MRCGP AKT Category: Evidence Based Practice, Research And Sharing Knowledge

AKT-1936

A researcher is conducting a study into the concentration (in units/ml) of the hormone cortisol in the saliva of young adults with and without a history of anxiety disorders. Cortisol levels are measured in 20 individuals with a history of anxiety disorders (the anxiety group) and in 30 age-matched individuals without a history of anxiety disorders (the control group). The researcher finds that the data from both groups follow a normal distribution.

The researcher wants to investigate whether there is a statistically significant difference in cortisol concentration between the saliva of the anxiety group and the control group.

What would be the most appropriate statistical test?

AKT-1937

A study compares the effectiveness of two treatments for hypertension. The first treatment has a success rate of 75% whilst the second treatment has a success rate of 82%. What type of significance test should be used for comparing the two results?

AKT-1938

A researcher is conducting a study that compares a new exercise program for improving cognitive function in adults over 60 with existing methods. Her null hypothesis is that there is no difference between the efficacy of the new exercise program and existing cognitive function improvement methods. After collecting sufficient data, she wants to calculate the probability of finding a statistically significant difference between the efficacy of the new exercise program and the existing methods.

Which value is this referring to?

AKT-1939

Which one of the following would invalidate the use of the Student’s t-test when performing a significance test?

AKT-1940

The Delphi method is utilized to assess what?

AKT-1909

A rapid urine screening test is developed to detect Chlamydia in individuals over the age of 50. A trial involving 200 men and women in this age group is performed comparing the new test to the existing NAAT techniques:

Chlamydia present Chlamydia absent
New test positive 20 3
New test negative 5 172

What is the negative predictive value of the new test?

AKT-1925

A new oral-hypoglycaemic is being developed. A number of different study types are considered to demonstrate efficacy in reducing the HbA1c. Which one of the following study designs would require the most participants to produce a significant result?

AKT-1910

A systematic review on the use of apixaban for left ventricular thrombus in elderly patients has revealed a noteworthy decrease in hospitalisation and mortality rates. The meta-analysis comprised twenty randomised and non-randomised studies. The researchers were apprehensive about the possibility of studies with positive outcomes being published more frequently than those with negative results and opted to explore the presence of publication bias.

What is the most suitable approach to evaluate publication bias in this analysis?

AKT-1911

A new drug is tested for the treatment of heart disease. Drug B is administered to 800 people with early stage heart disease and a placebo is given to 700 people with the same condition. After 3 years, 500 people who received drug B had survived while only 350 who received the placebo survived. What is the number needed to treat to save one life?

AKT-1912

A study examines the effectiveness of bisphosphonates in managing pain caused by bone metastases in a group of 120 patients. Among them, 40 patients were treated with conventional therapy involving NSAIDs and radiotherapy, while the remaining 80 patients received bisphosphonates. Out of these 80 patients, 40 experienced considerable pain relief. What are the odds of a patient with bone metastases receiving significant pain relief from bisphosphonates?