POPULATION SURVEYS Evaluation the health status of a population (community diagnosis). Evaluation the health status of a population (community diagnosis). Information about the distribution of health problems Information about the distribution of health problems Provides fundamental basis for planning and managing needed services Provides fundamental basis for planning and managing needed services To investigation of factors affecting health and diseases, e.g., environment, occupation, income, To investigation of factors affecting health and diseases, e.g., environment, occupation, income, Helpful for studying the natural history, etiology and risk factors for a disease Helpful for studying the natural history, etiology and risk factors for a disease

Pop. surveys Related to administration of health services Related to administration of health services use of health services use of health services expenditure on health expenditure on health evaluation of population health needs and unmet needs evaluation of population health needs and unmet needs evaluation of medical care, etc evaluation of medical care, etc

HEALTH SURVEYS Any survey relating to any aspect of health Any survey relating to any aspect of health Aim is to derive information from a group/house hold. Aim is to derive information from a group/house hold. all types of information, social, economical, morbidity, births etc. all types of information, social, economical, morbidity, births etc. OBSERVATIONAL OBSERVATIONAL Descriptive studies Descriptive studies Cross sectional studies Cross sectional studies Longitudinal studies Longitudinal studies Analytical studies Analytical studies Case control study Case control study Cohort study Cohort study Cross sectional studies Cross sectional studies EXPERIENTAL STUDIES EXPERIENTAL STUDIES Randomized control trials Randomized control trials Field trials Field trials Community trials Community trials

SURVEY METHODS Health interview (face to face )surveys Health interview (face to face )surveys Health examination surveys Health examination surveys Health record surveys Health record surveys Mailed questionnaire surveys Mailed questionnaire surveys

QUESTIONNAIRE: A questionnaire is an inquiry form containing a set of questions to which answers of the informants are obtained. A questionnaire is an inquiry form containing a set of questions to which answers of the informants are obtained. Questionnaire is simply that it is sent out by mail, Questionnaire is simply that it is sent out by mail, Schedule is taken personally by an interviewer or enumerator to the informant to get filled in a face-to face inquiry. Schedule is taken personally by an interviewer or enumerator to the informant to get filled in a face-to face inquiry.

QUESTIONNAIRE Should be so simple that each must be able to understand and answer Should be so simple that each must be able to understand and answer Questions are so arranged that they can be easily answered Questions are so arranged that they can be easily answered Should be so designed that objective answers are forthcoming Should be so designed that objective answers are forthcoming Questions should be very polite Questions should be very polite Questions concerning personal matters Questions concerning personal matters should be tactfully handled should be tactfully handled Instructions must be accompanied Instructions must be accompanied Sufficient space for answering Sufficient space for answering

RESEARCH Systematic quest for undiscovered truth Systematic quest for undiscovered truth A manner in which men / women solve the knotty problems A manner in which men / women solve the knotty problems An organized systematic data based on critical, scientific inquiry into a specific problem undertaken with the objective of finding answers or solutions to it An organized systematic data based on critical, scientific inquiry into a specific problem undertaken with the objective of finding answers or solutions to it Research provides reliable & accurate information for suitable making & planning Research provides reliable & accurate information for suitable making & planning

1. Basic Research Is necessary to generate new Is necessary to generate new knowledge and technology and to knowledge and technology and to improve existing knowledge. improve existing knowledge.

2. Applied Research Is necessary to identify priority problems & to design & evaluate policies and program that will deliver the greatest Health benefits, making optimal use of available resources and knowledge. Is necessary to identify priority problems & to design & evaluate policies and program that will deliver the greatest Health benefits, making optimal use of available resources and knowledge. Research provides reliable & accurate information for suitable making & planning Research provides reliable & accurate information for suitable making & planning

OBJECTIVES OF RESEARCH To know health related problems, needs, priorities, sources, options, Cost effectiveness. To know health related problems, needs, priorities, sources, options, Cost effectiveness. To verify usefulness of basic research in different demographic conditions. To verify usefulness of basic research in different demographic conditions. Decision making after information especially where information is inadequate & lacking Decision making after information especially where information is inadequate & lacking Appropriate policies & programs organizing & implementation. Appropriate policies & programs organizing & implementation.

ADVANTAGES OF DOING RESEARCH Provide extensive reading & knowledge Provide extensive reading & knowledge Helps in selecting a research problem for professional field. Helps in selecting a research problem for professional field. Provides an opportunity to do significant independent work Provides an opportunity to do significant independent work Provide opportunities to publish observations and show knowledge in a scientific manner. Provide opportunities to publish observations and show knowledge in a scientific manner.

