The document discusses health information systems, outlining various sources of health data including census, vital event registration, and disease notifications. It emphasizes the importance of accurate data for assessing health status, managing health services, and supporting research. Additionally, it covers different statistical measures such as mortality and morbidity rates, emphasizing their role in understanding public health trends.

1. Dr. Shubhangi Kshirsagar
Assistant professor
Swasthavritta & Yoga department

2. Health information
A health information system is defined as -"a
mechanism for the collection, processing,
analysis and transmission of information
required for organizing and operating health
services, and also for research and training"
Dr. Shubhangi Kshirsagar 2

3. Sources of health information
1. Census
2. Registration of vital events
Ex. Birth, death, marriage,
divorce etc.
3. Sample registration system
4. Notification of disease
5. Hospital records
6. Disease registers
7. Record linkage
8. Epidemiological surveillance
9. Other health service records
10. Environmental health data
11. Health manpower statistics
12. Population surveys
13. Other routine statistics
related to health
14. Non quantifiable
information
Dr. Shubhangi Kshirsagar 3

4. Sources of health information
1. Census
 It is taken at regular intervals, usually of 10
years.
 Definition - “The total process of collecting,
compiling and publishing demographic,
economic and social data pertaining at a
specified time or times, to all persons in a
country or delimited territory“.
 Drawback of census - as a data source i.e. the
full results are usually not available quickly.
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5. 2. Registration of vital events
 Whereas census is an intermittent counting of
population, registration of vital events (e.g.,
births, deaths) keeps a continuous check on
demographic changes.
 If registration of vital events is complete and
accurate, it can serve as a reliable source of
health information.
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6. The Central Births and Deaths
Registration Act, 1969
Aim - To improve the civil registration system.
 The Act provides for compulsory registration of
births and deaths throughout the country and
compilation of vital statistics in the States.
 The Act also fixes the responsibility for
reporting births and deaths.
 While the public (e.g., parents, relatives) are to
report events occurring in their households, the
heads of hospitals, nursing homes, hotels, jails
or dharmashalas are to report events occurring in
such institutions to the concerning Registrar.
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7. 3. Sample Registration System( SRS)
 The SRS is a dual-record system, consisting of
continuous enumeration of births and deaths
by an enumerator and an independent survey
every 6 months by an investigator-supervisor.
 The half-yearly survey, in addition to serving
as an independent check on the events
recorded by the enumerator, produces the
denominator required for computing rates.
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8. 4. Notification of diseases
 Historically notification of infectious diseases was
the first health, information sub-system to be
established.
 The primary purpose of notification is to effect
prevention and/or control of the disease.
 Notification is also a valuable source
of morbidity data i.e., the incidence and
distribution of certain specified diseases which
are notifiable.
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9.  Lists of notifiable diseases vary from country to
country, and also within the same country
between the States and between urban and rural
areas.
 Usually diseases which are considered to be
serious menaces to public health are included in
the list of notifiable diseases.
 At the international level, the following diseases
are notifiable to WHO in Geneva under the
International Health Regulations (IHR), viz.
cholera, plague and yellow fever.
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10.  A few others louse-borne typhus, relapsing
fever, polio, influenza, malaria, rabies and
salmonellosis are subject to international
surveillance.
 The concept of notification has been
extended to many non-communicable
diseases and conditions notably cancer,
congenital malformations, mental illness,
stroke and handicapped persons
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11. 5. Hospital records
 Hospital data constitute a basic and primary
source of information about diseases
prevalent in the community.
 The eighth report of the WHO Expert
Committee on Statistics recommended that
hospital statistics be regarded in all countries
as an integral and basic part of the national
statistical programme.
Dr. Shubhangi Kshirsagar 11

12. 6. Population surveys
 Surveys for evaluating the health status of a
population
 Surveys for investigation of factors affecting
health and disease, e.g., environment,
occupation.
 Surveys relating to administration of health
services, e.g., use of health services.
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13. Survey methods
a. Health interview (face-to-face) survey
b. Health examination survey
c. Health records survey
d. Mailed questionnaire survey
Dr. Shubhangi Kshirsagar 13

14. 7. Epidemiological surveillance
 In many countries, where particular diseases are
endemic, special control/eradication programmes
have been instituted, as for example national
disease control programmes against malaria,
tuberculosis, leprosy, filariasis etc.
 As part of these programmes, surveillance systems
are often set up (e.g., malaria) to report on the
occurrence of new cases and on efforts to control the
diseases (e.g., immunizations performed).
 These programmes have yielded considerable
morbidity and mortality data for the specific
diseases.
Dr. Shubhangi Kshirsagar 14

15. Uses of health information
1. To measure the health status of the people
and to quantify their health problems and
medical and health care needs.
2. For local, national and international
comparisons of health status. For such
comparisons the data need to be subjected to
rigorous standardization and quality control.
3. For planning, administration and effective
management of health services and
programmes.
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16. 4. For assessing whether health services are
accomplishing their objectives in terms of
their effectiveness and efficiency.
5. For assessing the attitudes and degree of
satisfaction of the beneficiaries with the
health system.
6. For research into particular problems of health
and disease.
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17. Vital statistics

