Morbidity and Mortality 29 Repaired)

8/9/2019 Morbidity and Mortality 29 Repaired)

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MORBIDITY

ANDMORTALITY

SUBMITTED TO:- SUBMITTED BY:-

Mrs . Sabitha Nayak Ms.Shesly P.Jose

PROF & HOD Of OBG Dept I Year MSc Nursing

NUINS-CON NUINS-CON

SUBMITTED ON:-16-03-2010


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MORBIDITY AND MORTALITY

INTRODUCTION:-

Health is essential to socioeconomic development of has gained increasing recognition. Indicators arequired to measure the health status of the community, to compare the health status of a country ,for assessme

of health needs, for allocation of source resources; and for monitoring and evaluating the health resource

activities and programmes . Variables will help to measure the changes in health status.

INDICATORS OF HEALTH:-

The indicators of health may be classified as follows:

i. Mortality indicators

ii. Morbidity indicators

iii. Disability ratesiv. Nutritional status indicators

v. Health care delivery indicators

vi. Utilization ratesvii. Indicators of social and mental health

viii. Environmental indicators

ix. Socioeconomic indicatorsx. Health policy indicators

xi. Indicators of quality of life

xii. Other indicators

MORTALITY :-

Mortality is the condition of being mortal, or susceptible to death; the opposite of immortalityEpidemiologist often starts the investigation of health experience of a population with information that i

routinely available many countries the fact and cause of death are recorded on a standard death certificate, which

also carries information on age ,sex , date of birth and place of residence.

MEASUREMENT OF MORTALITY:-

Traditionally and universally , most epidemiologic studies begin with mortality data. Mortality dat

provide the standing point for many epidemiologic studies.

Who mortality data base documentation :-

The WHO Mortality Data base comprises deaths registered in national vital registration systems, with

underlying cause of death as coded by the relevant national authority. Underlying cause of death is defined as thedisease or injury which initiated the train of morbid events leading directly to death, or the circumstances of the

accident or violence which produced the fatal injury in accordance with the rules of the Internationa

Classification of Diseases.
http://en.wikipedia.org/wiki/Deathhttp://en.wikipedia.org/wiki/Immortalityhttp://en.wikipedia.org/wiki/Deathhttp://en.wikipedia.org/wiki/Immortality


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The database contains number of deaths by country, year, sex, age group and cause of death as far back

from 1950. Data are included only for countries reporting data properly coded according to the InternationaClassification of Diseases (ICD).

The basis for mortality data is Death certificate. For ensuring national and internationa

comparability , it is very necessary to have a uniform and standardized system of recording and classifying death

The international death certificate is in two parts. Part I deals with the immediate cause and theunderlying cause which started the whole trend of events leading to death. The underlying cause of death i

recorded in line C. in the example cited , the underlying cause of death is strangulated hernia. After operation

the patient developed bronchopneumonia as a complication and ended in death. In the part two is recorded anysignificant associated disease that contribute to the death but did not directly lead to death.

Death certificate in India:-

In order to improve the quality of maternal mortality and infant mortality data and to provide

alternative method to collect data on death during pregnancy and infancy , a set of questions are added to thebasic structure of international; death certificate for use in India.

Limitation in mortality data:-

Incomplete reporting of death Lack of accuracy

Lack of uniformity

Choosing a single cause of death

Changing coding system and changing fashion in diagnosis

Diseases with low vitality

Uses of mortality data:-

In explaining trends and differentials in overall mortality

bronchopneumonia

Strangulated hernia

diabetes


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total population: 69.89 yearsmale: 67.46 yearsfemale: 72.61 years (2009 est.)

Year Life expectancy atbirth

Rank Percent Change Date of Information

2004 64.35 162 1.15 % 2004 est.

2005 64.35 162 0.00 % 2005 est.

2006 64.71 162 0.56 % 2006 est.

2007 68.59 144 6.00 % 2007 est.

2008 69.25 144 0.96 % 2008 est.

2009 69.89 144 0.92 % 2009 est.

