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Date of survey	:	2-4 February, 2009
Survey method	:	Telephone survey with interviewers
Target population	:	Hong Kong citizens of age 18 or above
Sampling method	:	The contacts were successfully established with a target household, one target respondent was selected. If more than one subject had been available, selection was made using the "next birthday rule" which selected the person who had his/her birthday next from all those present.
Sample size	:	1011 successful cases
Overall Response rate	:	73.7%
Std. sampling error	:	Less than 3.1%

Table 1 Public survey - Calculation of effective response rate

Overall Response rate
= [ Successful cases / (Successful cases + Incomplete cases* + Refusal cases by eligible respondents^) ]
= [ 1,011 / ( 1,011+ 43 + 297 + 7 + 13 ) ]
= 73.7%

* Including 「partial interview」 and 「interview terminated before the screening question」
^ Including 「household-level refusal」 and 「known respondent refusal」

Table 2 Public survey - Breakdown of contact information

	Frequency	Percentage
Respondents' ineligibility confirmed	7,593	38.7%
Fax/ data line	850	4.3 %
Invalid number	5,867	29.9%
Call-forwarding/ mobile/ pager number	70	0.4%
Non-residential number	739	3.8%
Special technological difficulties	53	0.3%
No eligible respondents	14	0.1%

Respondents' ineligibility not confirmed	6,080	31.0%
Line busy	865	4.4 %
No answer	4,443	22.6%
Answering device	211	1.1%
Call-blocking	65	0.3%
Language problem	193	1.0%
Interview terminated before the screening question	297	1.5%
Others	6	0.0%

Respondents' eligibility confirmed, but failed to complete the interview	4,934	25.2%
Household-level refusal	7	0.0 %
Known respondent refusal	13	0.1%
Appointment date beyond the end of the fieldwork period	4,851	24.7%
Partial interview	43	0.2%
Miscellaneous	20	0.1%

Successful cases	1,011	5.2%

Total	19,618	100.0%