The presentation includes the simplified explanation of basic terms used in the field of biostatistics or preventive in social medicine.

1. Health and
population
statistics
Dr. Preet Mehta

2. 2
Contents
Introduction
Concept of health and well being
Spectrum of Health
Indicators of Health
Epidemiology

3. 1.
Introduction

4. What is Health???
The widely accepted definition of health is that given by the World
Health Organization (1948)
"Health is a state of complete physical, mental and social well-
being and not merely an absence of disease or infirmity"
In recent years, this statement has been amplified to include the
ability to lead a "socially and economically Productive life".

5. Psychologists have pointed out that the "well-being of an
individual or group of individuals have objective and subjective
components.
The objective components relate to such concerns as are
generally known by the term "standard of living" or "level of
living".
The subjective component of well being (as expressed by each
individual) is referred to as "quality of life"

6. Standard of Living
⇨ The usual scale of our
expenditure, the goods
we consume and the
services we enjoy.
⇨ The level of education,
employment status,
food, dress, house,
amusements and
comforts of modern
living .
Level of Living
⇨ The parallel term for standard of
living used in United Nations
documents is "level of living“.
⇨ consists of nine components:
health, food consumption, education.
occupation and working conditions,
housing, social security. clothing,
recreation and leisure, and human
rights.
⇨ Health is the most important
component of the level of living
because its impairment always
means impairment of the level of
living.
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7. Quality of life
It is the "subjective" component of well-being. "Quality of
life" was defined by WHO as: "the condition of life
resulting from the combination of the effects of the
complete range of factors such as those determining
health, happiness (including comfort in the physical
environment and a satisfying occupation), education,
social and intellectual attainments, freedom of action,
justice and freedom of expression".

8. Physical quality life index (PQLI)
• Three indicators, viz. infant mortality, life expectancy at age one,
and literacy.
• These three components measure the results rather than inputs.
As such they lend themselves to international and national
comparison.
• For each component, the performance of individual countries is
placed on a scale of 0 to 100.
• The composite index is calculated by averaging the three
indicators, giving equal weight to each of them. The resulting
PQLI thus also is scaled 0 to 100.

9. • It may be mentioned that PQLI has not taken per capita
GNP into consideration, showing thereby that "money is not
everything".
• For example, the oil-rich countries of Middle East with high
per capita incomes have in fact not very high PQLIS. At the
other extreme, Sri Lanka and Kerala state in India have low
per capita incomes with high PQLIS.
• In short, PQLI does not measure economic growth; it
measures the results of social, economic and political
policies. It is intended to complement, not replace GNP.
The ultimate objective is to attain a PQLI of 100.

10. Human Development Index (HDI)
• It is defined as "a composite index focusing on three basic
dimensions of human development to lead a long and healthy life
measured by life expectancy at birth; the ability to acquire
knowledge, measured by mean years of schooling and expected
years of schooling; and the ability to achieve a decent standard of
living, measured by gross national income per capita in PPP US $.
• Thus the concept of HDI reflects achievements in the most basic
human capabilities, viz, leading a long life, being knowledgeable
and enjoying a decent standard of living

11. • Thus by focusing on areas beyond income and
treating income as a proxy for a decent standard of
living, the HDI provides a more comprehensive
picture of human life than income does.
• The HDI values range between 0 to 1. The HDI value
for a country shows the distance that it has already
travelled towards maximum possible value to 1, and
also allows comparisons with other countries.(India
rank 131 out of 189 with the value of 0.645)

12. 2. Spectrum of health

13. Spectrum of health
• Health and disease lie along a continuum, and there is no
single cut-off point.
• The lowest point on the health-disease spectrum is death and
the highest point corresponds to the WHO definition of
positive health.
• It is thus obvious that health fluctuates within a range of
optimum well-being to various levels of dysfunction.
• The spectral concept of health emphasizes that the health of
an individual is not static; it is a dynamic phenomenon and a
process of continuous change.
• What is considered maximum health today may be minimum
tomorrow.
• There are degrees or "levels of health" as there are degrees or
severity of illness. As long as we are alive there is some
degree of health in us.

