Epidemiology

Question 1

Triad of epidemiological questions?

Answer 1

How does pattern of disease vary over time?
How does place in which population lives affect disease pattern?
How do personal characteristics of people in a population affect disease pattern?

Question 2

What does descriptive epidemiology do?

Answer 2

Describe pattern of disease

Question 3

What does analytical epidemiology do?

Answer 3

Make associations of observed patterns to make inferences in hypothesis driven manner

Question 4

What is genetic epidemiology?

Answer 4

Epidemiological evaluation of role of inherited causes of disease in families and populations

Question 5

What did Morton define genetic epidemiology as?

Answer 5

Science which deals with etiology, distribution and control of disease in groups of relatives and with inherited causes of disease in populations

Question 6

Define incidence

Answer 6

Number of new cases diagnosed in specified time interval for specified size of population at risk

Question 7

What determines population size for incidence?

Answer 7

Mid-interval population

Question 8

Give formula for incidence

Answer 8

Number of newly diagnosed cases/mid-2014 population at an area

Question 9

What must new cases include for incidence calculation?

Answer 9

Newly diagnosed patients whether cured or dead

Question 10

What is the advantage of cumulative incidence?

Answer 10

Valid in cohort studies where attrition is low

Question 11

When is cumulative incidence not helpful?

Answer 11

High attrition rate - as dropouts are excluded from being counted as new cases

Question 12

What is used if high attrition rate and need to calculate incidence?

Answer 12

Incidence rate

Question 13

What is incidence rate?

Answer 13

Number of new cases per person-year of observation

Question 14

What is the unit of incidence rate?

Answer 14

Time-1

Question 15

When are incident rate ratios used?

Answer 15

When reporting results that compare two groups incidence rates

Question 16

What is prevalence?

Answer 16

Number of existing cases in specified population for period of observation

Question 17

What is point prevalence?

Answer 17

Prevalence in cross-sectional observation

Question 18

What is period prevalence?

Answer 18

Prevalence in longitudinal observation

Question 19

Which cases are counted in prevalence?

Answer 19

New cases

Diagnosed before observation but still suffering disease

Question 20

What does prevalence not count re cases?

Answer 20

Previously diagnosed but now cured or dead

Question 21

Calculation of point prevalence

Answer 21

Number of existing cases/cross sectional population at an area on 11/11/2018

Question 22

Calculation of period prevalence

Answer 22

Number of existing cases/mid year population at an area

Question 23

Which illnesses will have higher prevalence?

Answer 23

Chronic

Question 24

What formula expresses relationship between incidence and prevalence?

Answer 24

Prevalence = incidence x duration of illness

Question 25

What is lifetime prevalence?

Answer 25

Proportion of individuals in the population who have ever manifested a disease who are alive on a given day.

Question 26

What is lifetime morbid risk?

Answer 26

Probability of a person developing the disorder during the entire period of their life (often a specified period)

Question 27

What does lifetime morbid risk include?

Answer 27

Entire lifetime of a birth cohort both past and future | Includes those deceased at time of survey

Question 28

What is used to calculate lifetime morbid risk for low incidence disorders?

Answer 28

Summation of age-specific incidence rates live approximate LMR

Question 29

What is baseline prevalence?

Answer 29

Usual prevalence of a disease in a community

Question 30

When is a disease said to be endemic?

Answer 30

If baseline is low to moderate and continues without significant fluctuation

Question 31

What is hyperendemic occurrence?

Answer 31

A persistent but high baseline

Question 32

What occurrence are most psychiatric disorders classed as?

Answer 32

Low-level endemic

Question 33

What is sporadic occurrence?

Answer 33

Irregular pattern of significant fluctuations from baseline

Question 34

What is epidemic?

Answer 34

Occurrence within an area clearly exceeds expected level in a given time period

Question 35

What is a pandemic?

Answer 35

An epidemic in wide geographical proportion

Question 36

What is a crude rate?

Answer 36

Any rate applicable to a while population

Question 37

What is a specific rate?

Answer 37

Any rate applicable to a subgroup of a population

Question 38

What is a standardised rate?

Answer 38

A rate applicable to a hypothetical population with an adjusted variable e.g. age

Question 39

What is crude mortality rate?

Answer 39

Ratio between number of deaths du to all-cause in a population and total population sie

Question 40

What is case fatality rate?

Answer 40

Ratio between number of deaths from specific disease and number of people affected by the disease in population.

