6,000 Chinese talk about sex

ESWN translates an interesting background story about the methods used by professor Pan Suiming if the Renmin university in Beijing, who organized a sex-survey among 6,000 Chinese nation-wide. More than about the subject itself, the article explains how the surveys were being done.
Internet users had been very critical about some of the conclusions, but the survey looks very well done, getting a very high response rate for this kind of sensitive subjects.

The first "secret of success" was that the interview must not take place at home. Presently, most survey research in China consisted of knocking on the door and filling out the questionnaire right there and then. Sex surveys cannot be done this way.
"If I ask you in front of your family members whether you have a sex partner, would you tell me?" The confidentiality of this survey is paramount.