Seminar Survey methods in

community medicine

• Presented by

Dr.S.D.Shekde

JR 2

• Guided by

DR. V. M.HOLAMBE

H.O.D.

Assist. Professor

Dept Of Comm. MedicineG.M.C. LATUR

Date-17/11/14

survey methods in

community medicine

contents

• 1.introduction and terminology .• 2. definitions of terms .• 3. objectives and uses of survey .• 4. types of survey .• 5. heath survey & its methods .• 6. pre-requisites for survey .• 7. types of information available from survey .• 8. Types of epidemiological study .• 9.stages of investigation .• 10. planning phase .• 11. qualities of a good research• 12 .summary .• 13.references

Introduction.

Survey :• A method of gathering information from a sample of

individuals.

• A powerful, scientific tool for gathering accurate and

useful information.

• Gathering information, asking questions from a

sample of population. It may be;

– Verbal surveys are often known as interviews,

and;

– Written surveys are questionnaires.

Introduction and Terminology

• Surveys constitute the basic tool of research in communities.

• Surveys mainly concerned with groups or populations rather than individuals.

• Outcome of surveys represents the sum total of the group and cannot reflect each individual’s concern or interest.

• survey methodology studies the sampling of individual units from a population and the associated survey data collection techniques, such as questionnaire construction and methods for improving the number and accuracy of responses to surveys.

• Polls about public opinion, public health surveys, market research surveys, government surveys and censuses are all examples of quantitative research that use to answer questions about a population.

• Although censuses do not include a "sample", they do include other aspects of survey methodology, like questionnaires, interviewers, and non response follow-up techniques.

• Surveys provide important information for all kinds of public information and research fields, e.g., marketing research, psychology, health professionalsand sociology.

Definitions of terms

• Survey : survey is defined as non-experimental observations in population or its sample.

• A survey (or observational study) is an investigation in which information is systematically collected, but the experimental method is not used-that is no active intervention by the investigators.

• In our field observation relate to health, health related events or disease.

• Surveillance --: it is defined as continuous scrutiny of all aspect of occurrence and spread of disease that are pertinent to effective control .

• surveillance means maintenance of on going watch over the status of a group or communities.

• Surveillance is therefore , continuous activity whereas a survey is done for specific purpose at specific time only.

• Monitoring -: is defined as the performance of and analysis of routine measurements for detecting changes in the environment and heath status in population.

• monitoring is on going watch over activities of health services.

• demographic surveillance means on going measurement of the size of population.

• exploratory study is a descriptive survey designed to increase the investigators familiarity with the problem he wishes to study. it is some times called pilot study.

• methodological study is performed for collecting information on the feasibility or accuracy of research method.

• a morbidity survey is study of occurrence and distribution of disease in population.

• house hold survey refers to survey of illness and disability performed by interviewing persons in their homes.

• KAP study of knowledge attitudes and practices.

• out break investigations aim at determining causes of out break in order to control it.

• health practice research is concerned with organizational problems.

Objectives of survey

• 1) planning and evaluating health programme .

• 2) to gather accurate, reliable and standardized information about disease/heath problem.

• 3)to gather information about the effectivity and efficiency of health programme .

• 4)to obtain new information about disease/ health problem.

USES OF SURVEY

To assess the magnitude of a specific disease condition or health related events in specified community or well-defined geographical area.

To guide planning of national, regional or local health programs.

To evaluate control activities or national health programs.

To study community perceptions and attitude related to health and disease.

To evaluate degree of utilisation of health care facilities.

To provide data for planning and evaluation of community intervention and health educational activity.

To suggest and test hypotheses on health related events and diseases condition.

Surveys are useful for research,training,planning and evaluation.

Classification of Surveys

Three broad Classifications

• By size (social, community and school

surveys).

It is about the segment of the society at which

we are focusing upon/ depending upon the

nature of the research and the focus of the

conclusion

• By result type (quantitative or qualitative). 18

Types of Survey

Descriptive surveys are used to gather information largely on what people do and think. Thus a researcher might use this type of survey to find out what young people think about drugs, what drugs they might use, and with what frequency.

