2P11- Lecture 5
The survey is a flexible research approach used to investigate a wide range of topics
All questionnaires should take into account:
· whether the questionnaire will be self-completed
· the literacy level of the respondents
· the expected response rate
· the resources available
· topic and population of interest
Advantages of using a survey
· surveys have internal and external validity
· surveys are efficient
· surveys can cover geographically spread samples
· surveys may have ethical advantages
· surveys are flexible
Limitations of the survey approach
· surveys are dependent upon the chosen sampling frame
· surveys are not so good at explaining why people think or act as they do
· interview surveys are only as good as the interviewers asking the questions
Methods of collecting survey data
i. face-to-face interviews
· the ability to carry out a longer interview on a more complex topic
· a higher response/completion rate
· the ability to use visual aids and prompts
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· the opportunity to develop a rapport
· can reach some people that due to disability or socio/economic status may not normally be
· labour intensive for large samples
· time consuming
· difficult to contact people at home
· difficult to get honest answers to personal/sensitive questions such as drug-taking, diet, etc
ii. telephone interviews
· can build rapport
· easier to contact geographically-spread respondents
· may be easier to contact professionals
· can be cheaper and quicker than a face-to-face survey
· high completion rate if person commits to questionnaire
· not appropriate if sampling frame do not all have equal access to a telephone
· sampling frame - even those with a telephone may be ex-directory
· cannot use visual aids
· interview may be impersonal
· interview length is limited
iii. postal questionnaires
· not labour intensive, possible to mail a large sample, and therefore may be cheaper than
face-to-face or telephone
· gives people the opportunity to answer questions in their own time; they may need to refer
to documents etc.
· useful for a widely distributed sample
· possibly lower response depending on topic and motivation
· usually takes much longer, need to give people sufficient time to reply and send out
· not suitable for people with literacy problems
· cannot guarantee that the person who completed it was the target participant
Response rates for postal questonnaires
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Items to include in a Questionnaire
A closed question is one where the possible answers are defined in advance and so the
respondent is limited to one of the pre-coded responses given
An open-ended question does not constrain possible responses.
An example of an open-ended question with partial pre-coding:
“What do you think is the cause of your asthma?”
DO NOT READ OUT (INTERVIEWER INSTRUCTIONS) CIRCLE ALL THAT
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Air pollution 1
Traffic pollution 2
Dust / dust mites 4
Pets / dog / cat 5
Work / occupation 7
Certain foods / dairy products 8
Inherited from parents 9
Other, write in _________________________
„How long ago is it since you last saw a dentist?‟
Within the last month 
More than a month ago but within the last 6 months 
More than 6 months ago but within the last year 
More than a year ago 
Male „1‟ or „M‟
Female „2‟ or „F‟
1. Do you consider yourself to be obese?
2. Are you fat?
3. Do you consider yourself to be overweight?
4. Do you have a regular, balanced diet?
5. Do you ever take drugs to control your weight?
6. Has your GP ever prescribed medicine to control your weight?
7. What was the name of the drug prescribed, its dosage and how many times a day?
8. How many times a year do you start a diet?
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9. What is your weight and height?
As a rule, it is best to move from the general to the particular when designing a
1. Is stress affecting your personal life?
2. In which department do you work?
3. Which is the best way of coping with stress?
4. How many home visits a week do you have?
Filters and instructions
3. Are you housebound?
Yes ___ 1 (If Yes, go to Q4)
No ___ 2 (If No, go to Q5)
4. What type of home help do you receive?
Which statement best describes your