In the method of questionnaire by post, a questionnaire is dispatched to respondents by post. The respondents fill up the questionnaire and send it back.

The advantages and disadvantages of this method are as follows:

Advantages:

• This method is simple, quick and provides large amount of information with less cost.
• This method proves to be more efficient if the information is to be collected from educated and responsible respondents.
• An investigator can get information from the respondents of those areas where it might be difficult to reach personally or by telephone.

Disadvantages:

• This method is not quite useful if the respondents are illiterate and are lacking the sense of cooperation.
• Sometimes respondents do not bother to read or return the questionnaire.
• It is not possible to check whether the information given is correct or incorrect.
• Sometimes, because of fear of information being misused, even educated respondents with sense of understanding avoid to provide written information or ignore returning back the questionnaire.
• Because of laziness and gloom of the respondents, there may be a loss of questionnaire or delay in getting the information.
• There is lack of assistance. Therefore clarification of the instructions or giving explanation of the questions that may arise is not attended. As a result it is possible that respondent may not provide the correct information.