Analytic surveys are used to answer research questions or to test hypotheses. A researcher might collect data from the general population which detailed information on health habits, e.g. Diet, exercise, smoking and so on. This information might then be used to make predictions concerning the state of health of the population at some future date.

19

Types of Surveys

(Time and Population)

A. Cross-sectional surveys. Collect

information from the sample at the same point time.

B. Longitudinal surveys. Information is collected

at different points in time in order to study changes

over time .

20

Types of survey

• Surveys are named according to its main objective ( viz: nutritional survey, diet , social survey etc..) but depending on methods adopted, there are four basic types of survey.

• 1) Mass survey .

• 2) Sample survey .

• 3) Pilot survey .

• 4) At risk survey .

• Mass survey: When information is collected from the entire population it is called as mass survey .

• Mass survey are not to be repeated very frequently .

• Census conducted every ten years in our country is an example of mass survey .

• Sample survey: when the information is obtained, not from the entire population ,but from its sample ,it is called sample survey .

• If proper sampling procedure is adopted and if the sample size is adequate ,then sample surveys can give reliable and quick estimates about population .

• Sample survey are cheaper and faster than mass survey .

• For example- annual surveys conducted for births and deaths under sample registration scheme are sample survey.

• Pilot survey: when survey is to be conducted on large scale and when it involves complicated design ,questionnaire and information ,a survey on smaller scale is usually done prior to main survey , this is called pilot survey .

• It is helpful for pre testing the questionnaire, training the people and assessing the feasibility of certain procedures to be conducted in the main survey .

• At risk survey: when the information is collected from individuals/or population that are at a higher risk of the problem at hand than the general population the survey is called at risk survey .

• Such survey need the knowledge about who is “at risk” .

• These surveys give more information about the section of the population “at risk” for the given problem .

Health survey

• "health surveys" is used for surveys relating to

any aspect of health - morbidity, mortality, nutritional status, etc.

• When the main variable to be studied is disease suffered by the people, the survey is referred to as "morbidity survey".

• Health surveys may be cross sectional or longitudinal; descriptive or analytic or both

Surveys in the health

sector

Health survey

Studying a population or a particular segment of population in order to asses

its health problems or to detect condition to which preventive measures

may be applied.

Morbidity survey

It is a specific survey dealing with only one element in the full range of possible components of a health survey

Utilization survey

It demonstrate how many people are utilising services provided by specific facilities.

Health survey methods

• Broadly, the following types of surveys would be covered under health survey

a) surveys for evaluating the health status of a

population, that is community diagnosis of

problems of health and disease.

It is information about the distribution of these problems over time and space that provides the fundamental basis for planning and developing needed services .

• B) surveys for investigation of factors affecting health and disease, e.g, environment, occupation, income, circumstances associated with the onset of illness, etc.

• C) surveys relating to administration of health

services, e.g., use of health services, expenditure

on health, evaluation of population health needs

and unmet needs. evaluation of medical care, etc.

Methods of health survey

• The method employed for data collection, health surveys can be broadly classified into 4 types

• a. Health interview (face-to-face) survey .

• b. Health examination survey .

• c. Health records survey .

• d. Mailed questionnaire survey .

• The health interview (face-to-face) survey is an

invaluable method of measuring subjective phenomena such as perceived morbidity, disability and impairment; economic loss due to illness, expenditure incurred on medical care;

Opinions, beliefs and attitudes; and some behavioural characteristics.

It has also the advantage of giving population based data.

• Health examination surveys generally provide more valid information than health interview surveys.

• The survey is carried out by teams consisting of doctors, technicians and interviewers.

• The main disadvantage of a health examination is that it is expensive and cannot be carried out on an extensive scale.

• The method also requires consideration of providing treatment to people found suffering from certain

diseases .

• Health records survey involves collection of data from health service records.

• This is obviously the cheapest method of collecting data.

• This method has several disadvantages :

• a) the estimates obtained from the records are not population-based .

