Biostatistics

1. Laparoscopy was used to diagnose cyst. Its sensitivity was 90 % and specificity was 90 %, what will be false positive rate?

2. Laparoscopy was used to diagnose cyst. Its sensitivity was 10 % and specificity was 90 %, what will be false negative rate?

3. New drug was introduced in a trial. The incidence of adverse outcome reported was 65%. Whereas in those who received placebo drug the incidence of adverse outcome reported was 80%. What is the absolute risk reduction?

4. When does the Odds ratio approximate risk ratio:

5. A tumor marker is revolutionized for detection of endometrial cancer, 60 women included in study, however confirmatory test shows only 40 have ca endometrium, 8 of them tested negative with new marker. What is the sensitivity of test?

6. Histogram is used to summarise which of the variable

7. Which of the following is true about Type 1 error?

8. What is true about Standard error of mean (SEM)?

9. Statistical heterogeneity indicates

10. Gestational age in weeks is which type of variable?

11. 32 women got conceived following ovulation suppression and 10 did not. 40 women got conceived following placebo and 10 did not. The common odds ratio for pregnancy following ovulation suppression versus placebo or no treatment was how much?

12. What do the bottom and top represent on the box-and-whisker plot?

13. Out of 100 women screened for ectopic using a new test 30 tested positive for ectopic. However only 27 women actually were ectopic according to gold standard USG plus Beta HCG test. What is the sensitivity of the new test?

14. Out of 100 babies with APGAR score more than 7, 30 of them had outcome of neonatal mortality and morbidity. Out of 100 babies with APGAR score less than 7, 60 of them had outcome of neonatal mortality and morbidity. What are the odds of neonatal mortality in APGAR score < than 7 compared to > than 7?

15. The null hypothesis states that a given variable is without effect. What type of error is present when the null hypothesis is incorrectly not rejected?

16. What is the best description of power?

17. Which statistical value provides details of how close a sample mean is to the population mean?

18. Probability is the measure of a given observation occurring by chance and is denoted by symbol P. what value of P indicates that an observation will definitely occur?

19. 100 women with heavy post menopausal bleeding were taken papillary endometrial biopsy prior to hysterectomy, to test the ability of the biopsy to detect endometrial cancer.

What is the specificity of the endometrial biopsy?

20. A new antenatal screening test to assess the level of cervical effacement in threatened pre term delivery has been developed. In trials this test has a high degree of specificity. What is the definition of the term specificity?

21. Junior doctor has carried out research product in the early pregnancy unit low serum progesterone at 6 weeks of gestation has been evaluated for its ability to predict first trimester miscarriage 200 women were recruited the results are as follows

What is the positive predictive value of low serum progesterone in predicting miscarriage?

22. The following is the gestation age of women in weeks with Pregnancy induced hypertension recruited for a drug trial. 20, 22, 21, 23, 19, 24, 25, 26, 28, 30 and 22 weeks. What is the median gestational age?

23. Standard error of mean is calculated by

24. Mean systolic blood pressure (SBP) of 36 women with PIH was 162 mm Hg. SD of SBP was 18 mm Hg. What is the SEM (Standard error of mean)?

25. What represent the 2 axis of ROC curve?

26. Calculate the odds of asymmetrical IUGR and symmetrical IUGR for Apgar < 7

27. You are carrying out analysis of a new test for DVTs and decide to plot a receiver operating characteristic curve. What are the axis of the curve?

28. A publication reports the outcome of a new therapy in a placebo controlled primary prevention of venous thromboembolism (VTE). 200 patients were randomized to receive the new therapy and 200 allocated to placebo. The study was completed over a 2 year period. In the placebo group there were 20 having venous thromboembolism and in the group treated with the new therapy there were 10 having venous thromboembolism. What is the number needed to treat to prevent one VTE over the course of this study?

29. What type of variable is ABO Blood Group?

30. For preterm birth (PTB) prediction risk within 7 days of testing in pregnant women with cervical length between 15-30 mm , PAMG-1 test (placental alpha microglobulin-1) in cervicovaginal secretions collected immediately following transvaginal ultrasound (TVUS) of women with signs and symptoms of preterm labour was done. This study included 200 women. 175 of the women who tested positive with PAMG test delivered PTB. 25 of the women who tested negative delivered PTB. What is the sensitivity of PAMG test?

