Question

For the following questions, use the research question and context to determine the type of test required:

1. A researcher is interested in knowing whether the proportion of people who live past the age of 80 differs. She takes a sample from the local records of 100 people who had lived in each region for at least 40 years. In region X, 44% live past 80 years of age. In region Y, only 38% live past the age of 80. Is this evidence of a significant difference? * \

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

2. In a particular community it is know that about 8% of residents age 18-25 use recreational marijuana. A social services provider has run a targeted campaign to try to reduce the use of marijuana in favor of healthy endorphin-enhancing activities such as exercise. After the campaign, her team gathers data from a sample of 150 residents age 18-25 in the region, 7% of whom say they use marijuana for recreation. Is this evidence that the proportion has decreased? *

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

3. A researcher would like to investigate whether a particular drug shows adverse effects more often for those aged 45 and above versus those who are younger. They examine a sample of 400 patients who have taken the drug and been monitored by a pharmaceutical agency. For each patient they record the patient's age and examine whether the patient reported any side effects. *

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

4. A researcher would like to investigate whether a particular drug shows higher levels of adverse effects for those aged 45 and above versus those who are younger. They examine a sample of 400 patients who have taken the drug and been monitored by a pharmaceutical agency. For each patient they record the patient's age and examine the rating (on a scale 0-10) the patient reported for a possible side effect.

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

5. In a study conducted in order to investigate the relationship between blood pressure reduction and consumption of fish oil (Knapp & Fitzgerald, 1989; from Phannkuch et al. 2015), researchers randomly assigned 14 male volunteers with high blood pressure to one of two diets: a fish oil diet and a regular oil diet. Each participant’s blood pressure was measured at the beginning and end of the study, and the reduction (Pre – Post), in millimeters of mercury, was recorded. On average, the Fish oil group’s blood pressure reduction was 7.71 mm better than the Regular oil group. *

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

6. There is increasing concern about misuse of antimicrobial drugs (such as antibiotics) that are designed to kill microorganisms and stop their growth. Bacterial resistance is on the rise, and it has been found in previous studies that 30-50% of inpatient antimicrobial use is inappropriate. This raises questions about what characteristics of medical facilities are indicative of lower antibiotic use. ....In a study by Chau et al. (2016), published in a journal called Infection control and hospital epidemiology, it was found that facilities that had at least one full-time attending infectious disease specialist had significantly lower average antibiotics use. *

a.one-sample z-test

b.one-sample t-test

c.two-sample z-test

d.two-sample t-test

Answer 1

## For the following questions, use the research question and context to determine the type of test required:

Q 1.) A researcher is interested in knowing whether the proportion of people who live past the age of 80 differs. She takes a sample from the local records of 100 people who had lived in each region for at least 40 years. In region X, 44% live past 80 years of age. In region Y, only 38% live past the age of 80. Is this evidence of a significant difference?

Answer : c.two-sample z-test

Q 2)  

In a particular community it is know that about 8% of residents age 18-25 use recreational marijuana. A social services provider has run a targeted campaign to try to reduce the use of marijuana in favor of healthy endorphin-enhancing activities such as exercise. After the campaign, her team gathers data from a sample of 150 residents age 18-25 in the region, 7% of whom say they use marijuana for recreation. Is this evidence that the proportion has decreased? *

Answer : a.one-sample z-test

Q 3)

A researcher would like to investigate whether a particular drug shows adverse effects more often for those aged 45 and above versus those who are younger. They examine a sample of 400 patients who have taken the drug and been monitored by a pharmaceutical agency. For each patient they record the patient's age and examine whether the patient reported any side effects. *

Answer c.two-sample z-test

Q ) 4.

A researcher would like to investigate whether a particular drug shows higher levels of adverse effects for those aged 45 and above versus those who are younger. They examine a sample of 400 patients who have taken the drug and been monitored by a pharmaceutical agency. For each patient they record the patient's age and examine the rating (on a scale 0-10) the patient reported for a possible side effect.

Answer : c.two-sample z-test

Q 5)

In a study conducted in order to investigate the relationship between blood pressure reduction and consumption of fish oil (Knapp & Fitzgerald, 1989; from Phannkuch et al. 2015), researchers randomly assigned 14 male volunteers with high blood pressure to one of two diets: a fish oil diet and a regular oil diet. Each participant’s blood pressure was measured at the beginning and end of the study, and the reduction (Pre – Post), in millimeters of mercury, was recorded. On average, the Fish oil group’s blood pressure reduction was 7.71 mm better than the Regular oil group. *

Answer : d.two-sample t-test ( paired t test)

Q 6)

There is increasing concern about misuse of antimicrobial drugs (such as antibiotics) that are designed to kill microorganisms and stop their growth. Bacterial resistance is on the rise, and it has been found in previous studies that 30-50% of inpatient antimicrobial use is inappropriate. This raises questions about what characteristics of medical facilities are indicative of lower antibiotic use. ....In a study by Chau et al. (2016), published in a journal called Infection control and hospital epidemiology, it was found that facilities that had at least one full-time attending infectious disease specialist had significantly lower average antibiotics use. *

Answer : b.one-sample t-test