In a study about help to quit smoking,one group of participants received a single supportive phone call 10 days after attending a program on strategies to resist the urge to smoke.A second group received a weekly supportive phone call for 6 weeks after attending the same program,and a third group received no supportive phone calls after attending the program.What property of experimental research did the researcher employ in this study?

Question

Quizplus · Accepted Answer

The researcher manipulated the intervention dose by varying the frequency of supportive phone calls among the groups, which directly tests the effect of this variable on the outcome (help to quit smoking).

In a Study About Help to Quit Smoking,one Group of Participants