Presenting results
Introduction An essential facet of statistics is the ability to summarize the important features of the analysis. We must know what to include and how to display our results in…
Errors in hypothesis testing
Making a Decision Most hypothesis tests in medical statistics compare groups of people who are exposed to a variety of experiences. We may, for example, be interested in comparing the…
Explanatory variables in statistical models
Whichever type of statistical model we choose, we have to make decisions about which explanatory variables to include in the model and the most appropriate way in which they should…
Theoretical distributions: other distributions
Some Words of Comfort Do not worry if you find the theory underlying probability distributions complex. Our experience demonstrates that you want to know only when and how to use…
Evidence-based medicine
Straus et al. 1 describe evidence-based medicine (EBM) as ‘the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients’. To practice…
Hypothesis testing
We often gather sample data in order to assess how much evidence there is against a specific hypothesis about the population. When performing descriptive analyses (Chapters 4–6) we may see…
Displaying data diagrammatically
One of the first things that you may wish to do when you have entered your data into a computer is to summarize them in some way so that you…
Error checking and outliers
In any study there is always the potential for errors to occur in a data set, either at the outset when taking measurements, or when collecting, transcribing and entering the…
