POPULATION SURVEYSPOPULATION SURVEYS Evaluation the health status of a Evaluation the health status of a

population (community diagnosis).population (community diagnosis). Information about the distribution of Information about the distribution of

health problemshealth problems Provides fundamental basis for Provides fundamental basis for

planning and managing needed planning and managing needed servicesservices

To investigation of factors affecting To investigation of factors affecting health and diseases, e.g., health and diseases, e.g., environment, occupation, income, environment, occupation, income,

Helpful for studying the natural history, Helpful for studying the natural history, etiology and risk factors for a diseaseetiology and risk factors for a disease

Pop. surveysPop. surveys

Related to administration of Related to administration of health services health services

use of health servicesuse of health servicesexpenditure on healthexpenditure on healthevaluation of population health evaluation of population health needs and unmet needsneeds and unmet needs

evaluation of medical care, etcevaluation of medical care, etc

HEALTH SURVEYSHEALTH SURVEYS Any survey relating to any aspect of healthAny survey relating to any aspect of health

Aim is to derive information from a group/house Aim is to derive information from a group/house hold.hold.

all types of information, social, economical, all types of information, social, economical, morbidity, births etc.morbidity, births etc.

OBSERVATIONALOBSERVATIONAL Descriptive studiesDescriptive studies

Cross sectional studiesCross sectional studies Longitudinal studiesLongitudinal studies

Analytical studiesAnalytical studies Case control studyCase control study Cohort studyCohort study Cross sectional studiesCross sectional studies

EXPERIENTAL STUDIESEXPERIENTAL STUDIES Randomized control trialsRandomized control trials Field trialsField trials Community trialsCommunity trials

SURVEY METHODSSURVEY METHODS

Health interview (face to Health interview (face to face )surveysface )surveys

Health examination surveysHealth examination surveys

Health record surveysHealth record surveys

Mailed questionnaire surveysMailed questionnaire surveys

QUESTIONNAIRE:QUESTIONNAIRE:

A questionnaire is an inquiry form A questionnaire is an inquiry form containing a set of questions to which containing a set of questions to which answers of the informants are obtained. answers of the informants are obtained.

Questionnaire is simply that it is sent out Questionnaire is simply that it is sent out by mail, by mail,

Schedule is taken personally by an Schedule is taken personally by an interviewer or enumerator to the interviewer or enumerator to the informant to get filled in a face-to face informant to get filled in a face-to face inquiry. inquiry.

QUESTIONNAIREQUESTIONNAIRE Should be so simple that each must be Should be so simple that each must be

able to understand and answerable to understand and answer Questions are so arranged that they Questions are so arranged that they

can be easily answeredcan be easily answered Should be so designed that objective Should be so designed that objective

answers are forthcominganswers are forthcoming Questions should be very politeQuestions should be very polite Questions concerning personal Questions concerning personal

mattersmatters should be tactfully handledshould be tactfully handled Instructions must be accompaniedInstructions must be accompanied Sufficient space for answeringSufficient space for answering

RESEARCHRESEARCH

Systematic quest for undiscovered truthSystematic quest for undiscovered truth A manner in which men / women solve A manner in which men / women solve

the knotty problemsthe knotty problems An organized systematic data based on An organized systematic data based on

critical, scientific inquiry into a specific critical, scientific inquiry into a specific problem undertaken with the objective problem undertaken with the objective of finding answers or solutions to itof finding answers or solutions to it

Research provides reliable & accurate Research provides reliable & accurate information for suitable making & information for suitable making & planning planning

1. Basic Research1. Basic Research

Is necessary to generate newIs necessary to generate new

knowledge and technology and toknowledge and technology and to

improve existing knowledgeimprove existing knowledge..

2. Applied Research 2. Applied Research

Is necessary to identify priority Is necessary to identify priority problems & to design & evaluate problems & to design & evaluate policies and program that will deliver policies and program that will deliver the greatest Health benefits, making the greatest Health benefits, making optimal use of available resources optimal use of available resources and knowledge. and knowledge.

Research provides reliable & Research provides reliable & accurate information for suitable accurate information for suitable making & planningmaking & planning

OBJECTIVES OF RESEARCHOBJECTIVES OF RESEARCH

To know health related problems, To know health related problems, needs, priorities, sources, options, needs, priorities, sources, options, Cost effectiveness.Cost effectiveness.

To verify usefulness of basic research To verify usefulness of basic research in different demographic conditions.in different demographic conditions.

Decision making after information Decision making after information especially where information is especially where information is inadequate & lacking inadequate & lacking

Appropriate policies & programs Appropriate policies & programs organizing & implementationorganizing & implementation..

ADVANTAGES OF DOING RESEARCHADVANTAGES OF DOING RESEARCH

Provide extensive reading & knowledgeProvide extensive reading & knowledge Helps in selecting a research problem Helps in selecting a research problem

for professional field.for professional field. Provides an opportunity to do Provides an opportunity to do

significant independent worksignificant independent work Provide opportunities to publish Provide opportunities to publish

observations and show knowledge in a observations and show knowledge in a scientific manner.scientific manner.

STATISTICSSTATISTICS Measured or counted facts or information.Measured or counted facts or information. Science of figures.Science of figures. Numerical facts in any field of study.Numerical facts in any field of study.

Statistics are aggregates of facts which are Statistics are aggregates of facts which are expressed in numerical formexpressed in numerical form

It is a field of study concerned with It is a field of study concerned with

techniques or methods of collection of techniques or methods of collection of data, classification, Summarizing, data, classification, Summarizing, interpretations, drawing inferences, testing interpretations, drawing inferences, testing hypothesis, making recommendations hypothesis, making recommendations when only a part of data is used.when only a part of data is used.

