AKT-1978
A 42-year-old man is currently waiting for the results of his recent HIV test. The test has a specificity of 99.6%. What can be said about this test?
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AKT-1979
A new screening tool for lower gastrointestinal malignancies, known as the Faecal Immunochemical Test (FIT), has been developed. The researchers want to determine the effectiveness of the test in detecting colorectal cancer in individuals aged 50 and above.
To assess the test’s accuracy, the researchers conducted a study where all participants aged 50 and above underwent a FIT and were subsequently followed up with a colonoscopy, which is considered the gold standard test for detecting colorectal cancer.
Out of the 100 participants who tested positive on the initial FIT, 80 were confirmed to have colorectal cancer on colonoscopy. On the other hand, out of the 900 participants who tested negative on the initial FIT, 20 were later found to have colorectal cancer on colonoscopy.
What is the sensitivity of the FIT in detecting colorectal cancer in individuals aged 50 and above?
AKT-1980
A study is conducted to evaluate the efficacy of a new auto-antibody test as a screening tool for prostate cancer. The study involves 1000 patients, out of which 70 test positive for the auto-antibody. Among the positive cases, 50 are confirmed to have prostate cancer through biopsy. On the other hand, 10 patients who tested negative for the auto-antibody were later diagnosed with prostate cancer.
What is the percentage of positive predictive value of this test?
AKT-1981
A new screening tool for lower gastrointestinal malignancies has been developed known as the Faecal Immunochemical Test (FIT). The test is hoped to be an improvement on the previous stool tests as the FIT targets human haemoglobin.
The researchers would like to determine the specificity of the FIT test for colorectal cancer in a study involving 3000 participants aged 50 and above. All participants undergo a FIT and are subsequently evaluated with colonoscopy, which is considered the gold standard test.
Out of the 1200 participants who tested positive on the FIT, 800 were later confirmed to have colorectal cancer on colonoscopy.
On the other hand, out of the 1800 participants who tested negative on the FIT, 100 were later found to have colorectal cancer on colonoscopy.
What is the specificity of the FIT test for colorectal cancer in this study?
AKT-1982
As part of a clinical audit, a medical student is analysing the characteristics of patients attending a hypertension clinic. She calculates that the mean age of the patients is 56 years old, and that the variance of the data is 64. She wants to calculate the standard deviation of the data set.
What is the connection between standard deviation and variance?
AKT-1983
The standardised mortality ratio for a group of elderly patients with antisocial personality disorder is 120 (95% CI 90-130). How should this result be interpreted?
AKT-1984
A researcher is tasked with evaluating the effectiveness of olanzapine versus haloperidol in reducing symptom severity of schizophrenia (as per the Positive and Negative Syndrome Scale) for each dollar spent. What would be the most suitable study approach?
AKT-1985
You have collected blood pressure data of patients given a new medication being tested as a treatment for hypertension. The data includes the patient’s initial blood pressure reading, followed by a second measurement taken 10 minutes after administering the medication.
Upon initial analysis, it was found that the differences between the two measurements do not conform to a normal distribution.
What statistical test would be the most suitable to determine if there is a significant difference between the blood pressure readings before and after the administration of the new medication?
AKT-1986
A disease is discovered to have a standard mortality ratio of 140 in a surveyed population. Is it accurate to say that the disease is more fatal in this age group?
AKT-1987
A study testing a new prostate cancer screening tool enrolls 52,820 participants. Among the 8950 participants diagnosed with prostate cancer through histological examination, 8900 had a positive test outcome. Meanwhile, 13,750 healthy participants had a positive screening result. What is the specificity of this novel screening tool?