Question

Epidemiology

Question 7

When an individual has the disease then they were definitely exposed to the Factor A but if exposed to Factor A this disease sometimes develops. Factor A is:

		A necessary, but not sufficient, cause
		A sufficient, but not necessary, cause
		A necessary and sufficient cause
		Neither necessary not sufficient

Question 8

When an individual is exposed to Factor A this disease always develops and if there is an absence of Factor A the disease will not develop. Factor A is:

		A necessary, but not sufficient, cause
		A sufficient, but not necessary, cause
		A necessary and sufficient cause
		Neither necessary not sufficient Question 9 Why are controls needed in a case-control study? They may be followed for development of the outcome of interest They are less likely to have recall bias issues They increase the size of the study so that risk estimates are significant They do not have the outcome of interest and allow for estimation of exposure frequency among those without the disease They do not have the exposure of interest and allow for the estimation of disease frequency among the unexposed

Answer 1

Q.7. Correct option is A as in this condition

•Without factor the disease never develops hence it is necessary and with factor, a disease will not develop in sure shot thats its not sufficient means other other factors ared required

Q.8 option C is correct as in this condition the factor A is necessary and sufficient cause to develop the disease in the absence of this factor there will be no prevalence signs of the disease and there is no any requirement of the other factors as the factor A is sufficient to cause this disease

Q.9. Option E is correct as in controls they are not exposed to the disease and they are used compare the outcomes of interests in the exposed one