Australia's Gambling Industries - Productivity Commission

population would most likely have played in any single week in the twelve month
period. The approach used was as follows:
• those who participated at least once per week can be assumed to have
participated in any given week;
• those who participated between 1 and 3 times per month were assumed to have a
24/52 probability of participating in any given week; and
• those who participated less frequently than once per month were assumed to
have a 5/52 probability of participating in any given week.
On this basis, results from the National Gambling Survey suggest that around 50 per
cent of the adult population would have participated in some form of gambling
activity in a typical week in 1998-99. Allowing for differences in time periods and
gambling activities captured in the surveys, the similarity of the gambling
prevalence estimates (48 and 50 per cent) suggests that respondents to the National
Gambling Survey are likely to be representative of the adult population as a whole in
relation to the gambler/non-gambler split.
Phase 2 — the main questionnaire
Of the 3809 participants who were offered a phase 2 interview, fully completed
questionnaires were obtained from 3498 — a participation rate of 92 per cent. These
completed interviews comprised: 1225 regular gamblers, 1290 non-regular gamblers
and 983 non gamblers. The 1225 regulars comprised 889 respondents who
participated in any single gambling activity (apart from lottery games or instant
scratch tickets) at least once per week, or whose overall participation in gambling
activities (apart from lottery games or instant scratch tickets) was the equivalent of
weekly; and 336 ‘big spending’ and other respondents transferred from the nonregular
category by filter 3.
F.11 The questionnaire
The CATI version of the National Gambling Survey is attached.
F.30 GAMBLING