Question 41

What is case fatality rate a measure of?

Answer 41

Fatal severity of disease studied

Question 42

What is proportionate mortality rate?

Answer 42

Ratio between deaths due to specific cause and total number of deaths in a population

Question 43

What is proportionate mortality rate a measure of?

Answer 43

Contribution of a disease to societal mortality burden

Question 44

What is years of potential life lost?

Answer 44

Sum of the differences between some predetermined end point and ages of death for those who died before that end point

Question 45

What is years of potential life lost a measure of?

Answer 45

Impact of premature mortality on a population

Question 46

Most commonly used end points in years of potential life lost?

Answer 46

65 years | Average life expectancy

Question 47

What do years of potential life lost give more weight to?

Answer 47

Earlier deaths

Question 48

What is disability-adjusted life years (DALY)?

Answer 48

Health gap measure that extends the concept of potential years of life lost due to premature death to include equivalent years of healthy life lost in states of disability

Question 49

What does one DALY represent?

Answer 49

Loss of one year of equivalent full health

Question 50

What can be used to calculate DALYs?

Answer 50

3% time discounting and non-uniform age weights that give less weight to years lived at young and older ages

Question 51

Calculation for DALY

Answer 51

Years of life lost due to premature mortality in population (YLL) + years lost due to disability for cases (YLD)

Question 52

Calculation for YLL?

Answer 52

Number of deaths x Standard life expectancy at age of death in years (LE)

Question 53

Calculation for YLD

Answer 53

Number of incident cases x weight given to disability x average duration of case until remission or death (life until death in years)

Question 54

Define neonatal death

Answer 54

Liveborn that dies within 28 days

Question 55

Define early neonatal death

Answer 55

Liveborn that dies within 7 days

Question 56

Define late neonatal death

Answer 56

Liveborn that dies between 7-28 days

Question 57

Define stillbirth

Answer 57

Fetus that dies before birth but after 24 weeks

Question 58

Define perinatal deaths

Answer 58

Still births + early neonatal births

Question 59

Define postneonatal deaths

Answer 59

Deaths from 1 month to 1 year

Question 60

Define infant deaths

Answer 60

Deaths under 1 year

Question 61

What does a frequency polygon show?

Answer 61

Frequency distribution

Question 62

How does one create frequency polygon?

Answer 62

Mark number of observations within an interval with single point placed at midpoint of interval and then connect these points

Question 63

What can population pyramids be helpful for?

Answer 63

Insight into trends in population over time

Question 64

Types of population pyramids

Answer 64

Constrictive Expansive Stationary

Question 65

What is a constrictive pyramid?

Answer 65

Fewer people in younger age categories.

Question 66

Which type of countries have a constrictive pyramid?

Answer 66

E.g. USA - baby boom populations shift to more conservative birth dats

Question 67

What is an expansive pyramid?

Answer 67

Greater number of people in younger age categories High birth rates Low life expectancy

Question 68

Which type of pyramid is seen in developing countries?

Answer 68

Expansive

Question 69

What is an expansive pyramid?

Answer 69

Equal numbers of people in all categories, tapering towards old age categories Low, constant birth rate High QoL

Question 70

How many psychiatric-epidemiological studies belong to first generation?

Answer 70

16

Question 71

What defines first psychiatric-epidemiological generation?

Answer 71

Studies carried out before World War II

Question 72

What did first generation psychiatric-epidemiological studies focus on?

Answer 72

Health care agency registered prevalence of mental disorders in relation to community characteristics

Question 73

How many studies in the second generation of psychiatric-epidemiological studies?

Answer 73

60

Question 74

What did second generation psychiatric-epidemiological studies focus on?

Answer 74

Diagnostic criteria Classification Nomenclature of psychiatric disorder

Question 75

What type of studies were the second generation psychiatric-epidemiological studies?

Answer 75

Field surveys in unstructured clinical interviews

Question 76

When did the third generation of psychiatric-epidemiological studies start?

Answer 76

1970

Question 77

What was the major objective of third generation psychiatric-epidemiological studies?

Answer 77

Increase reliability of psychiatric diagnoses | Obtain precise estimates of prevalence and incidence of MH disorders

Question 78

What does fourth generation of psychiatric-epidemiological studies include?

Answer 78

Comprehensive sets of biological markers such as brain imaging, CSF, bloods etc Large scale cross-sectional surveys e.g. H70 study