Assessing the acquisition of incidental information by secondary-age students with mental retardation: comparison of response prompting strategies.

The effectiveness and efficiency of four response prompting conditions (progressive time delay, progressive time delay with a descriptive consequent event, system of least prompts, and system of least prompts with a descriptive consequent event) were compared. Students with moderate to severe mental retardation were taught to read functional recipe words. Maintenance and students' acquisition of incidental information were assessed when it was (a) embedded in the prompts of the system of least prompts procedure, (b) included in the descriptive praise statements following correct performance with the progressive time delay and system of least prompts procedures, and (c) not presented. A multiple probe design across behaviors, replicated across subjects, was used. Results indicated that (a) each of the procedures produced criterion level responding: (b) efficiency data on traditional measures were roughly equal; (c) maintenance checks showed no differential effects related to the instructional condition; and (d) incidental information was acquired, although it was not directly targeted for instruction.