Infant and maternal mortality rate (IMR & MMR) :-

Two of the specific death rates are used immensely as valuable indicators of the state advancement o

any country. They are the infant mortality rate and maternal mortality rate. The reason for such reputation are

due to the high relationship noted between the high rate of death among the infants ( and mothers) are poorstandards of living. Raising the standard of living in terms of literacy and improvement in sanitation has had

tremendous impact on reducing these death rates.

o IMR=no: of death under 1yr age during 1yr 1000

No: of live birth during that year

India Infant mortality rate

Infant mortality rate: total: 30.15 deaths/1,000 live births

male: 34.61 deaths/1,000 live births

female: 25.17 deaths/1,000 live births (2009 est.)

Year Infant

mortalityrate

Rank Percent

Change

Date of Information

2003 59.59 59 2003 est.

2004 56.29 56 -5.54 % 2004 est.

2005 56.29 55 0.00 % 2005 est.


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2006 54.63 55 -2.95 % 2006 est.

2007 34.61 73 -36.65 % 2007 est.

2008 32.31 72 -6.65 % 2008 est.

2009 30.15 72 -6.69 % 2009 est.

The denominator consist of live ( or viable) birth only. This rate may be further considered in terms

infant dying under 28 days of age (neonates)and those dying between the ages of 28days to 1 below year(poneonates ).

Neonatal = no of death ,under 28 days of age occurred during a year 1000

mortality rates no of live birth during that year

Since there are distinct differences between the causes of death among neonates and post neonates the above decision provides a more sensitive way of studying the infant mortality. When infant mortality decreaseand living standards improves , the impact is shown much more on the post neonatal death than on neonatal death

Jouranal study -1

Neo-natal mortality high in India, says UNICEF ( Ruchi Gupta)

New Delhi, Dec 10 (ANI): Neonatal mortality or death within 28 days of birth is high in India, according

to the latest UNICEF report.

According to the UNICEFs statistical review Progress for Children-A World Fit forChildren, out of the estimated 2.1 million child-mortality (death of children in their first five years of

life) in India, one million are during the neonatal period (within 28 days of birth).

Malnutrition underlines up to half of under-five deaths globally, followed by neonatal causes in

37 percent of cases, pneumonia (19 pc), diarrhea (17 pc), malaria (8 pc), measles (four pc), injuries (three

pc), AIDS (three pc) and other reasons (10 pc). Pneumonia kills more children than any other illness -

more than AIDS, malaria and measles combined. Around one in every five under-five children globally

die from the disease. India has the largest number of deaths due to pneumonia. In 2006, for the first

time in the world, the number of children dying before their fifth birthday fell below 10 million to 9.7

million, the report said.

India with 2.1 million under-five child deaths, contributes to about 21 percent of the global

burden of child deaths. India has the largest pool of 9.4 million children, who have never been

immunised in the world.

A UNICEF representative said, Immunisation in the 80s and 90s was shining in India. After that

it has seen a progressive decline. While in the weaker states such as Bihar, Madhya Pradesh and Rajasthan

the immunisation programme improved, in the well-performing states, such as Gujarat and Maharashtra

they showed a decline. So, the overall decline,


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The representative suggested the need for strengthening the immunisation system, which includes

preservation of vaccine at right temperature, distribution of vaccines from the Centre to States, and

education of health workers. While safe drinking water is essential for child survival, the world is on the

track to meet the Millennium Development Goal (MDG) on safe drinking water. With 84.5 percent rural

and 95 percent urban population having sustainable access to safe drinking water, India is also on the track

to meet this goal.

The report acknowledges that progress of India, which is one of the largest countries of the world,

is key to achieving the MDGs. With 20 per cent of the worlds children under age of five years,

India needs at least 20 percent of the worlds attention. And, it is getting it, said UNICEFIndiarepresentative Gianni Murzi. (ANI)

Jouranal study- 2

Title: Infant and childhood mortality in India. Mahadevan, K., Murthy, M. S. R.,Reddy, P. R., Reddy,

P. J.,Sivaraju, S., Gowri, V.

The differential trends in infant and child mortality, and their major determinants were studied in asample of 3000 households representing 3 religious and caste groups in Chittoor district, Andhra Pradesh,

India. The highest rate of infant and child mortality was found among the Muslims and Harijans, while the

caste Hindus showed the lowest rate. Infant and child mortality was determined by socio-economicfactors, particularly education and income, housing pattern, age at marriage, number of living children,

prelacteal feeds and breast feeding, and maternal anaemia. Tetanus neonatorum, asphyxia, delivery

problems, diarrhoea and dysentery were influencing mortality. Infant and child malnutrition and

prematurity were other causes of mortality. A reciprocal relationship between infant mortality and fertilitywas observed. The determinants varied for instant and child mortality. The conclusion reached is that

while biological and family factors affected infant mortality, family and environmental factors affect early

childhood mortality.
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Chart 4: India's Infant

