An investigator studied the effect of music therapy on pain ratings among children following a tonsillectomy. She wanted to determine if music therapy was more effective among certain ages of children as compared to other ages. She divided her sample into the following age groups: infants, toddlers, preschool-aged children, school-aged children, and adolescents. In this study, the age groups are:

Researchers distributed two questionnaires in an endocrine clinic waiting room. One questionnaire measured the amount of social support the patient reported receiving and the other question measured the patients’ feelings of competence in self-managing their diabetes. After analyzing the data, they found that patients who reported high levels of social support also reported high levels of competence and patients who reported low levels of social support also reported low levels of competence. This describes:

Which statement about measurements is FALSE?

Which of the following is an example of a null hypothesis?

A researcher conducted a study examining hearing tests of 100 children. She reported that subjects ranged from 3-9 years old (mean = 6 years, SD = 1 year). How many standard deviations below the mean was the youngest participant?

Using volunteers as subjects in a study,

An investigator collects data that are normally distributed with a mean score of 50 and a standard deviation of 10. Approximately 95% of the scores would fall between which two numbers?

A researcher wants to study the effect of vitamin D intake on muscle strength. She randomly assigns subjects to either an experimental group who receive Vitamin D supplementation or a control group who are given a placebo pill that does not contain any active ingredient. She measures subjects’ muscle strength before beginning supplementation and then 6 months after the subjects had been receiving daily supplementation. This is an example of:

Mirbagher-Ajorpaz and colleagues (2011) hypothesized that an acupressure intervention would decrease dysmenorrheal among female medical science students. They divided the sample of female medical science students into two groups – one group received the acupressure intervention and the other group did not receive any intervention. What statistical test, from the following list, would be the most appropriate to use to compare the mean dysmenorrhea scores of the intervention and control groups?

Which of the following statements about informed consent is FALSE?