Random Sampling of Hong Kong telephone numbers
Fixed line
After successful contact with the household, if there were more than one member at home eligible for an interview, we would employ the “Next Birthday Rule” method to select the eligible member whose birthday comes soonest.
Mobile phone
After successful contact with the phone user, the eligible respondents will be invited for interview.
*Prior to 2019, the survey was conducted through fixed line phones only. Since 2019, it was transitioned to a mixed mode of fixed line and mobile phones.