The nurse is the leader of a group of developmentally disabled adults. The nurse instructs the group members to ignore another client whenever the client interrupts others who are speaking. To evaluate the progress of this intervention, the nurse should take which of the following actions?
1. Measure improvement by counting the number of times the client succeeds.
2. Measure improvement by counting the number of interruptions.
3. Assess the ability of the group to control the client's interruptions.
4. Count the number of tokens and earned privileges given for interruptions.