The main purpose of this article is to provide a diverse range of positive evidence that refutes groundless arguments against mail surveys. A versatile set of methodological studies are employed to clarify key factors: return rate, length of time required to conduct surveys, cost requirements, answers by proxy respondents, and ability to obtain straightforward answers. Consequently, the author shows that mail surveys are recognized by most respondents as a survey method that is easy to respond to, simple to participate in, and convenient for filling out and submitting a questionnaire. Furthermore, this work introduces several successful cases of converting methodology from personal interviews or drop-off/pick-up surveys to mail surveys, as well as using these methods together. In particular, the author emphasizes the need for further discussion to clarify the definitions of technical terms, to concretely describe the survey processes used for research papers, and to eventually standardize the quality of survey results so that systematic reviews can be conducted sometime in the very near future.
