Question

What is primary reason that researchers strive for high rates of retention in a prospective study? A study with high retention rates…

Select one:

a. Has higher attrition rates

b. Has a lower risk of having a biased sample

c. Helps the researchers use their allotted resources and funding more effectively

d. Is able to be completed sooner

e. Has more study participants

Answer 1

Prospective study, also known as Cohort study, is the study which takes two groups, exposed to the risk factors and known exposed and the wait for occurrence of same disease in both groups and then compare. In other words, two groups are taken exposed and non exposed and we see whether the disease has developed after a particular time in both the groups and then a comparison is made. Retention means how many study participants are participating in the study process. Attrition means loss to follow up during the study process i.e. some participants may die, some may migrate or some may refuse to participate. Higher the attrition rate, lower is the retention rate. Lower the attrition rate, higher is the retention rate.

a) WRONG. As higher the retention rate, lower is the attrition rate.

b) CORRECT. As biased results can be obtained if the retention rate is low (attrition rate is high). This can be checked with help of Relative Risk. For example

c) WRONG. When the retention rate is low, participants are less and there can be better utilisation of resources.

d) WRONG. Prospective study time doesn't depend upon number of participants.

e) CORRECT. Higher the attrition rate, higher the study participants.

Both options B and E are correct. If the primary reason is asked then B will be better option to choose if you have to choose only one. Otherwise both are correct.