Objectives. Taylor & Gollwitzer (1995) suggested that optimistic biases abo
ut risk are not an impediment to precaution adoption. Their 'mindset hypoth
esis' proposes that such biases are suspended during deliberation over new
behaviours and reappear only later during thoughts about implementing these
behaviours. This paper examines the research on which the mindset hypothes
is was based and presents new data on this issue from an experiment designe
d to encourage home radon testing (Weinstein, Lyon, Sandman & Cuite, 1998).
Method. Homeowners (N = 1346) in an area of high radon risk watched either
a 'risk' video that gave information about the need to test, a 'how to test
' video that focused on the implementation of testing decisions, or both. R
isk perception biases were assessed before and after viewing the videos and
purchases of radon test kits were determined.
Results. No support was found for the mindset-illusions predictions. In con
trast, the data indicated that optimistic biases about personal risk are ba
rriers to action.
Conclusion. There are several methodological problems in the design used to
support the mindset-illusions hypothesis. In contrast to this hypothesis,
it appears that acceptance of personal vulnerability is an important aspect
of progress toward precaution adoption. The adaptiveness of optimistic bia
ses about risk is also discussed.