• b) lack of uniform procedures and standardization in the recording of data.

• Mailed questionnaire survey . An alternative

method of measuring subjective phenomena is the self-administered Questionnaire, i.e., a questionnaire without an interviewer.

• The use of questionnaires is simpler and cheaper, and they may be sent,

• For example- by mail to persons sampled from a given target population .

Pre requisites for survey

• 1) Resources

• 2)Co-operation from population .

• 3)training of the personnel .

• 4)Pre-testing

• 5) Mock –survey

• 6) Administrative planning .

• 1. RESOURCES: resources include personnel, finances and materials (man/money/ materials) .

• Before undertaking the survey adequacy of resources must be ensured .

• 2. Co-operation from the population:

• Survey involve obtaining variety of information from variety of persons . So necessary to obtain their co-operation .

• This can be ensured only if the respondents understand the objectives and utility of survey

• Involvement of influential persons in a community ( viz- elected representatives, social worker, lions/rotary club etc..) would facilitate the efforts in obtaining co-operation .

• 3.Training of the personnel: surveys have very specific objectives and the information to be collected may be of a specialized nature .

• Training of the persons for all aspects is required and contents of training are :

• A) explanation of the objectives of the survey .

• B)explanation of the questionnaire/interview schedule

• C)training in the use of new equipment.

• D)detailed programme of the survey .

• E)participation in mock survey/pilot survey.

• 4) Pre-testing : to test the questionnaire on small number of individuals before the survey. This is called pre- testing .

• Pre-testing is also used for training the personnel.

• 5) Mock survey: this is the trail of the survey on small scale .

• It give an opportunity for prior use of questionnaire, equipments, and investigations

• 6) Administrative planning : it includes recruitment of personnel, procurement of equipments , printing the questionnaire, making the transport arrangement, fixing the time schedule, etc ..

Types of information available from survey

• 1) Demographic :

• Information about size ,composition and distribution of the population can be obtained through survey

• This provides denominator for calculation of various rates ,ratios and proportions

• 2) Vital events : -

• The data about vital events (births, deaths, marriage & divorce ) is available through surveys, which is likely to be more accurate ,reliable & standardized .

• 3) Morbidity :-

• Information about the specific aspects of morbidity like incidence , duration & severity can be obtained from survey .

• 4) Related factors :-

information about factors related to the problems viz. nutritional status ,educational status , occupation, economic, environmental conditions etc can be obtained from survey.

• Requirements of Objectives of descriptive,analaytical,and evaluative studies.

• 1. they must meet the purpose of study

• 2. they should be formulated clearly.

• 3. the should be expressed in measurable terms.

Types of Epidemiological Study

• 1. Descriptive surveys

• cross sectional

• longitudinal ( studies of change)

• 2. analytic surveys

• group based (ecological, trend studies)

• individual based (cross sectional, Cohort, case control)

• 3. Experiments and Quasi experiments (intervention studies, trials)

• Group based

• Individual based

Descriptive Surveys

• may be cross sectional (how many blind people are there in the population)

• may be longitudinal (what is the course of events after infection with HIV virus)

Analytic Surveys

• 1. Group based Analytic Surveys

• comparison of groups or populations

• study of group of groups not group of individuals (group of countries compared with respective to their death rates from cirrhosis of liver).

• group based studies may some times yield misleading results due to inaccuracy or unavailability of data.

• 2. Individual based analytic surveys

• study of groups but utilize information about each individual in group.

• In simplest form it is used to test hypothesis that a specific factor is determinant of specific disease.

• cross sectional study examine association existing in a group at a given time.

• cohort study is analytic follow-up in which people exposed and non exposed followed.

• case control study examine relation between suspected casual factor and a disease.

• if case control study is perform in the frame word of cohort study so that experiences of new cases identified in the study.

• cohort can be compared with that of control of same cohort it called nested case control study.

• A quasi-experiment is an empirical study used to estimate the causal impact of an intervention on its target population.