Mortality Rate, Year 2000 2005

MMR = no of female death from pregnancy,child birth,or Peuperium in a year 1000

no of live birth during that year

Maternal death is defined as the death of a woman while pregnant or with in 48 days of termination o

pregnancy irrespective of the duration ,and the site of pregnancy from any cause related to or aggravated to by th

pregnancy or its management but not from accidental or incidental causes.
http://www-personal.umich.edu/~sankum/images/India_Infant_Mortality.jpg


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Journal study

Changing trends in maternal mortality over a decade By Y. Juneja , a, U. Goela and M.New Delhi, India

To study the change in trend in maternal mortality over the last decade and to find outspecific causes of death. Method: A retrospective study was carried out. The admission ledgers of patients

admitted over two 3-year periods (19791981 and 19891991) were studied to ascertain the total number of

maternal deaths and the specific causes of death.Results: One hundred fifty-eight deaths occurred during 1979

1981 and 149 deaths during 19891991. During the same period ther were 23 098 and 37 763 total births,

respectively, the overall maternal mortality rate thus significantly declining from 684/100 000 total births in19791981 to 394/100 000 total births in 19891991. Sepsis followed by hemorrhage and hepatitis were the

leading causes of maternal deaths over the decade. Conclusion: Health education and availability of healthservices, largely at a community level, would contribute to reducing the incidence of preventable causes of

maternal deaths such as sepsis and hemorrhage.

Fetal death rates:-

The stillbirth or fetal deaths do not enter into the calculation of the usual mortality rates. The WHO

subdivided the fetal death based on gestation as follows :

Early :under 20 weeks

Intermediate :20 to 27 weeks

Late :28 weeks and over

The still birth rate(late fetal death rate) correspond to


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Still birth no of fetal death ,28wks of gestation or more occurred during a year 1000

rate =no of live birth plus late fetal death during that year

An early fetal death rate may also be computed ,but full information on early death are usually not

easily available. Some times a ratio is also calculated which is defined as:

Late foetal death=no of foetal death,28 week of gestation Or more occurred during a year 1000

rate No of live births during that year

Child mortality rate (under 5 mortality rate):-

Another indicator related to the over all health status is the early childhood (1 -4yrs) mortality rate. It

is defined as the number as the number of death at age 1-4 yrs in a given year ,per 1000 children in that agegroup at the midpoint of the year concerned . it thus excludes infant mortality.

YearValue

1990 123

1995 104

2000 94

2005 74

Children under five mortality

rate per 1,000 live births

(India )


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Child survival index :-

A child survival rate per 1000 birth can be simply calculated by subtracting the under 5 mortality rate

from 1000 diving this figure by ten shows the percentage of those who survive to the age of 5yrs

Child survival rate 1000 under 5 mortality rate

country 1960 1996

India 76.1 90.1

srilanka 87.0 98.1

China 79.1 95.7

USA 97 99.1

Under 5 propotionate mortality rate:-

It is the proportion of total death occurring in the under 5 age group . This rate can be used to reflect both

infant and child mortality rate . In communities where sanitation is poor the proportion may exceed to 60%

Disease specific mortality :-

Mortality rates can be computed for specific diseases. As countries begin to extricate themselves from

burden of communicable disease, a number of other indicators such as death from cancer , cardiovascular

disease, accidents, diabetes etc have emerged as measures of specific disease problem.

Propotional mortality rate :-


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The simplest measure of estimating the burden of a disease in the community is proportional mortality

rate.. ie, the proportion of all death currently attributed to it. For example CHD is the cause of 25-35% of alldeath in most western countries

Case fatality rate:-

= total no of death due to a particular disease 100

total no of cases due to a same disease

It determines the killing power of a disease

It is simply the ratio of death to case

It is typically used in acute infectious diseases( eg: food poisoning, cholera etc)

Specific mortality rate:-

This rate can be made specific with regard to any subgroup of the population such as age specific death rate

for group A or sex specific death rate for sex M or cause specific death rate for cause C. A refers to a specific

age; C refers to specific cause of death; M and F refers to their gender .

