effect was maintained during a 10-month followup;
the subjects averaged a 67% reduction from
baseline.
Several factors may have contributed to the
success of the program: the changing criterion
treatment, the individualized programs for each
subject, the self-monitoring procedures, positive
feedback, the deposit and contract, and the positive
and negative short- and long-term monetary
consequences. However, at this time, we
do not know which factors, either singularly or
in combination, produced the treatment effect
because no component analysis was conducted.
Although doubtful, it is possible that none of
the program components were necessary and
that other factors were responsible for the treatment
effect. Other factors that could have influenced
the subjects include: (1) the information
they received on the deleterious effects of
caffeine and on the relative amounts of caffeine
in various beverages; (2) the minimal encouragement
they received from the experimenters;