A) Cataract B) Trachoma C) Refractive errors D) Vitamin A deficiency Answer (Select an option above to get the answer):
(Single Best Answer) Question 62: When an intervention is applied to community to evaluate its usefulness, it is termed as a trial for ?
A) Efficacy B) Effectiveness C) Efficiency D) Effect modification Answer (Select an option above to get the answer):
(Single Best Answer) Question 63: Several studies have shown that 85 % of cases of Lung Cancer are due to cigarette smoking. It is a measure of ?
A) Incidence rate B) Relative risk C) Attributable risk D) Absolute risk Answer (Select an option above to get the answer):
(Single Best Answer) Question 64: It is probable that physicians have a higher index of suspicion for tuberculosis in children without BCG scar than those with BCG scar. If this is so and an association is found between Tuberculosis and not having BCG scar, the association may be due to ?
A) Selection bias B) Interviewer bias C) Surveillance bias D) Non-response bias Answer (Select an option above to get the answer):
(Single Best Answer) Question 65: In a group of patients presenting to a hospital emergency with abdominal pain, 30% of patients have acute appendicitis, 70% of patients with appendicitis have a temperature greater than 37.5°C and 40% of patients without appendicitis have a temperature greater than 37.5°C. Considering these findings, which of the following statements is correct ?
A) The sensitivity of temperature greater than 37.5°C as a marker for appendicitis is 21/49 B) The specificity of temperature greater than 37.5°C as a marker for appendicitis is 42/70 C) The positive predictive value of temperature greater than 37.5°C as marker for appendicitis is 21/30 D) The specificity of the test will depend upon the prevalence of appendicitis in the population to which it is applied Answer (Select an option above to get the answer):
(Single Best Answer) Question 66: The number of malaria cases reported during the last 10 years in a town are given below: 250,320,190,300,5000,100,260,350,320& 160. The epidemiologist wants to find out the average number of malaria cases reported in that town during the last 10 years. The most appropriate measure of average for this data will be ?
A) Arithmetic mean B) Mode C) Median D) Geometric mean Answer (Select an option above to get the answer):
(Single Best Answer) Question 67: A Cardiologist wants to study the effect of an anti-hypertensive drug. He notes down the initial systolic blood pressure (mmHg) of 50 patients and then administers the drug on them. After a weekâ??s treatment, he measures the systolic blood pressure again. Which of the following is the most appropriate statistical test of significance to test the statistical significance of the change in blood pressure ?
A) Paired t - test B) Unpaired or independent t - test C) Analysis of Variance D) Chi-square test Answer (Select an option above to get the answer):
(Single Best Answer) Question 68: In assessing the association between maternal nutritional status and the birth weight of the newborns, two investigators A and B studied separately and found significant results with p values 0.02 and 0.04 respectively. From this information, what can you infer about the magnitudes of association found by the two investigators ?
A) The magnitude of association found by Investigator A is more than that found by B B) The magnitude of association found by Investigator B is more than that found by A C) The estimates of association obtained by A and B will be equal, since both are significant D) Nothing can be concluded as the information given is inadequate Answer (Select an option above to get the answer):