5. Why do they say that employees who retired at 55 and were still alive at 65 had significantly higher mortality than those who retired at 65, when no P value is given?
The difference is significant at the 0.05 level because the 95% confidence interval for the hazard ratio, which is 1.09 to 1.73, does not include 1.00. This is the value the hazard ratio for the population would have if the null hypothesis were true.
Back to question.
Back to Clinical Biostatistics index.
To Martin Bland's home page.
This page maintained by Martin Bland.
Last updated: 31 July, 2006.
Back to top.