Question 2: The authors say that the overall odds ratio for regular phone use was 0.94. What is an odds ratio?
The odds of a subject having a characteristic is the ratio of the number of such subjects with the characteristic to the number without the characteristic. The odds of being a mobile phone user is the number of mobile phone users divided by the number who do not use a mobile phone. The odds ratio is the odds of phone use for cases divided by the odds of phone use for controls.
For every non -user of mobile phones, there are 0.94 times as many mobile phone users among cases as there are among controls. Cases were slightly less likely to be mobile phone users than were controls.
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Last updated: 31 Jul, 2006.