A pretest is to a posttest as which of the following?

Question

A) The placebo effect is to the Hawthorne effect
B) A baseline measure is to a final outcome measure
C) Blinding is to matching
D) Attrition is to a mortality threat

Answer 1

B
Feedback:
In pretest-posttest designs, data are collected both before the intervention (at baseline) and after it (outcome). The control group can undergo various conditions, including no treatment; an alternative treatment; a placebo or pseudo intervention; standard treatment at different treatment doses; or a wait-list condition. In the Hawthorne effect, various environmental conditions vary to determine their effect on worker productivity. Blinding is another means of controlling external sources of bias. Matching is deliberately making groups comparable on some extraneous variables. Longitudinal studies are typically expensive, time-consuming, and subject to the risk of attrition (loss of participants over time). Mortality is the threat that arises from attrition in groups being compared. If different kinds of people remain in the study in one group versus another, then these differences, rather than the independent variable, could account for group differences in outcomes.