In a Multiple-Baseline Design Using Two Participants, What Should a Researcher

Multiple Choice

In a multiple-baseline design using two participants, what should a researcher do to ensure that any change in behavior is due to the treatment and not an outside factor?

A) Revert back to the baseline for one of the participants, but not the other
B) Introduce the treatment at a different time for each participant
C) Introduce the treatment immediately for both participants
D) Administer a questionnaire to ask participants about outside influences