26/12/2009Dr Salwa Tayel1. 26/12/2009Dr Salwa Tayel2 Associate Professor Family and Community...

26/12/2009 Dr Salwa Tayel 1


Associate Professor Associate Professor

Family and Community Medicine DepartmentFamily and Community Medicine Department

King Saud UniversityKing Saud University

Overview of data-collection techniques


Learning objectives

• To describe various data-collection To describe various data-collection techniques. techniques.

• To differentiate between data-collection To differentiate between data-collection techniques and data collection tools.techniques and data collection tools.

• To identify sources of bias in information To identify sources of bias in information collection an how to control it.collection an how to control it.

26/12/200926/12/2009 Dr Salwa TayelDr Salwa Tayel 44

Data-collection techniquesData-collection techniques allow us to systematically allow us to systematically

collect information about our objects of study (people, collect information about our objects of study (people,

objects, and phenomena) and about the settings in objects, and phenomena) and about the settings in

which they occur. which they occur.

• In the collection of data we have to be systematic. In the collection of data we have to be systematic.

• If data are collected haphazardly, it will be difficult to If data are collected haphazardly, it will be difficult to

answer our research questions in a conclusive way. answer our research questions in a conclusive way.


Data-collection techniques include: Data-collection techniques include:

• Using available information.

• Observing

• Interviewing (face-to-face).

• Administering written questionnaires,

• Focus group discussions (FGD) and

• Other data-collection techniques.


a. Using available informationa. Using available information

• Usually there is a large body of data already

collected by others, although it may not necessarily

have been analyzed or published.

• Locating sources and retrieving the information is a

good starting point in any data collection effort.


For example

• Analysis of the information routinely collected by

health facilities can be very useful for:

– identifying problems in certain interventions

– flows of drug supply,

– identifying increases in the incidence of certain diseases.

• Sometimes the factors contributing to the problem

may also be identified from the same source;

sometimes additional research will be necessary to

solve the problem.


b. Observingb. Observing

OBSERVATION is a technique that involves

systematically selecting, watching, and recording

behavior and characteristics of living beings,

objects, or phenomena.

• Observation of human behaviour is a much-used

data-collection technique.

• It can be undertaken different ways:


• Participant observation:

The observer takes part in the situation he

or she observes

• No participant observation:

The observer watches the situation, openly

or concealed, but does not participate.


• Observations of human behaviour can form

part of any type of study, but as they are time

consuming they are most often used in small-

scale studies.

• Observations can also be made on objects.

For example, the presence or absence of a

latrine and its state of cleanliness may be

observed.


• If observations are made using a defined scale

they may be called measurements.

Measurements usually require additional tools.

• For example,

• In nutritional surveillance, we measure weight

and height by using weighing scales and a

measuring board.

• We use thermometers for measuring body

temperature.


c. Interviewingc. Interviewing

An INTERVIEW is a data-collection technique that

involves oral questioning of respondents, either

individually or as a group.

• Answers to the questions posed during an interview

can be recorded by writing them down or by tape

recording the responses.

• Interviews can be conducted with varying degrees of

flexibility.


High degree of flexibility: High degree of flexibility: • Interviews using an interview schedule, to ensure

that all issues are discussed,

• but allowing flexibility in timing and the order in which

the questions are asked.

• Questions are open-ended: the respondent is

unrestricted in what and how he answers.

• The interviewer may ask additional questions on the

spot to gain as much useful information as possible.


Uses

• The unstructured or loosely structured method of asking

questions can be used for interviewing individuals as well as

groups of key informants.

• A flexible method of interviewing is useful if a researcher

has as yet little understanding of the problem or situation he

or she is investigating.

• It is frequently applied in exploratory studies and also used

during case studies.


Low degree of flexibility: Low degree of flexibility: Interviews using a questionnaire with a fixed list of

questions in a standard sequence that have mainly

fixed or pre-categorized answers.

Uses:

• when the researcher is relatively knowledgeable about expected answers and

• when the number of respondents being interviewed is relatively large.


d. Administering written questionnairesd. Administering written questionnaires

A WRITTEN QUESTIONNAIRE

(self-administered questionnaire) is a data

collection tool in which written questions

are presented that are to be answered by

the respondent in written form.


A Written questionnaire can be administered by:

• Sending questionnaires by mail with clear

instructions on how to answer the questions and

asking for mailed responses;

• Gathering all or part of the respondents in one place

at one time, giving oral or written instructions, and

letting the respondents fill out the questionnaires; or

• Hand-delivering questionnaires to respondents and

collecting them later.


e. Focus group discussions e. Focus group discussions (FGD)(FGD)

• A focus group discussion allows a group of A focus group discussion allows a group of

8 - 12 informants to freely discuss a 8 - 12 informants to freely discuss a

certain subject with the guidance of a certain subject with the guidance of a

facilitator or reporter. facilitator or reporter.


Differentiation between Differentiation between Data-collection Data-collection techniques and tools. techniques and tools.

Data-collection techniquesData-collection tools

• Using available information Checklist, data-compilation forms

• Observing Eyes and other senses, pen and paper, watch, scales, microscope, etc.

• InterviewingInterview schedule, checklist, questionnaire, tape recorder

• Administering written questionnaires

Questionnaire


Using available Information Using available Information

Advantages:Advantages:

• Inexpensive, because data are already there. Inexpensive, because data are already there.

• Permits examination of past trends.Permits examination of past trends.

Disadvantages:Disadvantages:

• Data are not always easily accessibleData are not always easily accessible

• Ethical issues concerning confidentiality may arise. Ethical issues concerning confidentiality may arise.

• Information may be imprecise or incomplete Information may be imprecise or incomplete


ObservingObserving


• Gives more detailed and context-related Gives more detailed and context-related

informationinformation

• Permits collection of information on facts Permits collection of information on facts

not mentioned in the questionnaire.not mentioned in the questionnaire.

• Permits tests of reliability of responses to Permits tests of reliability of responses to

questionnaires.questionnaires.



• Ethical issues concerning confidentiality or Ethical issues concerning confidentiality or privacy may ariseprivacy may arise

• Observer bias may occur (observer may Observer bias may occur (observer may notice only what interests him or her). notice only what interests him or her).

• The presence of the data collector can The presence of the data collector can influence the situation observed influence the situation observed

• Thorough training of research assistants is Thorough training of research assistants is required. required.


InterviewingInterviewing


• Suitable for use with illiterates

• Permits clarification of questions

• Higher response rate than written questionnaires.


• The presence of the interviewer can influence responses

• Reports of events may be less complete than information gained through observations.


Small-scale Small-scale flexible interview flexible interview


• Permits collection of in-depth information and exploration of spontaneous remarks by respondents.


• The interviewer may inadvertently influence the respondents

• Open-ended data are difficult to analyze


Larger-scale fixed Larger-scale fixed interview interview

AdvantagesAdvantages::

• Easy to analyze Easy to analyze

DisadvantagesDisadvantages::

• Important information may be missed because Important information may be missed because

spontaneous remarks by respondents are spontaneous remarks by respondents are

usually not recorded or explored. usually not recorded or explored.


Administering written questionnaires Administering written questionnaires


• Less expensive.

• Permits anonymity and may result in more honest

responses

• Does not require research assistants.

• Eliminates bias due to phrasing questions differently

with different respondents.


DisaDisadvantages:dvantages:

• Cannot be used with illiterate respondents.

• There is often a low rate of response

• Questions may be misunderstood


Importance of combining different Importance of combining different data-collection techniques data-collection techniques

• A skillful use of a combination of different A skillful use of a combination of different

techniques can maximize the quality of the techniques can maximize the quality of the

data collected and reduce the chance of data collected and reduce the chance of

bias.bias.

• Researchers often use a combination of Researchers often use a combination of

flexible and less flexible research techniques. flexible and less flexible research techniques.


• Flexible techniques, such as loosely structured interviews using Flexible techniques, such as loosely structured interviews using

open-ended questions, focus group discussions, and participant open-ended questions, focus group discussions, and participant

observation are also called QUALITATIVE research techniques. observation are also called QUALITATIVE research techniques.

• They produce qualitative information, which is often recorded in They produce qualitative information, which is often recorded in

narrative form. narrative form.

• QUALITATIVE RESEARCH TECHNIQUES involve the QUALITATIVE RESEARCH TECHNIQUES involve the

identification and exploration of a number of often related identification and exploration of a number of often related

variables that give INSIGHT into the nature and causes of variables that give INSIGHT into the nature and causes of

certain problems and intocertain problems and into the consequences of the problems for the consequences of the problems for

those affected.those affected.


– Structured questionnaires that enable the

researcher to quantify pre- or post-categorized

answers to questions are an example of

QUANTITATIVE research techniques. The

answers to questions can be counted and

expressed numerically.

– QUANTITATIVE RESEARCH TECHNIQUES are

used to QUANTIFY the size, distribution, and

association of certain variables in a study

population.


Both qualitative and quantitative research Both qualitative and quantitative research techniques are often used within a single techniques are often used within a single

study.study.

For example

• It has been observed in country X that children

between 1 and 2½ years, who have already

started to eat independently, have

unsatisfactory food intake once they fall ill.

• A study could be designed to address this

problem, containing the following stages:


• Focus group discussions (FGDs) with 2 to 5 groups

of mothers or in-depth interviews with 10 mothers to

find out

• how they feed children in this age group during

different illnesses and

• how they deal with children who have no appetite

when they are sick (exploratory study);


• A cross-sectional survey, testing the relevant

findings of the exploratory study on a larger scale;

• FGDs with women in the study area to discuss

findings and possible questions arising from the

survey and to develop possible solutions for

problems detected.


• It is also common to collect both qualitative and

quantitative data in a single questionnaire.

• Researchers collecting both types of data have to

take care that they:

• Do not include too many open-ended questions in

large-scale surveys, making data analysis difficult; and

• Do not use inappropriate statistical tests on

quantitative data generated by small-scale studies.


BIAS IN INFORMATION BIAS IN INFORMATION COLLECTION COLLECTION

• BIAS in information collection is a distortion that

results in information not being representative

of the true situation.


Possible sources of bias during data Possible sources of bias during data collection collection

1. Defective Instrument

• Questionnaires with:

– Fixed or closed questions when too little is known;

– Open-ended questions without guidelines on how to ask (or to answer) them;

– Vaguely phrased questions; or

– Questions placed in an illogical order.

• Weighing scales that are not standardized.

• These sources of bias can be prevented by: – carefully planning the data-collection process and by

– pretesting the data-collection tools.


2. Observer bias

– Observer bias can easily occur during observation

of loosely structured group or individual interviews.

– There is a risk that the data collector will see or

hear only things in which he or she is interested or

will miss information that is critical to the research.


To avoid observer bias:

– Observation protocols and guidelines for conducting

loosely structured interviews should be prepared,

and training and practice should be provided to data

collectors in using both these tools.

– It is highly recommended that data collectors work

in pairs when using flexible research techniques

and discuss and interpret the data immediately after

collecting it.


3. Effect of the interview on the informant3. Effect of the interview on the informant

This is a possible factor in all interview situations.

• The informant may mistrust the intention of the interview and

dodge certain questions or give misleading answers.

• Such bias can be reduced by adequately introducing the

purpose of the study to informants, by taking sufficient time for

the interview, and by assuring informants that the data

collected will be confidential.


• Importance of the selection of interviewers:

e.g. In a study discussing the reasons for the low

utilization of local health services, for example,

one should not ask health workers from the

health centres concerned to interview the

population.

Their use as interviewers would certainly influence

the results of the study.


4. Information bias4. Information bias

• Sometimes the information itself has Sometimes the information itself has

weaknesses. weaknesses.

• Medical records may have many blanks or Medical records may have many blanks or

be unreadable. be unreadable.

• For example, in a TB defaulter study the For example, in a TB defaulter study the

percentage of defaulters with an incomplete percentage of defaulters with an incomplete

or missing address should be calculated.or missing address should be calculated.


• Another common information bias is due to gaps in Another common information bias is due to gaps in people’s memory; this is called people’s memory; this is called memorymemory or or recall recall bias.bias.

• A mother may not remember all details of her A mother may not remember all details of her child’s last diarrhoea episode and of the treatment child’s last diarrhoea episode and of the treatment she gave she gave two or three monthstwo or three months afterwards. afterwards.

• For such common diseases it is advisable to limit For such common diseases it is advisable to limit the period of recall, asking, for example, ‘Has your the period of recall, asking, for example, ‘Has your child had diarrhoea over the past child had diarrhoea over the past two weekstwo weeks?’?’

4. Information bias4. Information bias


ETHICAL CONSIDERATIONS ETHICAL CONSIDERATIONS Data-collection techniques are likely to cause physical Data-collection techniques are likely to cause physical

or emotional harm for example, by: or emotional harm for example, by:

• Violating informants' right to privacy by posing Violating informants' right to privacy by posing sensitive questions or by gaining access to records sensitive questions or by gaining access to records that may contain personal data; that may contain personal data;

• Observing the behavior or informants without their Observing the behavior or informants without their being aware; or being aware; or

• Failing to observe or respect certain cultural values, Failing to observe or respect certain cultural values, traditions, or taboos.traditions, or taboos.


Methods for dealing with these ethical issues include :Methods for dealing with these ethical issues include :

• Obtaining informed consent before the study or Obtaining informed consent before the study or

interview begins; interview begins;

• Not exploring sensitive issues before a good Not exploring sensitive issues before a good

relationship has been established with the informant;relationship has been established with the informant;

• Ensuring the confidentiality of the data obtained. Ensuring the confidentiality of the data obtained.

– If sensitive questions are asked, for example about If sensitive questions are asked, for example about

family planning practices, it may be advisable to family planning practices, it may be advisable to

omit names and addresses from the questionnaires. omit names and addresses from the questionnaires.


The EndThe End

Thank YouWebsite http://faculty.ksu.edu.sa/73234/default.aspx

[email protected]

26/12/2009Dr Salwa Tayel1. 26/12/2009Dr Salwa Tayel2 Associate Professor Family and Community...

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