 | | Same as the other telephone interviews conducted by the POP Team, all interviews in this rolling survey were conducted by telephone interviewers under close supervision. The target population was Cantonese-speaking registered voters living on Hong Kong Island aged 18 or above. Telephone numbers were first drawn randomly from the residential telephone directories as "seed numbers", from which another set of numbers was generated using the "plus/minus one/two" method, in order to capture the unlisted numbers. Numbers were then mixed in random order to produce the final telephone sample. When telephone contact was successfully established with a target household, one of the registered voters available was selected using the "next birthday rule", which selected the person who had his/her birthday next from all those present. |
