00:01
In a case control study evaluating the association between obesity and the risk of myocardial infection, 400 cases and 400 controls were recruited from 20 countries.
00:20
Overall 240 cases and 160 controls were identified as obese.
00:30
Right, so now odds ratio or is equals to odds of exposure in cases upon odds of exposure in controls.
01:07
Right, so this would be equals to number of obese cases is 240.
01:13
Right, number of obese cases let me just write here.
01:23
Here number of obese cases are 240, number of non -obese case is 400 minus 240 which is equals to 160.
01:49
Right, and number of obese control would be 160 and number of non -obese control would be 400 minus 160 which is equals to 240 here.
02:15
Isn't it? so now plugging in, plugging, okay simply you can plug in the values we have or is equals to 240 by 160 and this is divided by 160 by 240.
03:00
This is how we calculate the odds.
03:05
Odds is basically the ratio of happening of the event and with the non -happening of the event.
03:12
This is what you have to keep in mind...