One can also make the rates specific for combination of different subgroups .

Age specific death rate = no of death of age A in an year 1000

For group A estimated population of age A midyear

sex specific death rate = no of death of sex M in an year 1000 .

for Age M estimated population of sex M midyear

Cause specific = no of death due to cause C occured in a year 1000

rate estimated mid year population at

Instead of expressing these specific rates per 1000 population a figure of 10,000 or 1,00,000 maybe used to avoid fractions in the quotient.

AGE-SPECIFIC ANALYSIS OF REPORTED MORBIDITY IN KERALA, INDIA

(T.R. Dilip, Lecturer, Centre for Development Studies, Ulloor Trivandrum, India)

This study attempts to provide a wider understanding of the differentials in reported health status

in Kerala, while comparing morbidity in the state with other regions in the Indian subcontinent. Reportedmorbidity and the duration of life lived with a disease is higher in Kerala. Economic inequalities were found

only in late-working ages and the elderly, primarily due to higher prevalence of life style-associated chronic

conditions in these two age groups. Significant caste-wise differences among adolescents and prime workingages indicated potential for health problems induced by income deprivation in socially disadvantaged

subgroups. Self-reported morbidity was 65% higher than proxy-reported morbidity. Regional differences were

significant across all age groups, with high morbidity in the most developed region in the state. Results alsosuggested the need to factor for self- and proxy-reported status in any analysis of morbidity using similar

survey data.

AHRQ( Agency for Healthcare Research and Quality):-
http://www.ahrq.gov/http://www.ahrq.gov/


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There is increasing interest in deploying and publicly reporting a risk-adjusted measure of

mortality as a quality indicator of hospital system-level performance. Government agencies, policymakers,

health care systems, and consumers are grappling with critical issues regarding the attributes, relative merits,

interpretation, and potential uses of existing measurement methods to drive improvement and inform choice.

The presentations provided here are from a November 2008 meeting to discuss issues related to mortality

measures.

Hospital Standardized Mortality Measurement:-

The Agency for Healthcare Research and Quality (AHRQ) and the Institute for Healthcare Improvement

(IHI) have partnered to explore the scientific controversies around using a mortality measurement

methodology to improve health care quality. The mortality measures would also be used to help track and

reduce mortality nationally and in individual institutions.

In November 2008, AHRQ and IHI convened a meeting in Cambridge, Massachusetts, to discuss these

important issues. Presentations and discussion took place on five existing risk-adjusted mortality measures. In

addition, experts reviewed issues related to:

The lessons learned from past government efforts to publicly report mortality rates.

The National Quality Forum's (NQF) intent to vet a national mortality measure or measures. The pros and cons of including deaths occurring within 30 days of hospital discharge.

The progress in measuring diagnosis-specific mortality rates.

In addition, ongoing research to include automated clinical data in risk-adjustment methods was

presented, and research needs were outlined .

Adjusted or standardized rates:-

Astandardized death rate is a crude death rate that has been adjusted for differences in agecomposition between the region under study and astandardpopulation. Standardization allows for

comparisons when the population structures differ and is key in assessing the potential influence of

environmental or cultural factors on death rates in a region.There are two ways of computing standardizeddeath rates direct and indirect standardization. The results will be a little bit different. The one you would

use varies based on the data available to you.

Direct Standardization (SDR1) calculates a weighted average of the regions age-specific mortality

rates where the weights represent the age-specific sizes of thestandardpopulation.

Indirect Standardization (SDR2) uses age-specific mortality rates from thestandardpopulation to

derive expected deaths in the regions population.

Direct Standardization:

SDR1 = [ age groups (Mar Pas)]/Ps x 1000

Mar is the age-specific mortality rate for the region.

Pas is the number of people in the age group in the standard population.

Ps is the total standard population.

To compute the direct standardized mortality rate:


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1. For each age group, you need to multiply Mar by Pas.

2. Add them up.

3. Divide the sum by the total standard population.

4. Multiply by 1000, or give the rate in terms of "per thousand population."

Indirect Standardization:

SDR2 = Dr/[ age groups (Mas Par)] x CDRs

Mas is the age-specific mortality rate for the standard population.

Par is the number of people in the age group in the regions population.

Dr is the number of deaths in the region.

CDRs is the crude death rate for the standard population.

