QUESTION 18 In a prospective cohort study of asthma and breastfeeding, the incid
ID: 3365303 • Letter: Q
Question
QUESTION 18
In a prospective cohort study of asthma and breastfeeding, the incidence of asthma in breastfed children was 5 per 1000 and 10 per 1000 in those not breastfed. In the same study, parents of children not breastfed were more likely to smoke than parents of breastfed children. The inference that breastfeeding protects against asthma based on this study is:
Correct
Incorrect due to failure to recognize a possible cohort effect
Incorrect because cross-sectional studies are not appropriate to determine risk of disease
Incorrect because rates and not proportions were used to compare males and females
Incorrect because there is no comparison or control group
Might be correct but we need to account for the effect of parental smoking.
A.Correct
B.Incorrect due to failure to recognize a possible cohort effect
C.Incorrect because cross-sectional studies are not appropriate to determine risk of disease
D.Incorrect because rates and not proportions were used to compare males and females
E.Incorrect because there is no comparison or control group
F.Might be correct but we need to account for the effect of parental smoking.
Explanation / Answer
Incorrect due to failure to recognize a possible cohort effect
Cohort effect refers to the situation where the observed trends do not reflect underlying biological reality but are artefacts due to sample composition. The study should be performed controlling for the parents smoking variable.
Answer: B.Incorrect due to failure to recognize a possible cohort effect