18. Vital statistics
Vital statistics is accumulated data
gathered on live births, deaths, migration,
fetal deaths, marriages and divorces etc.
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19. Mortality rates

20. Crude death rate
 It is defined as "the number of deaths (from all
causes) per 1000 estimated mid-year population
in one year, in a given place".
 It measures the rate at which deaths are
occurring from various causes in a given
population, during a specified period.
CDR = Number of deaths during the Year
Mid - year population
X l OOO
Dr. Shubhangi Kshirsagar 20

21. Specific death rates
 It may be –
a. Cause or disease specific - e.g., tuberculosis,
cancer, accident
b. Related to specific groups e.g., age specific,
sex-specific, age and sex specific, etc.
 E.g. specific death rate due to tuberculosis
= Number of deaths from TB during a calender year
Mid - year population
X l OOO
Dr. Shubhangi Kshirsagar 21

22. Infant mortality rate
Number of all death of children less than 1 year
of age in a year
Number of live birth in the year
Maternal mortality rate (MMR)
Total no. of female death due to complication of pregnancy/
child birth or within 42days of delivery from puerperal
causes in an area during a given year
Total number of live births in the same area and year
Dr. Shubhangi Kshirsagar 22
X l OOO
or 1 lac
X l OOO

23. Case fatality rate
= Total number of deaths due to a particular disease
Total number of cases due to the same disease
 It represents the killing power of a disease.
 It is simply the ratio of deaths to cases.
 Case fatality rate is typically used in acute
infectious diseases (e.g., food poisoning,
cholera, measles).
 The case fatality rate for the same disease may
vary in different epidemics because of changes
in the agent, host and environmental factors.
X l OO
Dr. Shubhangi Kshirsagar 23

24. Proportional mortality rate (Ratio)
 It is sometimes useful to know what proportion
of total deaths are due to a particular cause (e.g.,
cancer) or what proportion of deaths are
occurring in a particular age group (e.g., above
the age of 50 years).
 Proportional mortality rate expresses the
"number of deaths due to a particular cause (or in
a specific age group) per 100 (or 1000) total
deaths".
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25. a. Proportional mortality from a specific disease
Number of deaths from the specific disease in a year
Total deaths from all causes in that year
b. Under-5 proportionate mortality rate
No. of deaths under 5 years of age in the given year
Total number of deaths during the same period
c. Proportional mortality rate for aged 50 years and above
Number of deaths of persons aged 50 years and above
Total deaths of all age groups in that year
Dr. Shubhangi Kshirsagar
X l OOO
X l OOO
X l OOO
25

26. Morbidity rates
Dr. Shubhangi Kshirsagar 26

27. Morbidity rates
 Definition - "any departure, subjective or objective,
from a state of physiological well-being“
 The term is used equivalent to such terms as
sickness, illness, disability etc.
 The WHO Expert Committee on Health Statistics
noted in its 6th Report that morbidity could be
measured in terms of 3 units
 persons who were ill
 the illnesses (periods or spells of illness) that these
persons experienced
 the duration (days, weeks, etc) of these illness
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28.  Three aspects of morbidity are commonly
measured by morbidity rates or morbidity
ratios, namely frequency, duration and severity.
1. Disease frequency is measured by incidence
and prevalence rates.
2. The average duration per case or the disability
rate, which is the average number of days of
disability per person, may serve as a measure
of the duration of illnesses.
3. The case fatality rate may be used as an index
of severity.
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29. Incidence
 Definition - “The number of NEW cases
occurring in a defined population during a
specified period of time.”
Number of NEW cases of specific
disease during a given time period
Population at risk during that period
 Obtained from disease register or cohort study
or trial.
Dr. Shubhangi Kshirsagar
X l OOO
=
29

30. Special incidence rates
 Examples include: Attack rate (case rate),
Secondary attack rate, Hospital admission rate,
etc.
 Attack rate – It is an incidence rate (usually
expressed as a per cent), used only when the
population is exposed to risk for a limited period
of time such as during an epidemic.
Number of new cases of a specified
disease during a specified time interval
Total population at risk during the same interval
Dr. Shubhangi Kshirsagar
X l OOO
=
30

31. b. Secondary attack rate
It is defined as the number of exposed persons
developing the disease within the range of the
incubation period following exposure to a primary
case.
Uses of incidence rate
It is useful for taking action -
 To control disease
 For research into aetiology and pathogenesis,
distribution of diseases, and efficacy of preventive
and therapeutic measures.
Dr. Shubhangi Kshirsagar 31

32. Prevalence
 Definition - “The total number of all individuals
who have an attribute or disease at a particular
time (or during a particular period) divided by the
population at risk of having the attribute or
disease at this point in time or midway through
the period’’
 Includes all current cases (old & new)
 Obtained from cross-sectional studies or disease
registers
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33. Fertility rates

34. Fertility rates
a. Birth rate
Number of live births during the year
Estimated mid year population
b. General fertility rate
No. of live birth in an area during the year
Mid year female population age 15-44 in same area
in same year
Dr. Shubhangi Kshirsagar
X l OOO
X l OOO
=
=
34

35. c. Marriage rate
Number of Marriages in the year
Mid year population
Dr. Shubhangi Kshirsagar
X l OOO
=
35

36. Thank You