To compute the indirect standardized mortality rate:

1. For each age group, you need to multiply Mas by Par.

2. Add them up.

3. Divide the sum into the number of deaths in the region.

4. Multiply by the crude death rate.

Choosing which formula to use will depend on what data you have access to. More typically, the data you have

will be the components for indirect standardization. You are more likely to be able to find age-specific

mortality rates for a standard population than for a specific region such as a state.In this case, since I have

given you state population data in thousands, you will need to divide your final result by 1,000.

MORBIDITY

Morbidity has been defined as any departure, subjective or objective , from a state of

physiological well being . the problem is 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- a. person who ill ; b.the illness that these persons experienced and c. the duration of these illness.

Three aspect of morbidity are commonly measured by morbidity rates and morbidity ratios,

namely frequency duration and severity. Disease frequency is measured by incidence and prevalence rate . the

average duration per per case or the disability rate , which is the average number of the days of disability perperson, may serve as a measure of the duration of illness. The fatality rate may be used as an index of severity.

This section focus on incidence and prevalance rate , which are widely used to describe disease occurrence in a

community.


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The value of morbidity data may be summarized as follows ;

They describe the nature and extend of the disease load in the community and thus assist in the

establishment of priorities

They usually provide more comprehensive and more accurate and clinically relevant information on

patient characteristic than can be obtained from morbidity data and are therefore essential for basicresearch.

They act as starting points for aetiological studies, and thus play a crucial role in disease prevention

They are needed for monitoring and evaluation of disease control activities

Morbidity indicators:-

To describe health in terms of mortality is rates only is misleading. This is because the mortality

indicators donot reveal the burden of illhealth in a community , as for example mental illness and rheumatoid

arthritis . Therefore morbidity indicators are used to supplement mortality data to describe the health status of apopulation. Morbidity statistics have also their own drawback; they tend to overlook a large number of condition

which are subclinical or inapparent , that is , the hidden part of the iceburg of disease.

The following morbidity rates are used for assessing the illhealth in the community.


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1. Incidence and prevalence

2. Notification rates3. Attendance rate at outpatient department, health centres ,etc

4. Admission readmission and discharge rates

5. Duration in hospital and Spells of sickness or absence from work or school

Incidence :-

This is based on the number of cases of disease appearing in a stated period of time divided by theestimated population at midpoint of this time period . Usually this is defined as : the number

of NEW cases occurring in a defined population during a specified period of time. It is given by the formula

=no of new caseof specific disease during given time period 1000

Population at risk during that period

For example , if there had been 500 new cases of an illness in a population of 30,000 in a year , the incidencerate would be

=500/30,0001000

=16.7per 1000 per year

Note: incidence rate must include the unit of time used in the final expression . If you wrote 16.7per 1000,this would be inadequate. The correct expression is 16.7 per1000per year.

It will be seen from the above definition that the incidence rate refers

a) Only to new cases

b) During a given period(usually one year)

c) In a specified population or population at risk ,unless other denominators are chosend) It can also refer new spells or episodes of disease arising in a given period of time , per 1000

population. For example , a person may suffer from common cold more than once a

e) year . If he had suffered twice , he would contribute two spell of sickness in the year. The formula inthis case would be

Incidence =no of spells of illness of starting in a defined period 1000

rate mean no of perspn exposed to risk in that period

Incidence measures the rate at which new cases are occurring in a population . It is not influenced by the

duration of the disease . the use of incidence is generally restricted to acute conditions.

Special incidence rates :-


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Examples include : attack rate( case rate) , secondary attack rate , hospital admission rate, etc

Attack rate

An attack rate is an incidence rate (usually expressed as a percent) , used only when the population

is exposed to a risk for a limited period of time such as during an epidemic. It relates the number of cases in

the population at risk and reflect the extend of the epidemic.

Attack rate

=no of new case of a specified disease during specified time100 total

population at risk during that period

Incidence or attack rates can be made specific in terms of some particular attributes such as age ,

sex, occupation, cause etc

Secondary attack rate:-

It is defined as the number of exposed persons developing the disease with in the range of incubationperiod following exposure to a primary case.

Uses of incidence rate:_

The incidence rate as an indicator of health status , is useful for taking action

i. To control disease

ii. For research into etiology and pathogenesis , distribution of disease , and efficacy o

preventive and therapeutic measures.