• most common form of a quasi-experimental study includes a pre-post test design with both a treatment group and a control group,

• quasi-experimental studies are often an impact evaluation that assigns members to the treatment group and control group by a method other than random assignment.

Stages of an Investigation/steps in survey

• 1. Preliminary stage

• a. clarifying the purpose

• b. previewing the literature

• c. ethical consideration

• d. formulating the topic.

• 2. Planning

• 3. Preparation for data collection

• 4. Collection of data.

• 5. Processing of data.

• 6. Interpreting the result

• 7. Reporting the finding

The planning phase• 1.formulation of study objectives:

• 2.planning of methods

a . the study population (whom?):

Selection and definition

Sampling

Size

B . variables (what to measure?)

Selection

Definition

Scales of measurements.

C. Methods of collecting data

D. Methods of recording and processing:

First Steps

• clarifying the purpose

• use of the literature.

• ethical considerations.

• formulating the topic.

clarifying the purpose

• clarify whether the study is pure or applied.

• is the purpose of obtaining information will form the basis for utilization of resources.

• is it to identify persons at special risks of a specific disease.

• is it to add knowledge on specific aspect of aetiology.

• is it to stimulate public interest, for welfare of population, , for application of health programme?

• reason of study should be clear to investigator.

• it is necessary to describe the purpose in some detail to justify the proposed study.

• review previous work on subject, present state of knowledge, significance of proposed study that is case for action.

• honest self examination is desirable to clarify the purpose and bias.

Use of Literature

• published experiences are useful for indicating the presence and nature of research problem.

• useful for planning and interpretations of findings.

• investigator should be acquainted with important study Literature before study .

• references should be filed in organized way manually or computer data base.

• it is of limited use to wait until reports of study are written.

• long list of references without proper use is unnecessary.

• assess the accuracy of findings . judge if inferences are valid decide whether the study has relevance to your needs.

Ethical considerations

• Before planning the study satisfy yourself that it is ethical to do the study and can be done in ethical way.

• is it ethical to permit the study at the expense of activities directly promoting community health.

• scientifically unsound studies are unethical.

Formulating the topic

• Done after the purpose and moral justification of study are clear.

• it can be done in general terms and many times it is simple to formulate.

• at early stage formulation of topic is regarded as provisional as difficulties may arise in future.

2.PLANNING STAGE

1. State the objectives of the survey

We have to define specifically the problem we intend to solve.

If we cannot state the objectives of the survey we are unlikely to generate useable results.

We have to be able to formulate something quite detailed, perhaps organized around a clear statement of a testable hypothesis.

Clarifying the aims of the survey is critical to its ultimate success.

64

2. Define the study population

• The study population is group that studied, either in toto or by selecting a sample consisting of individual members of the group for investigation.

• If sample is chosen, the study population from which it is selected may be also be called the sampled population or the parent population.

• Appropriateness & practicability should be taken into account durning selecting the study population .

• If a study population is believed to be typical of a broader population to which the findings may be generalized, the latter population may be termed the reference population or external population.

Sampling

• Sample – a finite subset of statistical individuals in a population .

• Sample size- the number of individuals in a sample .

• Sampling is most frequently used in survey.

• The sample must be well chosen ,so as to be representative of parent population.

SAMPLING

• The process of selecting a sufficient number of elements from the population, so that results from analyzing the sample are generalizable to the population .

Define the population

Determine the sample

frame

Determine the sampling design

Determine the appropriate sample size

Execute the sampling process

THE SAMPLING PROCESS

CHARACTERISTICS OF A GOOD SAMPLE DESIGN

• (a) Sample design must result in a truly representative sample.

• (b) Sample design must be such which results in a small sampling error.

• (c) Sample design must be viable in the context of funds available for the research study.

• (d) Sample design must be such so that systematic bias can be controlled in a better way.

• (e) Sample should be such that the results of the sample study can be applied, in general, for the universe with a reasonable level of confidence.

