Question

Of the 10 million residents in Los Angeles County, there 543,769 laboratory-confirmed cases (11,194 new cases)

what is the ODDS RATIO AND RELATIVE RISK

Answer 1

The odds ratio is the measure of association between an exposure and outcome.

OR=     a/c    =ad/bc

b/d

a:number of exposed cases=543769

b:number of exposed non-cases=11,194

c:number of unexposed cases:= 10million-11,194=99,88,806

d:number of unexposed non-cases=10 million-543769=94,56,231

by applying odds formula;

we get=a/c=0.05 b/d=0.001

odds ratio=0.05/0.001=50 this means that the exposed group has 50% odds of developing the infection as the unexposed group.

relative risk= risk in exposed /risk in non-exposed

relative risk=odds/1+odds=50/51=0.9