Chapter·BiostatisticsNumber needed to treat/harm

Limitations and common misinterpretationsDownloads

10Questions
10Flashcards
1Tables & Flowcharts

Study Materials

Practice

Sample Questions

1

Group of 100 medical students took an end of the year exam. The mean score on the exam was 70%, with a standard deviation of 25%. The professor states that a student's score must be within the 95% confidence interval of the mean to pass the exam. Which of the following is the minimum score a student can have to pass the exam?

A45%

B63.75%

C67.5%

D20%

E65%

2

A scientist is studying the characteristics of a newly discovered infectious disease in order to determine its features. He calculates the number of patients that develop the disease over several months and finds that on average 75 new patients become infected per month. Furthermore, he knows that the disease lasts on average 2 years before patients are either cured or die from the disease. If the population being studied consists of 7500 individuals, which of the following is the prevalence of the disease?

A0.24

B0.02

C0.12

D0.005

E0.01

3

You conduct a medical research study to determine the screening efficacy of a novel serum marker for colon cancer. The study is divided into 2 subsets. In the first, there are 500 patients with colon cancer, of which 450 are found positive for the novel serum marker. In the second arm, there are 500 patients who do not have colon cancer, and only 10 are found positive for the novel serum marker. What is the overall sensitivity of this novel test?

A450 / (450 + 10)

B490 / (10 + 490)

C490 / (50 + 490)

D450 / (450 + 50)

E490 / (450 + 490)

+ 7 more in the PDF

More Number needed to treat/harm downloads

Browse all chapters

View all