Types of sampling methods

Quota sampling

• Quota sampling: In stratified sampling the cost of taking random samples from individual strata is often so expensive that interviewers are simply given quota to be filled from different strata, the actual selection of items for sample being left to the interviewer’s judgement . This is called quota sampling.

• The size of the quota for each stratum is generally proportionate to the size of that stratum in the population.

• Quota sampling is thus an important form of non-probability sampling.

• Quota samples generally happen to be judgementsamples rather than random samples.

The Quota Sample

Determine what the population looks like in terms of specific qualities.

Create “quotas” based on those qualities.

Select people for each quota.

The Snowball Sampling

Find a few people that are relevant to your topic.

Ask them to refer you to more of them.

• Theoretical Sampling

• Definition

• The process of selecting "incidents, slices of life, time periods, or people on the basis of their potential manifestation or representation of important theoretical constructs"

• Theoretical sampling is an important component in the development of grounded theories.

. 3. Method of collecting and processing data

In our discussion we will mainly focus on data collection instruments.

METHODS OF DATA COLLECTION

Data collection instruments:

1.Observation

2.Questionnaires and schedules

3.Interview

Supplementary diagnostic instruments

:

such as hemoglobinometer, infantometer, microscope, ECG

and X-ray machines, etc.

Types of Observation :

• Participant vs Non-participant observation

• Structured vs. Unstructured observation

• Non Participant Observation:

• Someone who attempts to observe people without interacting with them .

• Without their knowledge that they are being observed .

• Participant Observation:

• Observer participates actively, for an extended period of time

• May require observer to live or work in that area .

• Assumes that observer will become accepted member of the group or community .

• Historically field research has been associated most strongly with participant observation.

• Unstructured Observation :

• Early phase of the research .

• How to do unstructured observation

• Take a notebook and pen

• Note down when you see something interesting.

• Write down theories as you form them.

• Don’t jump to conclusions straight away.

• Look for more evidence.

• Structured Observation :

• Greater control of sampling .

• Measurement of error .

• This is more like a survey, where every respondent is asked the same set of questions. But in this case, questions are not asked. Instead, particular types of behavior are looked for and counted.

• Advantages:

Do not depend on recall of memory

A good deal of information we can gather.

• Disadvantages:

Cultural barrier

An individual’s belief and perception cannot be adequately represented.

May consume a lot of time.

Not everything is amenable to observation. e.g.,sexual behaviour cannot be observed.

INTERVIEWS :

• This is a very popular method of data collection.

• This involves juxtaposition of the interviewer and the interviewee.

• If the interviewee doesn’t understand a question , it can be explained to him and if more details are desired , additional queries can be posed.

• INTERVIEWING IS AN ART.“ WHAT TO BE ASKED AND HOW TO PROCEED” are

crucial to the success of this method.

Types of Interview:

There are two types of interviewing formats :

• (a) Structured interview :

The format and order of investigation is set out right at the beginning.

• (b) Unstructured : This consists of only an open ended questionnaire with everything else left to the discretion of the interviewer, e.g. a journalist’s interview.

• Advantages of interviews :

• It has flexibility which is not offered by questionnaire .

• Better coverage is obtained.

• Validitiy of the collected information can be tested.

• Interviewer can motivate the poorly motivated responders .

QUESTIONNAIRES

• An effective questionnaire will follow these rules:– As brief as possible.

– Focus on information, not otherwise accessible to the investigator.

– Aimed at obtaining factual data, rather than opinions, impressions, or estimates.

– The wording of every item ought to be understandable and familiar .

– For the same reason, the items should be

arranged in a neat and logical order.

– The questionnaire should be conveniently

planned and set up to take a minimum of the

respondent’s time.

– Clear instructions must be included as to the way

the answers are to be indicated.

QUESTIONNAIRES

• Requirements of questions :

• 1. must have (at least) face validity .

• 2. respondents can be expected to know the answer .

• 3.must be clear and unambiguous .

• 4. must be fair .

• 5. must be user friendly .

• Advantages of questionnaire :

• A) it is less expensive than interview .

• B) it can be ensure uniformity especially for impersonal data( age, sex, etc..) .

