Questionnaires can be mailed out to a sample of the population, enabling the researcher to connect with a wide range of people. The questionnaire is typically sent in a packet that contains a cover sheet, introducing the research being conducting, and a pre-paid return envelope for the responses. While the response rate is typically lower than other forms of questionnaires, this can be improved with reminders and incentives. There are examples of government run, compulsory mail out questionnaires, such as the Australian Census, which collect valuable population data.

The advantages of questionnaires

Practical

Large amounts of information can be collected from a large number of people in a short period of time and in a relatively cost effective way

Can be carried out by the researcher or by any number of people with limited affect to its validity and reliability

The results of the questionnaires can usually be quickly and easily quantified by either a researcher or through the use of a software package

Can be analysed more 'scientifically' and objectively than other forms of research

When data has been quantified, it can be used to compare and contrast other research and may be used to measure change

Positivists believe that quantitative data can be used to create new theories and / or test existing hypotheses

The qualities of a good questionnaire

The design of a questionnaire will depend on whether the researcher wishes to collect exploratory information (i.e. qualitative information for the purposes of better understanding or the generation of hypotheses on a subject) or quantitative information (to test specific hypotheses that