Question

15 *100 sets of identical twins and 100 sets of fraternal twins are studied for rates of asthma. Results are: Identical twins: Both have disease: 4; Neither have it: 61; One has it/other does not have it: 35 Fraternal twins: Both have disease 15; Neither have it: 75; One has it/other does not have it: 10 Calculate the concordance and disconcordance rate for the identical twins and for the fraternal twins. 16 Determine the number of concordance and disconcordance cases for both the identical and for the fraternal twins. 17 Based on the data from the prior question alone, is asthma more likely to be an inherited or environmental disease? 18 What is the value of knowing if a disease is inherited or environmental?

Answer 1

	Number of Concordant Pairs	Number of Discordant Pairs	Total Number of Pairs
Identical Twins	4+61=65	35	100
Fraternal Twins	15+75=90	10	100

16)

	Number of Concordant Pairs	Number of Discordant Pairs	Total Number of Pairs
Identical Twins	4+61=65	35	100
Fraternal Twins	15+75=90	10	100

17)

Based on the data from the prior question alone, asthma is more likely to be an inherited or environmental disease.

18)

The value of knowing if a disease is inherited or environmental is Number of Concordant Pairs of identical twins and fraternal twins.

The value of knowing if a disease is inherited or environmental = 65 + 90 = 155