This document contains a 60 question midterm exam on epidemiology and biostatistics. The questions cover topics such as study designs, sampling methods, measures of central tendency, variables, responsibilities of clinicians and epidemiologists, and measures used in epidemiology like DALY, QALY, and HALE. The correct answers to each multiple choice question are also provided.

1. EPIDEMIOLOGY & BIOSTATISTICS – MIDTERM – OCTOBER – 2021
Student . ........................................................................................................
1. Purposive sampling is
a. the process of including whoever happens to be available at the time (called “accidental” or “haphazard”
sampling)
b. the process whereby the researcher selects a sample based on experience or knowledge of the group to
be sampled. Called “judgment” sampling
c. the process whereby a researcher gathers data from individuals possessing identified characteristics and
quotas
2. It is when you study an exceptional case represents the central phenomenon in dramatic terms. It
is...
a. Critical Sampling
b. Opportunistic Sampling
c. Snowball Sampling
3. Compute median from raw data 167, 131, 153, 188, 145, 195, 123, 199
a. 160
b. 140
c. 180
4. what type of variables is VOLTAGE?
a. Categorical
b. Numerical discrete
c. Numerical continuous
5. Cohort studies:
a. Describes the distribution of disease in relation to person, place and time
b. Describes, what is the likelihood of exposure in people with disease compared with people without
disease
c. Describes, what is the likelihood of developing disease for people who are exposed compared with
people who are not exposed
d. Describes, what is difference in outcome among people who received the intervention compared to
people who did not
6. Deals with patient, Conducts a physical exam - these responsibilities are assigned to...
a. Clinician
b. Epidemiologist
c. Both Сlinician and Epidemiologist
d. None of the listed
7. Analytic Studies
a. Generate hypotheses
b. Test hypotheses
c. Explains principles

2. 8. Convenience sampling is
a. the process of including whoever happens to be available at the time (called “accidental” or “haphazard”
sampling)
b. the process whereby the researcher selects a sample based on experience or knowledge of the group to
be sampled. Called “judgment” sampling
c. the process whereby a researcher gathers data from individuals possessing identified characteristics and
quotas
9. It is when you select certain sites or people because they possess similar characteristics. In this
strategy, you need to identify the characteristics and find individuals or sites that possess it. It is...
a. Maximal Variation Sampling
b. Typical Sampling
c. Homogenous Sampling
10. Compute median from raw data 25, 15, 37, 18, 19, 29, 31, 11, 45, 21
a. 17
b. 32
c. 23
11. What type of variables is WEIGHT?
a. Categorical
b. Numerical discrete
c. Numerical continuous
12. Case-control studies:
a. Describes the distribution of disease in relation to person, place and time
b. Describes, what is the likelihood of exposure in people with disease compared with people without
disease
c. Describes, what is the likelihood of developing disease for people who are exposed compared with
people who are not exposed
d. Describes, what is difference in outcome among people who received the intervention compared to
people who did not
13. Deals with population, Frames the question - these responsibilities are assigned to...
a. Clinician
b. Epidemiologist
c. Both Сlinician and Epidemiologist
d. None of the listed
14. Descriptive Studies
a. Generate hypotheses
b. Test hypotheses
c. Explains principles
15. Selecting every Kth subject from a list of the members of the population is named...
a. Random sampling
b. Stratified Random Sampling
c. Cluster sampling
d. Systematic sampling