For instance , if the incidence rate is increasing ,it might indicate failure or ineffectiveness of the currencontrol programmes. Rising incidence rate may suggest the need for a new disease control or preventive

programme, or that reporting practice had improved. A change or fluctuation in the incidence of disease may also

mean a change in the etiology of disease,eg; change in the agent , host and environment characteristics. Analysiin the difference in incidence rates reported from various socioeconomic groups and geographical areas may

provide useful insights into the effectiveness of the health services provided.

Prevalence:-

The term disease prevalence refers specifically to all current cases( old and new) existing at a

given point of time , or over a period of time in a given population. A broader definition of prevalence is asfollows:

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 .

Although referred to as a rate , prevalence rate is really a ratio. Prevalence is of two type;

Point prevalence

Period prevalence


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Point prevalence:-

Point prevalence of a disease is defined as the number of all current cases ( old and new) existing at agiven point of time in relation to a defined population. The point in point prevalence, may for all practical

purpose consist of a day ,several days or even few weeks depending upon the time it takes to examine the

population sample. It is given by the formula

No of all current cases (old & new)of a specified disease at a given point in time 100

Estimated population at the same point in time

When the term prevalence rate is used , without any further qualification , it is taken to mean point

prevalence which can be made specific for age sex and other relevant factors or attributes.

Period prevalence:-

A less commonly used measure of prevalence is period prevalence. It measures the frequency of all current

cases (old and new) existing during a defined period of time ( eg:- annual prevalence) expressed in relation to adefined population . It includes cases arising before but extending into or through to the year as well as those

cases arising during the year . period prevalence is given by the formula :

=no of existing cases(new& old) of a specific disease during a given period of time interval 100

estimated mid interval population at risk

The term incidence and prevalence are illustrated below

Case1

Case2 case3

Case4

Case5

Case7 case6

Case8

Jan1 dec 31

Start and duration of illness

Incidence would include cases -3,4,5 and8


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Point prevalence (jan1)-1,2,& 7

Point prevalence(dec 31)-1,3,5,&8

Period prevalence(jan- dec ) -1,2,3,4,5,7 & 8

Number of cases of a disease begining , developing and ending during a period of time

Relationship between prevalence and incidence:-

Prevalence depends upon 2 factors , the incidence and duration of illness . given the

assumption that the population is stable , and incidence and duration are unchanging , the relationship betweenincidence and prevalence can be expressed as:

P= I D=incidence mean duration

example (for a stable condition)

incidence = 10 cases per 1000 population per year

mean duration of the disease=5years

prevalence=105 =50 per 1000 population

Conversely , it is possible to derive incidence and duration as follows :

incidence=P/D

duration = P/I

The above equation (P= ID)shows that the longer the duration of disease , the greater its

prevalence. For example , tuberculosis has a high prevalence rate relative to incidence. This is because new

cases of tuberculosis keep cropping up through out the year, while the old ones may persist for months oryears . On the other hand , if the disease is acute and of short duration either because of rapid recovery or

death,the prevalence rate will be relatively low when compared to the incidence rate. In some diseases (eg:food poisoning ), the disease is so short lived , there is no old cases. The same is true of the condition which

are rapidly fatal , such as homicides . strictly speaking , these events have no prevalence. In other words ,

decrease in prevalence may take place not only from a decrease in incidence, but also from a decrease of theduration of illness through either more rapid recovery or more rapid recovery or more rapid death.

When we see a change in prevalence from one time period to another , this can result from

change in incidence, change in duration of disease or both. For example ,improvements in treatment may

decrease the duration of illness and thereby decrease the prevalence of a disease. But if the treatment is such tha

they preventing death, and at the same time not producing recovery, may give rise to theapparently paradoxicaeffects of an increase in prevalence. Further , if duration is decreased sufficiently , a decrease in prevalenc

could take place despite an increase in incidence.

