Deck 9: Student T-Test

Question 1

A researcher wishes to determine if nurses in California have higher average vitamin D levels than nurses in New York. What would be an appropriate test to use?

A) Chi-Square
B) T-test for dependent samples
C) T-test for independent samples
D) Pearson's Correlation Coefficient

Answer 1

C

Question 2

A professor wishes to determine if there is a difference between the average test grades of her students who use the resources available to them with those students who don't use the resources. The Alpha is 0.05 and the P-value is 0.03. She should conclude:

A) Reject the null hypothesis because there is a statistically significant relationship between nursing students' grades and their use of available resources.
B) Fail to reject the null hypothesis. There is not a relationship between nurses' grades and using available resources.
C) Reject the null hypothesis. Nursing students are more likely to use the resources available.
D) Fail to reject the null. The relationship is not clinically significant.

Answer 2

A

Question 3

Researchers study the relationship between interpersonal violence and health in college age women. The researchers planned to examine the average score on a psychological distress scale and compare the score for abused versus non abused women. What would be an appropriate test to consider?

A) Dependent t test
B) McNemar's test
C) chi-square test
D) t test for independent groups

Answer 3

D

Question 4

Researchers studied symptom distress and palliative care designation among a sample of 710 hospitalized patients. Controlling for age, they used a t-test to compare average distress from nausea scores in men and women. Lower scores indicated less distress from nausea. They report men had an average score of 1.02 and woman had an average score of 1.79. Which statement is correct?

A) Men had significantly less distress from nausea.
B) Men had half as much distress from nausea as woman but we can not determine if this is a significant difference.
C) Men had less distress from nausea on average than women but we can not determine if this is a significant difference.
D) There is a positive correlation between distress from nausea and gender.

Question 5

Researchers studied nausea among a sample of hospitalized patients. They used a t-test to compare average nausea scores in men and women. They report men had an average score of 1.02 and woman had an average score of 1.79. (p<0.001) Which statement is correct?

A) Men had significantly less nausea.
B) Men had 79% less nausea but we can not determine if this is a significant relationship.
C) A paired t-test was appropriate because the patients were all from the same hospital.
D) There is a significant positive correlation between nausea and gender.

Question 6

A random sample of nurses were involved in a hand washing study at a local hospital to determine if the average residual bacterial count on hands was different for day or night nurses. The study involves an alpha of 0.10 and finds a p value of 0.12. What should the researcher conclude?

A) Night nurses have a higher average residual bacterial count on their hands.
B) There is a statistically significant difference in the residual bacterial count found on the hands of day and night nurses.
C) This is a type II error
D) There is NOT a statistically significant difference in the residual bacterial count found on the hands of day and night nurses.

Question 7

A nurse researcher wishes to determine if there is a difference in the mean IQ level for a sample of brothers and a sample of their sisters. What would be an appropriate test?

A) repeat measures t-test
B) t-test for independent groups
C) repeat measures ANOVA
D) t-test for dependent groups

Question 8

A study with 890 subjects examines if day or night nurses assess more wounds on average during an eight hour shift. Each time a day or night nurses assesses a wound it is recorded in their smart phone app. The data is then compiled and analyzed. An appropriate test to use would be:

A) independent t-test
B) dependent t-test
C) Chi-square
D) ANOVA

Question 9

A researcher wishes to determine if there is a difference in the average flexibility test score for female athletes and the average flexibility test score for their best friends. An appropriate test to utilize would be:

A) independent t-test
B) dependent t-test
C) Chi-square
D) ANOVA

Question 10

A researcher utilizes a t-test to compare the average amount of beta-lactamase produced by two different types of bacteria. The Levene's test for equality of variances has a p value of 0.09. You know this means:

A) You should report the t-test results associated with assuming equal variances.
B) You should report the t-test results associated with NOT assuming equal variances.
C) The t-test is not significant so you should fail to reject the null hypothesis.
D) The t-test is statistically significant so you should reject the null hypothesis.

