A sample is chosen for a study on average heights and weights of adult males in a major city. The researcher uses a convenience sampling method, enacting this by going door-to-door in a neighborhood in St. Paul, Minnesota
Unbeknownst to the researcher, this neighborhood is very rich in persons of Norwegian descent, who coincidentally are the tallest Caucasians on the planet. The sampling error that occurs is a result of which of the following?
a. Random variance
b. Refusal rate
c. Systematic bias
d. Type II error
ANS: C
Systematic variation, or systematic bias, is a consequence of selecting subjects whose measurement values are different, or vary, in some specific way from the population. Because the subjects have something in common, their values tend to be similar to those of others in the sample but different in some way from those of the population as a whole. These values do not vary randomly around the population mean. Most of the variation from the mean is in the same direction; it is systematic. All the values in the sample may tend to be higher or lower than the population's mean. Random variation is the expected difference in values that occurs when one examines different subjects from the same sample. If the mean is used to describe the sample, the values of individuals in that sample will not all be exactly the same as the sample mean. Individual subjects' values vary from the value of the sample mean. The difference is random because the value of each subject is likely to vary in a different direction.
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Which independent nursing interventions would help a client develop a plan to reduce his or her genetic risk for developing a disease?
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The mother of an adolescent diagnosed with an eating disorder believes it must be genetic since the child is adopted and the mother is very weight and exercise conscious. The nurse realizes that:
1. The child must have inherited a genetic predisposition to an eating disorder. 2. The mother is setting a good example with eating and exercise. 3. The mother is obsessed with weight and exercise, and the child learned the behavior. 4. The child must have a neurotransmitter abnormality.
Nursing research is important for: a. documenting the effectiveness of interventions. b. providing a scientific knowledge base forpractice
c. validating nursing as a profession. d. all of the above.
A resident had a transurethral resection of the prostate. The person's care plan includes the fol-lowing. Which should you question?
a. No straining or sudden movements. b. Restrict fluids to 1000 mL each day. c. Measures to prevent constipation. d. No heavy lifting.