Answer to Question #90537 in Psychology for M

Question

Thirtypeople contact her. She tells them that treatment is on a first-come first-served basis.
So, the first 15 people who make an appointment with her go into the treatment
condition; the last 15 people go into the wait list control condition [this means, they
will still get the treatment, but first they have to act as controls]. The researcher
measures everyone's level of depression at baseline; then she runs the intervention with
the treatment group; then she measures everyone's level of depression again. She finds
that the treatment has a strong significant effect; participants who experienced the
treatment reported significantly lower levels of depression afterwards compared to
those in the wait list control condition. What sort of design was this, and what methodological mistake did the researcher make?
a. Longitudinal design; no testing of participants three months after treatment.
b. Quasi-experimental design; no testing of participants three months after
treatment.

Answer 1

B. Quasi-experimental design; no testing of participants three months after treatment