Biostatistics Midterm 522 Rush
Questions with Accurate Answers
6 Core Epidemiological Functions correct answer Surveillance
Field Investigations
Analytical Studies
Evaluation
*Linkages*
Policy
A *non-parametric test* should be used when ANY of the following conditions are
present: correct answer 1. Measured at *Nominal or Ordinal* level (categorical)
-OR-
2. The *interval or ratio* data are *NOT normally distributed*
-OR-
3. The data has *outliers*
A 95% confidence interval for a mean indicates that
A. We can be 95% confident that the true population mean lies within the
interval.
B. 95% of the observations are located within the interval.
,C. We can be 95% confident that the true population mean lies within the
interval.
D. There is a 95% chance that the finding is statistically significant. correct answer
A. We can be 95% confident that the true population mean lies within the
interval.
A clinical nurse specialist on an inpatient unit compares two interventions for
reducing the number of medication errors. A statistical test comparing the
number of errors in each group yields a p-value of 0.50. This p-value indicates that
a. There is a statistically significant difference between the groups
b. There is a risk of a Type I error.
c. There is not a statistically significant difference between the groups.
d. There is not enough information presented to interpret the findings. correct
answer c. There is not a statistically significant difference between the groups.
A nurse practitioner student is completing his final practicum in the outpatient
clinic of the health care organization that is part of the university. As a part of the
course requirements for the final term, the student must complete a quality
improvement project. The student decides to examine whether the staff routinely
assess vaccination status for healthy adults. Since this is a quality improvement
project for the clinic and a course requirement for the student, does the student
need any additional approvals to review patient records for this project?
a. No, only research projects require approval.
b. Yes, the student needs to obtain appropriate permission to examine the data.
,c. No, this is a required student project and it is being conducted at the student's
own university medical center.
d. Yes, the student's project must undergo a full IRB review and approval. correct
answer b. Yes, the student needs to obtain appropriate permission to examine
the data
A nurse researcher compares two interventions for preventing catheter-
associated urinary tract infections (CAUTI) in an academic medical center. A
statistical test comparing the number of infections in the two groups yields a p-
value of 0.01. This p-value means that
a. There is a statistically significant difference between the groups.
b. There is not a statistically significant difference between the two groups.
c. A larger sample is needed to determine statistical significance.
d. The difference is clinically but not statistically significant. correct answer a.
There is a statistically significant difference between the groups.
A p-value of 0.50 from a Spearman Correlation Coefficient would indicate that
there is correct answer Not a statistically significant relationship between the
variables.
A Pearson correlation coefficient is 0.04. This correlation indicates that there is
correct answer A very weak relationship between the variables.
A r-value of 0.33 indicates correct answer A moderate relationship between the
variables.
, A researcher is comparing the outcome variable of cost in US dollars in 3
independent groups. The data are normally distributed without outliers. The
researcher should use which of the following tests to compare the 3 groups?
correct answer One-Way Anova
A researcher studies the relationship between hours of television watching and
BMI. The correlation coefficient is -0.35, which indicates correct answer a
moderate negative/inverse relationship
A researcher studies the relationship between the number of minutes of breast
pumping and the amount of milk produced per day in mothers of preterm infants.
The R-squared value is 0.49. This finding means that: correct answer The number
of minutes of pumping explains 49% of the variable in milk output.
A sample is
A. A subset of the population of interest.
B. Best selected by using nonprobability sampling methods.
C. Selected from the population of interest using a random process.
D. Best selected by using purposive sampling. correct answer A. A subset of the
population of interest.
A small sample size
a. Increases the risk of a type 2 error.
b. Increases the risk of a type 1 error.
c. Has no impact on the results of a statistical test.