3. 16. It is when you study a person or a site that is “typical” to those unfamiliar with the situation. You can
select a typical sample by collecting demographic data or survey data about all cases. It is...
a. Maximal Variation Sampling
b. Typical Sampling
c. Homogenous Sampling
17. Compute median from raw data 49, 51, 34, 62, 69, 36, 46, 55, 43
a. 55
b. 49
c. 69
18. What type of variables is NUMBER OF CHILDREN?
a. Categorical
b. Numerical discrete
c. Numerical continuous
19. Questions of Analytic Studies are:
a. What, who, where, and when
b. Why and how
c. How many
20. The process of randomly selecting intact groups, not individuals, within the defined population
sharing similar characteristics (Neighborhoods, School districts, Schools, Classrooms) is...
a. Random sampling
b. Stratified Random Sampling
c. Cluster sampling
d. Systematic sampling
21. It is when you select individuals that differ on a certain characteristic. In this strategy you should first
identify the characteristic and then find individuals or sites which display that characteristic. It is...
a. Maximal Variation Sampling
b. Typical Sampling
c. Homogenous Sampling
22. Compute mean from raw data 30, 27, 43, 35, 37, 50, 37, 45
a. 38
b. 48
c. 28
23. What type of variables is BITS PER MINUTE?
a. Categorical
b. Numerical discrete
c. Numerical continuous
24. Questions of Descriptive Studies are:
a. What, who, where, and when
b. Why and how
c. How many

4. 25. Sampling method, when population is divided into two ormore groups, according tosome criterion,
such as geographic location, grade level, age, or income, and subsamples are randomly selected from
each strata, is named...
a. Random sampling
b. Stratified Random Sampling
c. Cluster sampling
d. Systematic sampling
26. Compute standard deviation from raw data 332, 246, 488, 156, 222
a. 214
b. 114
c. 314
27. Compute mean from raw data 25, 27, 38, 30, 37, 43, 37, 43
a. 41
b. 23
c. 35
28. What type of variables is NUMBER OF PATIENTS?
a. Categorical
b. Numerical discrete
c. Numerical continuous
29. Draws conclusions, Gives recommendations - these responsibilities are assigned to...
a. Clinician
b. Epidemiologist
c. Both Сlinician and Epidemiologist
d. None of the listed
30. DALY (Disability Adjusted Life Years)
a. The equivalent number of years in full health that a newborn can expect to live based on current rates of
ill-health and mortality.
b. Measure of disease burden both the quality and quantity of life lived. It is used in assessing the value for
money of a medical intervention.
c. Av. No. of years an individual is expected to live free of disability.
d. Measure of overall disease burden, expressed as a no. of years lost due to ill - health, disability or early
death.
31. Selecting subjects so that all members of a population have an equal and independent chance of
being selected, is named...
a. Random sampling
b. Stratified Random Sampling
c. Cluster sampling
d. Systematic sampling
32. Compute standard deviation from raw data 60, 47, 15, 43, 30
a. 15
b. 24
c. 36

5. 33. Compute mean from raw data 24, 26, 37, 29, 36, 42, 36, 42
a. 43
b. 34
c. 29
34. What type of variables is RELIGIOUS AFFILIATION?
a. Categorical
b. Numerical discrete
c. Numerical continuous
35. The probability of disease developing in an individual in a specified time interval is:
a. Risk
b. Association
c. Causation
36. DFLE (Disability Free Life Expectancy)
a. The equivalent number of years in full health that a newborn can expect to live based on current rates of
ill-health and mortality.
b. Measure of disease burden both the quality and quantity of life lived. It is used in assessing the value for
money of a medical intervention.
. c. Av. No. of years an individual is expected to live free of disability
d. Measure of overall disease burden, expressed as a no. of years lost due to ill - health, disability or early
death.
37. In modern statistical studies, it is accepted that minimum size of sample should be...
a. 15% of the population
b. 30% of the population
c. 45% of the population
38. Compute standard deviation from raw data 600, 470, 170, 430, 300
a. 97
b. 147
c. 36
39. The value that occurs most frequently =
a. Mean
b. Median
c. Mode
40. What type of variables is POLITICAL PARTY?
a. Categorical
b. Numerical discrete
c. Numerical continuous
41. The relationship between an exposure of risk factor and an outcome is:
a. Risk
b. Association
c. Causation
42. QALY (Quality Adjusted Life Years) is