Statistics:Statistics:

Is science of comprising, classifying Is science of comprising, classifying & tabulating numerical data & & tabulating numerical data & expressing results in a mathematical expressing results in a mathematical or graphical form.or graphical form.

Biostatistics:Biostatistics:

That branch of statistics concerned That branch of statistics concerned with mathematical facts and data with mathematical facts and data relating to biological eventsrelating to biological events

BIOSTATISTICSBIOSTATISTICS

Is a term used when tools of Is a term used when tools of statistics are applied to the data statistics are applied to the data that is derived from biological that is derived from biological sciences.sciences.

BP – recorded in figuresBP – recorded in figures Enlargement of spleen, death Enlargement of spleen, death

rate due to TB, typhoid fever etc.rate due to TB, typhoid fever etc. Define variability in an attribute Define variability in an attribute

or a character due to a chance or or a character due to a chance or normal & if there is a pathology normal & if there is a pathology or abnormal.or abnormal.

BIOSTATISTICSBIOSTATISTICS

Draw conclusions about the whole by Draw conclusions about the whole by selecting only a part from the whole selecting only a part from the whole on sample basis. Major area of on sample basis. Major area of statistics today is concerned with statistics today is concerned with drawing conclusions about the whole drawing conclusions about the whole from the sample and testing the from the sample and testing the reliability of the results draw from reliability of the results draw from the sampl the sampl

Uses of BiostatisticsUses of Biostatistics To define what is normal or abnormal in a To define what is normal or abnormal in a

population & define limits of normality.population & define limits of normality. To find the difference between means & To find the difference between means &

proportions at two places or periodsproportions at two places or periods To find Correlation / association between To find Correlation / association between

two variables / attributes.two variables / attributes. To find action of action.To find action of action. To compare action of different drugs.To compare action of different drugs. To find relative potency of a new drugTo find relative potency of a new drug To compare different lines of treatment.To compare different lines of treatment. To test usefulness of vaccines & Antisera To test usefulness of vaccines & Antisera Role of causative factors Role of causative factors Effects of health programmes.Effects of health programmes.

Uses of StatisticsUses of Statistics

Statistics simplifies complexitiesStatistics simplifies complexities Statistics presents facts in a definite formStatistics presents facts in a definite form Statistics simplifies comparison of dataStatistics simplifies comparison of data Statistics studies relationships among Statistics studies relationships among

different factorsdifferent factors Statistics studies changes in the level of a Statistics studies changes in the level of a

given phenomenongiven phenomenon Statistics aids forecastingStatistics aids forecasting Statistics guides the formulation of Statistics guides the formulation of

policies.policies. Statistics tests the laws of other sciencesStatistics tests the laws of other sciences

CHARACTERISTICS OF BIOSTATISTICSCHARACTERISTICS OF BIOSTATISTICS

Statistics are aggregates of factsStatistics are aggregates of facts Statistics are numerically expressedStatistics are numerically expressed Statistics are enumerated or estimated Statistics are enumerated or estimated

according to reasonable standards of accuracyaccording to reasonable standards of accuracy Statistics are collected in a systematic mannerStatistics are collected in a systematic manner Statistics are collected with a definite object in Statistics are collected with a definite object in

view view Statistics are capable of being placed in relation Statistics are capable of being placed in relation

to each other so that they are comparable to each other so that they are comparable

VARIABLEVARIABLE

a characteristic of interest in a characteristic of interest in a study that has different a study that has different values for different persons, values for different persons, places or things.places or things.

A quantity that varies within A quantity that varies within limitslimits

CONSTANTCONSTANT

A quantity that does not vary. They A quantity that does not vary. They do not do not

require statistical study. require statistical study.

POPULATIONPOPULATION

It is an entire group of people or It is an entire group of people or study elements, persons, things or study elements, persons, things or measurements.measurements. It consist of totality It consist of totality of observation with which we are of observation with which we are concerned.concerned.

finitefinite infiniteinfinite

SAMPLESAMPLE

It is a part of a populationIt is a part of a population It is a group of sampling units that It is a group of sampling units that

form part of a populationform part of a population It is a subset of populationIt is a subset of population

PARAMETERPARAMETER

Any numerical value describing a Any numerical value describing a characteristics of a POPULATION characteristics of a POPULATION is called a parameteris called a parameter

STATISTICSTATISTIC

Any numerical value Any numerical value describing a characteristics of describing a characteristics of a sample is called a statistica sample is called a statistic

DATADATA

consist of discrete observation of an consist of discrete observation of an attribute or event that carries little attribute or event that carries little meaning when considered alone.meaning when considered alone.

Data is transformed into information Data is transformed into information by reducing them, summarizing them by reducing them, summarizing them & adjusting them for variation.& adjusting them for variation.

Data are analyzed to assess changes Data are analyzed to assess changes in diseases and health situations in a in diseases and health situations in a community. community.

Qualitative Data:Qualitative Data:

There is no notion of magnitude or There is no notion of magnitude or size of a characteristic or attribute as size of a characteristic or attribute as the same can’t be measured. the same can’t be measured.

There is only one variable.There is only one variable. attacked, diet, cured, vaccinate, attacked, diet, cured, vaccinate, Males or femalesMales or females

VARIABLE IS DISCRETEVARIABLE IS DISCRETE

QUANTITATIVE DATAQUANTITATIVE DATA

It has a magnitude It has a magnitude there are two variables, there are two variables,

characteristics and frequency. characteristics and frequency. The variable is CONTINUOUSThe variable is CONTINUOUS

Classification of dataClassification of data

Become conciseBecome concise Arouse interest of readerArouse interest of reader Become simple and meaningfulBecome simple and meaningful needs few words to explainneeds few words to explain Define a problem & suggest solutionDefine a problem & suggest solution Helpful for further analysisHelpful for further analysis