To assess a new diagnostic test, 300 patients aged 50 and above are evaluated using both the new test and the current gold-standard test for diagnosis.
The new test is observed to have a sensitivity of 80%, specificity of 60%, a positive predictive value of 66.7% and a negative predictive value of 75%.
What is the positive likelihood ratio of the test?
A case-control study is conducted to investigate the effectiveness of Ibuprofen in reducing confirmed arthritis pain compared to a placebo. A marker of 50% or more improvement in a patient’s symptoms measured on a numerical scale is considered significant. The following table displays the results of the study:
Total number of patients Achieved 50% improvement
Ibuprofen 180 90
Placebo 200 40
What is the relative risk of Ibuprofen achieving a 50% improvement in arthritis symptoms in this study?
A study is conducted to investigate the likelihood of stroke in high-risk patients taking a new oral antithrombotic medication versus warfarin. The study includes patients over the age of 60. The results are as follows:
Total number of patients Number who had a stroke within a 3 year period
New drug 200 10
Warfarin 600 12
What is the relative risk of experiencing a stroke within a 3 year period for patients over the age of 60 taking the new drug compared to warfarin?
Which one of the following statements best describes a type II statistical error?
Which statistical test is appropriate for analyzing normally distributed data that is measured?
Which of the following tests involves a comparison of within-group variance and between-group variance?
You sample 100 patients’ ages from your patient list and calculate the mean age to be 45 years old. This baseline data will be used before enrolling these patients on an exercise programme to measure the effect this has on age. The standard deviation of your data is 3. You wish to determine how accurate your estimate of the mean is likely to be.
What is the standard error of the mean?
A survey is conducted to determine the satisfaction level of customers with the new online ordering system, rating it out of 10. The scores obtained are: 9, 5, 3, 8, 7, 6, 4, 9. What is the median score?
What is the definition of the term that refers to the proportion of a disease that would be eliminated in a population if its disease rate were reduced to that of the unexposed group?
A study examines the likelihood of experiencing a heart attack (MI) in patients with established ischemic heart disease. Group A receives conventional treatment. After 7 years, 30 out of 150 patients have had an MI. Group B receives standard treatment plus a novel cardiac medication. After 7 years, 15 out of 90 patients have had an MI. What is the odds ratio of having an MI while taking the new drug compared to those who do not?