6. a. The equivalent number of years in full health that a newborn can expect to live based on current rates of
ill-health and mortality.
b. Measure of disease burden both the quality and quantity of life lived. It is used in assessing the value for
money of a medical intervention.
c. Av. No. of years an individual is expected to live free of disability.
d. Measure of overall disease burden, expressed as a no. of years lost due to ill - health, disability or early
death.
43. In modern statistical studies, it is accepted that...
a. Sample size larger than 15 and less than 100 are appropriate for most research
b. Sample size larger than 30 and less than 500 are appropriate for most research
c. Sample size larger than 100 and less than 1000 are appropriate for most research
44. Find mode from raw data 29, 13, 27, 17, 19, 11, 21, 27, 23, 25, 27, 15, 31, 23, 33, 35, 27
a. 11
b. 23
c. 27
45. The central value of an ordered distribution =
a. Mean
b. Median
c. Mode
46. What type of variables is MARITAL STATUS?
a. Categorical
b. Numerical discrete
c. Numerical continuous
47. Establishing that the association between an exposure and an outcome is casual is
a. Risk
b. Association
c. Causation
48. HALE (Health-Adjusted life expectancy) is
a. The equivalent number of years in full health that a newborn can expect to live based on current rates of
ill-health and mortality.
b. Measure of disease burden both the quality and quantity of life lived. It is used in assessing the value for
money of a medical intervention.
c. Av. No. of years an individual is expected to live free of disability.
d. Measure of overall disease burden, expressed as a no. of years lost due to ill - health, disability or early
death.
49. It is when you don't know the best people tostudy because of the unfamiliarity of the topic or the
complexity of events. So you ask participants during interviews to suggest other individuals to be
sampled. It is...
a. Critical Sampling
b. Opportunistic Sampling
c. Snowball Sampling
50. Find mode from raw data 29, 13, 17, 35, 19, 11, 21, 23, 25, 27, 15, 31, 23, 33, 35

7. a. 11 and 13
b. 33 and 31
c. 23 and 35
51. Sum of all entries / Number of entries =
a. Mean
b. Median
c. Mode
52. What type of variables is EYE COLOR?
a. Categorical
b. Numerical discrete
c. Numerical continuous
53. What is a cohort?
a. A well-defined group of individuals who share a common characteristic or experience
b. Group of Individuals born in the same year
c. Both a and b
54. Descriptive studies:
a. Describes the distribution of disease in relation to person, place and time
b. Describes, what is the likelihood of exposure in people with disease compared with people without
disease
c. Describes, what is the likelihood of developing disease for people who are exposed compared with
people who are not exposed
d. Describes, what is difference in outcome among people who received the intervention compared to
people who did not
55. Quota sampling is
a. the process of including whoever happens to be available at the time (called “accidental” or “haphazard”
sampling)
b. the process whereby the researcher selects a sample based on experience or knowledge of the group to
be sampled. Called “judgment” sampling
c. the process whereby a researcher gathers data from individuals possessing identified characteristics and
quotas
56. It is used after data collection begins, when you may find that you need to collect new information
to answer your research questions. It is...
a. Critical Sampling
b. Opportunistic Sampling
c. Snowball Sampling
57. Find mode from raw data 29, 13, 17, 19, 11, 21, 23, 25, 27, 15, 31, 23, 33, 35
a. 25
b. 24
c. 23
58. What type of variables is BODY TEMPERATURE?
a. Categorical
b. Numerical discrete

8. c. Numerical continuous
59. Intervention studies:
a. Describes the distribution of disease in relation to person, place and time
b. Describes, what is the likelihood of exposure in people with disease compared with people without
disease
c. Describes, what is the likelihood of developing disease for people who are exposed compared with
people who are not exposed
d. Describes, what is difference in outcome among people who received the intervention compared to
people who did not
60. Takes a history, Makes a diagnosis, Proposes a treatment - these responsibilities are assigned to...
a. Clinician
b. Epidemiologist
c. Both Сlinician and Epidemiologist
d. None of the listed
EPIDEMIOLOGY & BIOSTATISTICS – MIDTERM – OCTOBER – 2020
Student ....................................................................................................................