This exercise uses data from the trial that started it all, the MRC trial of streptomycin for the treatment of pulmonary tuberculosis. (MRC (1948) Streptomycin treatment of pulmonary tuberculosis. British Medical Journal 2, 769-82.) Incidently, this paper is well worth a read for anyone interested in medical research. The Library has it.
The data used in the lecture are available as an SPSS file: mrc.sav.
Question 1: Using SPSS, cross-tabulate outcome by treatment group and carry out a chi-squared test of linear association.
Check suggested answer 1.
Question 2: Create a new variable which represents alive or dead.
Check suggested answer 2.
Question 3: Carry out a chi-squared test of the null hypothesis that survival is not related to treatment. Is the test valid?
Check suggested answer 3.
Question 4: Report both tests to an appropriate number of decimal places.
Check suggested answer 4.
To Applied Biostatistics index.
To Martin Bland's M.Sc. index.
To Martin Bland's home page.
This page maintained by Martin Bland.
Last updated: 15 November, 2006.
Back to top.