[Medical research using Internet questionnaire in Japan].

As the method for questionnaire studies, mail survey and interview survey are frequently used. The utility and validity of applying the Internet method to medical studies have yet to be fully evaluated. For the present investigation, we reviewed 36 Japanese original articles using Internet questionnaire reported through to April 2005. Although original papers using the Internet method have been increasing in recent years, they are still limited in number. There is comparatively much research on disease with many patients in youth and early manhood, such as allergic ailments (allergic rhinitis, atopic dermatitis, and hives). As compared with conventional methods, the advantages of the Internet approach are convenience for both investigators and respondents and the ability to quickly collect data. The disadvantage is that the user's age range is more concentrated. Since samples are extracted from individuals who are registered as monitors, a greater sampling error may occur as compared with a random sampling method. However, it is to be expected that continued explosive growth of the Internet would decrease the limitation in user's age. If more elderly people participate in questionnaire studies using the web, research into more illnesses should be facilitated. Considering the inherent advantage, it is thought that Internet method can become the leading tool for sociomedical and clinical research in the near future.