• C) information can be given at leisure without pressure of time on respondent .

Kind of Question Structure.

Which kind of question structure to use?

• Open-ended.

• Close-ended with ordered choices.

• Close-ended with out unordered choices .

• For example

• Questions may be open-ended ("Why do you feel that way?") or closed ("Do you approve or disapprove?").

Investigations/Measurements

• Some investigations may be done to obtain information about specific aspects .

• For example-

a) weighing food cooked daily in a diet survey

b) anthropometric measurements in nutritional survey .

Compilation & Data Analysis in Survey

• Compilation is the systematic arrangement and presentation of the data .for this data is arranged in various groups viz - chronological groups, groups as per specific characteristics like age, sex, occupation, etc…

• The compilation and analysis must be relevant to the predecided objectives .

• Dummy tables are prepared for this before the compilation is made and data is compiled accordingly. .

Compilation & Data Analysis in Survey

• Analysis work after tabulation is generally based on the computation of various percentages, coefficients, etc., by applying various well defined statistical formulae.

• In brief, the researcher can analyse the collected data with the help of various statistical measures.

. Data analysis

• Clean the questionnaires.

• Code the questionnaires.

– Close-ended questions.

– Open-ended questions.

– Partially close-ended questions.

– Missing data.

• Decide which statistics are most useful to you.

• Interpretation. Look for results that matter.

Results/ Reporting of survey

• The report may also be presented with the help of tables and graphs .

• This consists of informing the appropriate authorities ,the observation made in the survey . This contain objectives, materials and methods used, and observation in the survey.

• A good report also indicates the extent to which the objectives of survey are fulfilled .

Results/ Reporting of survey

• Abstract or executive summary of the survey

• Problem statement.

• Methods and procedures undertaken.

• Error structure and the acceptability thereof.

• Findings.

• Implications.

• Appendices.

• The layout of the report should be as follows:

• (i) the preliminary pages;

(ii) the main text,

(iii) the end matter.

• In its preliminary pages the report should carry title and date followed by acknowledgements and foreword.

• Then there should be a table of contents followed by a list of tables and list of graphs and charts .

• The main text of the report should have the following parts:

(a) Introduction:

(b) Summary of findings:

(c) Main report:

(d) Conclusion:

• At the end of the report, appendices should be enlisted in respect of all technical data. Bibliography, i.e., list of books, journals, reports, etc.,

Qualities of a good research

• 1. Good research is systematic:

• 2. Good research is logical:

• 3. Good research is empirical:

• 4. Good research is replicable:

SUMMARY

• survey is a scientific and systematic search for pertinent information on a specific topic. In fact, research is an art of scientific investigation

• It is a careful investigation or inquiry specially through search for new facts in any branch of knowledge .

• Survey/research comprises defining and redefining problems, formulating hypothesis or suggested solutions; collecting, organising and evaluating data; making deductions and reaching conclusions; and at last carefully testing the conclusions to determine whether they fit the formulating hypothesis.

• Surveys are useful for

• Research,

• Training,

• Planning

• Evaluation.

REFERENCES• Textbook of survey methods in community medicine ,by J.H.ABRAMSON

, Z.H. ABRAMSON . Fifth edition .

• Textbook of community medicine by Dr .J .P. Baride , Dr. A. P. Kulkarni . Third edition .

• K Park Textbook of Preventive and Social Medicine; Banarasidas BhanotPublication;22th edition .

• Text Book of Public Health and Community Medicine, Published by Department of Community Medicine, Armed Forces Medical College, Pune .

• Principles and practice of biostatistics , by DR J. V. DIXIT . Fifth edition .

• Textbook of research methodology ( methods and techniques) second revised edition by C.R. KOTHARI

• Frankel, J. And Wallen, N.. How to design and valuate research in education. McGrawHill (2000).

Hill way , T. Introduction to research. H.M.Co. (1964).

• Brochure, what is a survey?, Bill Kalsbeek, 1995 publications officer, ASA section on survey research methods