STATISTICS 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 expressed in numerical form Statistics are aggregates of facts which are expressed in numerical form It is a field of study concerned with techniques or methods of collection of data, classification, Summarizing, interpretations, drawing inferences, testing hypothesis, making recommendations when only a part of data is used. It is a field of study concerned with techniques or methods of collection of data, classification, Summarizing, interpretations, drawing inferences, testing hypothesis, making recommendations when only a part of data is used.

Statistics: Is science of comprising, classifying & tabulating numerical data & expressing results in a mathematical or graphical form. Is science of comprising, classifying & tabulating numerical data & expressing results in a mathematical or graphical form. Biostatistics: Biostatistics: That branch of statistics concerned with mathematical facts and data relating to biological events That branch of statistics concerned with mathematical facts and data relating to biological events

BIOSTATISTICS Is a term used when tools of statistics are applied to the data that is derived from biological sciences. Is a term used when tools of statistics are applied to the data that is derived from biological sciences. BP – recorded in figures BP – recorded in figures Enlargement of spleen, death rate due to TB, typhoid fever etc. Enlargement of spleen, death rate due to TB, typhoid fever etc. Define variability in an attribute or a character due to a chance or normal & if there is a pathology or abnormal. Define variability in an attribute or a character due to a chance or normal & if there is a pathology or abnormal.

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

Uses of Biostatistics To define what is normal or abnormal in a population & define limits of normality. To define what is normal or abnormal in a population & define limits of normality. To find the difference between means & proportions at two places or periods To find the difference between means & proportions at two places or periods To find Correlation / association between two variables / attributes. To find Correlation / association between 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 drug To 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 Statistics Statistics simplifies complexities Statistics simplifies complexities Statistics presents facts in a definite form Statistics presents facts in a definite form Statistics simplifies comparison of data Statistics simplifies comparison of data Statistics studies relationships among different factors Statistics studies relationships among different factors Statistics studies changes in the level of a given phenomenon Statistics studies changes in the level of a given phenomenon Statistics aids forecasting Statistics aids forecasting Statistics guides the formulation of policies. Statistics guides the formulation of policies. Statistics tests the laws of other sciences Statistics tests the laws of other sciences

CHARACTERISTICS OF BIOSTATISTICS Statistics are aggregates of facts Statistics are aggregates of facts Statistics are numerically expressed Statistics are numerically expressed Statistics are enumerated or estimated according to reasonable standards of accuracy Statistics are enumerated or estimated according to reasonable standards of accuracy Statistics are collected in a systematic manner Statistics are collected in a systematic manner Statistics are collected with a definite object in view Statistics are collected with a definite object in view Statistics are capable of being placed in relation to each other so that they are comparable Statistics are capable of being placed in relation to each other so that they are comparable

VARIABLE a characteristic of interest in a study that has different values for different persons, places or things. a characteristic of interest in a study that has different values for different persons, places or things. A quantity that varies within limits A quantity that varies within limits

CONSTANT A quantity that does not vary. They do not A quantity that does not vary. They do not require statistical study.

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

SAMPLE It is a part of a population It is a part of a population It is a group of sampling units that form part of a population It is a group of sampling units that form part of a population It is a subset of population It is a subset of population

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

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

DATA consist of discrete observation of an attribute or event that carries little meaning when considered alone. consist of discrete observation of an attribute or event that carries little meaning when considered alone. Data is transformed into information by reducing them, summarizing them & adjusting them for variation. Data is transformed into information by reducing them, summarizing them & adjusting them for variation. Data are analyzed to assess changes in diseases and health situations in a community. Data are analyzed to assess changes in diseases and health situations in a community.

Qualitative Data: There is no notion of magnitude or size of a characteristic or attribute as the same can’t be measured. There is no notion of magnitude or size of a characteristic or attribute as 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 females Males or females VARIABLE IS DISCRETE VARIABLE IS DISCRETE

QUANTITATIVE DATA It has a magnitude It has a magnitude there are two variables, characteristics and frequency. there are two variables, characteristics and frequency. The variable is CONTINUOUS The variable is CONTINUOUS

Classification of data Become concise Become concise Arouse interest of reader Arouse interest of reader Become simple and meaningful Become simple and meaningful needs few words to explain needs few words to explain Define a problem & suggest solution Define a problem & suggest solution Helpful for further analysis Helpful for further analysis