A researcher believes that therapy is more effective if patients exercise
He tells his patients that he has arranged for them to use the hospital gym, if they so desire—and that if they are interested, they will then be in the experimental group. This represents which threat to internal validity?
a. Maturation
b. Reliability of the implementation
c. History
d. Selection
ANS: D
Selection addresses the process by which subjects are chosen to take part in a study and how subjects are grouped within a study. A selection threat is more likely to occur in studies in which random assignment is not possible. In some studies, people selected for the study may differ in some important way from people not selected for the study. In other studies, the threat is due to differences in subjects selected for study groups. In this study, subjects choose to be in the experimental group because they were willing to exercise; in this way, they differ from the rest of the group—possibly they are less depressed—and this could introduce bias into the study.
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When caring for a patient, a nurse focuses on providing holistic health care by using complementary and alternative medicine (CAM). The nurse recognizes that holistic health care emphasizes which of the following? Select all that apply
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For which client who has urine incontinence problems should the nurse plan an alternative to the use of intermittent self-catheterization for urine elimination?
A. 85-year-old female client B. 60-year-old female client who is blind C. 62-year-old male client with dementia D. 48-year-old male client who has paraplegia