Prevalence has been compared with a photograph , an instantaneous record ; and incidencewith a film , a continuous record. Both the terms may perhaps be better understood by taking into consideration

a coffee house. After the coffee house opens in the morning , people keep entering and leaving , each one

remaining inside the coffee house for a short while . At any point of time , say 10 AM , we could go into thecoffee house and count people over there. This corresponds to estimating the prevalence. The rate at which

people enter the coffee house , say 10 people per hour , is equivalent to the incidence . The relationship between

incidence and prevalence is shown below


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incidence

prevalence

Recovery death

It is important to note the limitations of prevalence rate . It is not the ideal measure for studying disease etiology causation . We hav seen that two factors determining prevalence , namely incidence and duration . Incidence

related to the occurrence of disease and duration to factors which the ourse of the disease.In other words , t

element of duration reflects the prognostic factors ., and incidence reflects the causal factors . Therefore incidenrate should be optimally used in the formation and testing of etiological hypothesis . when incidence rates are n

available , prevalence rates (which are readily obtainable) may have to be used, but the contribution of durati

element always has to be assessed.

Uses of prevalence:_-

Helps to estimate the magnitude of health/ disease problems in the community and iden

potential high risk population

Prevalence rates are especially useful for administrative and planning purpose , eg: hospital b

, manpower needs , rehabilitation facilities ,etc .

Compression of Morbidity Theory

In 1980, Dr. James Fries, Professor of Medicine, Stanford University introduced the compression

of morbidity theory. This theory states that "most illness was chronic and occurred in later life and postulatedthat the lifetime burden of illness could be reduced if the onset of chronic illness could be postponed and if this

postponement could be greater than increases in life expectancy." (Fries, 1980).

Compression of Morbidity Theory
http://endoflife.stanford.edu/M00_overview/Refs.htm#Frieshttp://endoflife.stanford.edu/M00_overview/Refs.htm#Fries


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vii. Bhatia BD et al. A study of perinatal mortality rate from rural based medical college

hospital. Indian Journal of Pediatrics, 1984, 51 ( 409): 165-171.viii. Gupta PK, Gupta AP. Perinatal mortality. Indian Pediatrics, 1985, 22 ( 3): 201-205.

ix. Siddarth Ramji. The National Family Health Survey (NFHS-2)(1) conducted in 1998-99-

childhood mortality. Indian Pediatrics ,March 2001, Vol. 38, Number 3 : 263-266

INTERNET REFERENCE:-

i. Fries J.F. Measuring & monitoring success in compressing morbidity-Annals of Internal

Medicine. Google website;http://www.personnel.unich.edu/images on 24-072009 at 6.00 pmii. Kashif. Idle ramblings of a wandering mind. Google website;

http://www.indexmundi.com/ on 24-072009 at 6.00 pm

iii. Mariam claeson. Bulletin of the World Health Organization .Reducing child mortality in

India in the new millennium . Google website ; http://www.scielosp.org/scielo.php?ing=en on 24-072009 at 6.00 pm

iv. India Infant mortality rate. Google website ; http://www.indexmundi.com/

india/infant_mortality_ rate .htmlv. NFHS Data base that strengthens India s demographic and Health policies and

programmes http://www.nfhsindia.org/

vi. http://www.thaindian.com/newsportal/india-news/neo-natal-mortality-high-in-india-says-

unicef_1008410.html
http://www.personnel.unich.edu/imageshttp://www.personnel.unich.edu/imageshttp://www.personnel.unich.edu/imageshttp://www.blogger.com/profile/06994213058427424271http://www.indexmundi.com/http://www.scielosp.org/scielo.php?ing=enhttp://www.indexmundi.com/%20india/infant_mortality_%20rate%20.htmlhttp://www.indexmundi.com/%20india/infant_mortality_%20rate%20.htmlhttp://www.nfhsindia.org/http://www.thaindian.com/newsportal/india-news/neo-natal-mortality-high-in-india-says-unicef_1008410.htmlhttp://www.thaindian.com/newsportal/india-news/neo-natal-mortality-high-in-india-says-unicef_1008410.htmlhttp://www.personnel.unich.edu/imageshttp://www.blogger.com/profile/06994213058427424271http://www.indexmundi.com/http://www.scielosp.org/scielo.php?ing=enhttp://www.indexmundi.com/%20india/infant_mortality_%20rate%20.htmlhttp://www.indexmundi.com/%20india/infant_mortality_%20rate%20.htmlhttp://www.nfhsindia.org/http://www.thaindian.com/newsportal/india-news/neo-natal-mortality-high-in-india-says-unicef_1008410.htmlhttp://www.thaindian.com/newsportal/india-news/neo-natal-mortality-high-in-india-says-unicef_1008410.html

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