Carlos participated in a toothbrushing skill acquisition program. When he started the program, he needed physical assistance to perform each step. After two weeks, he met all objectives and was able to complete each step independently. The program involved the use of graduated guidance, praise, and token reinforcement. In the future, the behavior analyst would like to examine which procedures made the program most effective (i.e., guidance, praise, or token reinforcement). To determine this, the behavior analyst could use a