  • Use the head() function to explore the dataset.
  • Display the infection numbers by glutamine and selenium status.
  • Display the numbers and proportions with infections for each of the supplements, i.e ignoring whether the other was administered.