Question 11

A researcher utilizes a t-test to compare the average amount of beta-lactamase produced by two different types of bacteria. The Levene's test for equality of variances has a p value of 0.01. You know this means:

A) You should report the t-test results associated with assuming equal variances.
B) You should report the t-test results associated with NOT assuming equal variances.
C) The t-test is not significant so you should fail to reject the null hypothesis.
D) The t-test is statistically significant so you should reject the null hypothesis.

Question 12

A researcher studies the relationship between taking aminoglycosides and muscle strength in a random sample of patients who take aminoglycosides and a random sample of patients who do not take aminoglycosides. An average strength score is calculated for each participant. To determine if there is a statistically significant difference in the average strength score an independent t-test is utilized. The researchers report that taking aminoglycosides is associated with a lower average strength score (t=1.984, p=0.025). You know this means:

A) A type I error was made
B) Equal variances was not assumed.
C) The Levene's test was insignificant
D) There is a statistically significant difference in the average strength score between the two groups.

Question 13

Researchers wanting to assess skin irritation associated with a new sunscreen developed for those with photosensitivity. They randomly sample 240 men with a history of photosensitivity and 240 men without a history of photosensitivity and ask them to apply the cream and report the level of skin irritation they experience after spending 20 minutes in the sun using a scale of 0-10. The average skin irritation score for the group with a history photosensitivity was 1.2 and the average skin irritation score for the group without a history of photosensitivity was 1.4. The Levene's test for equality of variances had a p value of 0.08. You know this means:

A) The researchers should report the t test results assuming equal variances.
B) The researchers should report the t test results NOT assuming equal variances.
C) The researchers should reject the null hypothesis and report there is a difference in the average skin irritation score.
D) The researchers should fail to reject the null hypothesis and conclude there is NOT a difference in the average skin irritation score.

Question 14

Your study of the use of compression stockings for post-surgical DVT prophylaxis utilizes an independent t-test and reports a p value of 0.02. The study has an alpha of 0.05, a beta of 0.08 and a sample size of 567 patients. What do you conclude?

A) The results are clinically significant
B) The results are not statistically significant
C) A type II error is being made
D) The results are statistically significant.

Question 15

When a researcher is examining the association between gender (male/femal

A) Pearson correlation coefficient
B) Chi-square
C) Independent t-test
D) Dependent t-test
E) and high school grade point average, what test would be appropriate?

Question 16

You have two randomly selected groups enrolled in two different weight loss programs and you want to compare the average number of pounds lost. What test would be appropriate?

A) Independent T-test
B) ANOVA
C) Pearson's Correlation Coefficient
D) Chi-square

Question 17

Researchers want to conduct an independent t-test to compare subjects for whom English is a primary language and non-native English speakers. In order to do so the outcome or dependent variable needs to be what level:

A) Interval or ratio
B) Nominal or ordinal
C) Interval or ordinal
D) Nominal or ratio

Question 18

You are trying to determine if there is a significant difference in the mean age between patients who have developed a nosocomial infection in your hospital and those who have not. Use your SPSS output (above) to determine what t value you should report.

A) t=0.548
B) t=0.487
C) unable to determine
D) t=4.166

Question 19

You are trying to determine if there is a significant difference in the mean age between patients who have developed a nosocomial infection in your hospital and those who have not. Your results indicate t=0.487, p=0.632. You conclude:

A) Levene's test was insignificant.
B) There is a statistically significant difference in the mean age of those who develop a nosocomial infection and those who do not.
C) There is NOT a statistically significant difference in the mean age of those who develop a nosocomial infection and those who do not.
D) Nosocomial infections are more likely to occur in those who are over age 48.7 years.

Question 20

You are trying to determine if there is a significant difference in the mean age between patients who have developed a nosocomial infection in your hospital (N=312) and those who have not (N=4,673). What would be an appropriate test to use?

A) Chi-square
B) McNemar's test
C) t-test for dependent groups
D) t-test for independent groups