Question

You are designing an experiment to determine the effectiveness of a new treatment.

You suspect that age is a possible confounding variable.

In designing your study, which one of the following strategies is not useful for avoiding this possible confounding effect?

Answers:	a. randomisation (assigning interventions at random to the subjects, irrespective of age)
	b. blocking/stratification (group subjects into age categories such as 20-29, 30-39, etc. Then use age group as a blocking variable)
	c. statistical adjustment (allowing for the effect of age on the response variable)
	d. controlling (specifying) how much of the treatment is given to a subject of a particular age

a,c are wrong anwers

Answer 1