A casecontrol study was performed to study the relationship

A case-control study was performed to study the relationship between the source of meat consumed during the prenatal period and congenital malformations. Case mothers were those with malformed infants in a registry in Africa between 1951 and 1979. Controls were individually matched by hospital, maternal age (± 2 years), and date of birth (± 1 month). The suspected causal agent was anthrax.

Which non-parametric test would be most appropriate to use in this situation? Why?

What would the null and alternative hypotheses be in this situation?

Solution

The most appropriate non-parametric test would be the odds ratio or the relative risk ratio (there might be other non-parametric tests as well that can serve the purpose)

This can be used to check if the exposure to anthrax or the causal agent is responsible in the congenital malformations or not. A chi-squared test value can also be used if the proportion of expected cases is known.

Null Hypothesis : Anthrax exposure and congenital malformations are not correlated

Alternate Hypothesis : Anthrax exposure is responsible for the higher amount of congenital malformations

Hope this helps,