31. With regards to a screening test in relation to the diagnostic test of a disease, the results have yielded the following 2×2 contingency table:

What is the specificity of the test?

32. Body mass index (BMI) is known to be normally distributed across the population with a mean of 25 and standard deviation of 5. How many out of 100 patients in a population will be obese?

33. In a study of 100 women presenting with symptoms of preterm labour, a cervicovaginal fetal fibronectin (fFN) test was assessed in predicting spontaneous preterm birth (PTB). The following results were obtained:

What is the Negative predictive value (NPV) of this test?

34. An investigator compares a chart of hemoglobin (HbA1c) levels in two groups of gestational diabetes patients: those who take standard and new drug. Assume the (HbA1c) levels of both groups were found to be positively skewed distribution. A logarithmic transformation was taken to be symmetrise. Which of the following tests is most likely to be employed by the investigator to analyze the study results?

35. The following table shows the following results:

What is the positive predictive value of the new test?

36. In a given sample for a group of size 16, the standard deviation of the data is 12 and the mean is 2. What is the standard error of mean (SEM)?

37. A publication reports the outcome of a new therapy in a placebo controlled primary prevention of venous thromboembolism (VTE). 200 patients were randomised to receive the new therapy and 200 allocated to placebo. The study was completed over a 2 year period. In the placebo group there were 100 have venous thromboembolism and in the group treated with the new therapy there were 50 have venous thromboembolism. What is the number needed to treat to prevent one VTE over the course of this study?

38. In an investigation to study the effect of smoking in cancer cervix, it is observed that 30 of the 60 patients were smokers as compared to 20 out of 60 control subjects. The odds ratio of cancer cervix associated with smoking will be?

39. The number of hours worked per week for a sample of ten students is shown below.

40. One researcher wishes to assess the postoperative recovery for a group of postmenopausal women who had a hysterectomy. He classified the patients as fell “worse,” “same,” or “improve”. Which level of measurement is this classification?

41. Mann whitney U test is

42. What level of measurement uses a verbal scale to measure data; slight, moderate and severe?

43. Mean hemoglobin of a sample of 100 pregnant women was found to be 10 mg% with a variance of 1.0 mg%. The standard error of the estimate would be:

44. Which statistical test requires a normal population distribution?

45. What is the correct formula to calculate the positive predictive value? If TP = true positive; FP = false positive; TN = true negative; FN = false negative

46. A revolutionary tumour marker has been trialed for detecting endometrial carcinoma. 140 women were included in the trial; the result shows that 90 women had a positive tumour marker however only 30 had endometrial cancer. 5 women who had endometrial cancer were negative for the tumour marker. The sensitivity of the new tumour marker is

47. Forest plot: horizontal lines represent

48. What is represented by the equation Sensitivity/(1-specificity)?

49. Sample size 30, variance 25 and standard error of mean 3. What is the data set’s Standard deviation?

50. The following is a plot

This type of plot is used for which type of analysis?

51. Which Study design describe comparison between Shoulder dystocia and neonatal birth weight?

52. How could you calculate the negative predictive value of the new test?

53. Q about 2Tmode2T (Graph) where 3, 15, 28, 29, 15, 100 Pregnant students, and
study time 1hr, 2, 3, 4, 5, 6 hrs. What is value of 2Tmode?

54. Forest plot: horizontal lines represent

55. What is represented by the equation Sensitivity/(1-specificity)?

56. Sample size 30, variance 25 and standard error of mean 3. What is the data set’s Standard deviation?

57. Some-town in the UK, has a population of 350,000. During 2010, there were 20,000 live births, 70 stillbirths, and 50 early neonatal deaths. Among the births that year, there were 20 sets of twins and four sets of triplets, and four mothers died at the time of delivery. Which of the following represents the perinatal mortality rate in this town during 2009?

58. The following scatter plot is used to view what type of data?

59. What is the correct formula to calculate the specificity?
TP = true positive; FP = false positive; TN = true negative; FN = false negative

60. The Eighth Confidential Enquiry into maternal deaths in the United Kingdom defines maternal mortality as: