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Survey MethodologySurvey Design

EPID 626

Lecture 5

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Lecture Overview

• Discussion about survey study design issues

• Hands-on exercise with WIN data

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Methods of data collection

• Mail survey

• Telephone survey

• Personal interview

• Computer-assisted interview

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Considerations

• Available information

• Survey population skills and motivation

• Desired data

• Response rates

• Resources (money and time)

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Mail survey• Available information?

– Need complete and accurate addresses

• Survey population skills and motivation?– Reading, writing, language skills– Knowledge of topic– Interest in subject– Limited opportunity to convince someone

to participate

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Mail survey (2)

• Desired data?– No interviewer involved to clarify, prompt or

establish rapport– Respondents have more time to consider

responses– Can access hard-to-reach samples– Difficult to designate a respondent

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Mail survey (3)

• Response rates– May be very low– May increase with telephone follow-up

• Resources– Relatively low cost– Requires minimal staff and facilities

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Telephone survey

• Available information? – Need a good list of telephone numbers if

you’re not using RDD

• Survey population skills and motivation?– Skills needed are minimal– Language?– Limited opportunity to convince someone

to participate

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Telephone survey (2)• Desired data?

– May be less appropriate for sensitive or personal information

– Can’t use visual aids– May miss those without phones, who screen

calls, who aren’t home etc.– Have advantages of interviewer

administration such as ability to clarify and probe

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Telephone survey (3)

• Response rates?– Better than mail surveys– Usually not as good as personal interview– RDD especially is low

• Resources?– Requires less than does personal interview– May take less time than mail or personal

interview surveys

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Personal Interview Survey• Available information?

– May need an address – May not (area probability sampling)

• Survey population skills and motivation?– Skills needed are minimal– Have an opportunity to convince people to

participate, establish rapport– Language?

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Personal Interview Survey (2)• Desired data?

– Interviewer can explain, clarify, and probe– Can use visual aids– Rapport may encourage sharing of

sensitive information– Can get more information with a longer

survey– May be able to ask more open-ended

questions

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Personal Interview Survey (3)

• Response rates?– Usually considered very good

• Resources– Usually very expensive– Need a well-trained staff – Need supervision– May take a long time

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Computer assisted survey• More of a tool than a design really

– Can be used as a stand-alone self-administered survey

– Can be used in conjunction with telephone or personal interviews

– Can use in conjunction with video to simulate a personal interview

• If desired, you can match some characteristics, such as age, race, and gender of the interviewer with the subject (more on this later)

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Computer assisted survey (2)

• Available information?– Depends on other elements of the study

design

• Survey population skills and motivation?– People who are not familiar with computers

may feel uncomfortable– Can adjust the language– Can read questions aloud

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Computer assisted survey (3)

• Desired data? – Can follow complex question patterns or

questions tailored to previous answers– Can identify inconsistencies or missing

data before the interview is over– Can be useful in combination with

telephone survey

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Computer assisted survey (3)

• Response rates? – Depends on other elements of the study

design

• Resources?– No data entry required– If it is self-administered, no interviewer

required