14. Indicators of Health
• Indicators are only an indication of a given situation or reflection of
that situation.
• In WHO’s guidelines for health programme evaluation they are
defined as variables which help to measure changes.
• There has been some confusion over terminology: health indicator as
compared to health index.
• It has been suggested that in relation to health trends, the term
indicator is to be preferred to index, whereas health index is generally
considered to be an amalgamation of health indicators.

15. Characteristics of indicators
a. should be valid, i.e., they should actually measure what they are
supposed to measure;
b. should be reliable and objective. i.e., the answers should be the
same if measured by different people in similar circumstances;
c. should be sensitive, i.e., they should be sensitive to changes in
the situation concerned,
d. should be specific, i.e., they should reflect changes only in the
situation concerned,
e. should be feasible, i.e., they should have the ability to obtain
data needed;
f. should be relevant, i.e., they should contribute to the
understanding of the phenomenon of interest.

16. 1. Mortality indicators
2. Morbidity indicators
3. Disability rates
4. Nutritional status
indicators
5. Health care delivery
indicators
6. Utilization rates
7. Indicators of social and
mental health
8. Environmental indicators
9. Socio-economic indicators
10. Health policy indicators
11. Indicators of quality of life,
12. Other indicators.

17. Mortality Indicators
1. Infant mortality rate(28.771)
2. Child death rate
3. Expectation of life (70.42)
4. Under-5 proportionate
mortality rate (35.73)
5. Age specific mortality rate
6. Adult mortality rate
7. Maternal (puerperal )
mortality rate
8. Disease specific mortality
rate
9. Proportional mortality rate
10. Case fatality rate
11. Years of potential life
lost(YPLL)
12. Crude death rate

18. Morbidity Indicators
• Incidence or prevalence
• Notification rates
• Attendance rates at OPD etc.
• Admission, re-admission and discharge rates
• Duration of stay in hospital
• Spells of sickness or absence from work or school

19. Disability rates
Event type indicators
numbers of days restricted activity
Bed disability days
Work loss days
Person type indicators
Limitation of mobility
Limitation of activity

20. Quality adjusted life years (QALY)
• Measure of disease burden – both quality and quantity
• 1 QALY= 1 year of life x 1 utility value
Disability adjusted life years (DALY)
• Measure of overall disease burden, expressed as a number of years
lost due to ill-health, disability or early death.
• Originally developed by Harvard university for world bank in 1990 and
WHO adopted in 2000.
• DALY=YLL+YLD ( years of lost life no. of death at each age x expected
remaining years & Years lost to disability no. of incident cases due to
injury or illness x average duration of the disease and a weighting
factor reflecting the severity

21. ⇨ Nutritional
status
Indicators
Anthropometric of
pre-school children
,height, prevalence
of Low birth weight
⇨ Health care
delivery
indicators
1. Doctor –
population ratio
2. Doc- nurse
3. Population-bed
4. Pop. per
health/subcentr
e
5. Pop. Per trained
birth attendent
⇨ Utilization rates
1. Proportion of
fully immunized
2. Percentage of
pregnant
women who
received ante
natal care
3. Bed occupancy
rate ..etc

22. ⇨ Indicators of
social and
mental health
Suicide, homicide,
other crimes,RTA,
alcohol or drug
abuse etc
⇨ Environmental
indicators
Pollution of air,
water, radiation,
solid waste, noise
etc.
⇨ Socio-
economic
indicators
Rate of population
increase, per capita
GNP, level of
unemployment,
family size, literacy
rates etc
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23. ⇨ Health policy
indicators
⇨ Indicators of
quality of life
⇨ Social
indicators
⇨ Basic needs
indicators
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