The title of the post is somewhat misleading in this instance: Video Gambling Machines (VDMs) in New Zealand exist in lots of places besides casinos. For that reason, self-exclusion from casinos alone would not be a very effective method for fighting gambling problems among those who patronize VDMs. New Zealand legislation provides that any gambling venue that permits a disassociated person to gamble could face significant penalties.
Peter Townsend (2007) presents the results of a study of a small sample (32 at the follow-up stage) of individuals who had self-excluded, as part of more comprehensive therapy for their gambling problems. The vast majority (26 of 32) report complete abstinence from gambling, and for those who continue to gamble, their gambling problems fall markedly, on average. Once again, self-exclusion (here, in combination with other measures) seems to be a pretty effective tool against compulsive gambling.
Other posts in this series:
Does Casino Self-Exclusion Work? (V)
Does Casino Self-Exclusion Work? (IV)
Does Casino Self-Exclusion Work? (II)
Does Casino Self-Exclusion Work? (I)