Written or self-completed questionnaires are a form of social survey and can be distributed in a range of ways - via post, email or handed out in person
Typically a list of pre-set questions that are closed-end questions with pre-coded answers
Advantages
Practical
Quantifiable data
Representative
Reliable
Limited ethical issues
Practical
Cheap and Quick
Representative
reach a geographically widespread research sample
Reliable
Can be easily repeated due to how the questions are pre set
limited ethical issues
the respondent is under no obligation to answer the questions
Disadvantages
Response Rate
Low Validity
Unrepresentative
The interviewer isn’t there to ask follow up questions and explain questions to the participants if they dont understand
Response rate
Postal questionnaires, obtain a very lowresponserate, which may hinder the representavity
Lowvalidity
People may be more willing to lie
Unrepresentative
You are likely to get a certain group of people e.g. the unemployed or elderly that answer the questionnaires as many other people might be too busy and so you wont get a particularly representative sample
