To evaluate the effect of a decision aid (DA) on women's knowledge of the benefits
and harms of screening and on their ability to make an informed decision.
An online randomized controlled trial among 321 women aged 38-45 years was conducted.
Participants were randomized to either immediate or delayed access to the online DA
which (i) explained the benefits and harms, (ii) included a values clarification exercise
and a worksheet to support decision making. The primary outcome, knowledge of benefits
and harms of screening, and secondary outcomes, informed choice (composite of knowledge,
values and intention), anxiety and acceptability of the DA were measured using online
questionnaires.
Women in the intervention group were more knowledgeable (mean score out of 10, 7.35
vs 6.27, p<0.001) and were more likely to have made a decision (82% vs 61% p<0.001).
Of those who made a decision, women in the intervention group were less likely to
start screening now (52% vs 65% p=0.05). There was no significant difference in the
proportion of women who made an informed choice (71% intervention group vs 64% control
group, p=0.24). The DA was helpful, balanced and clear, and did not make women anxious.
The DA increased knowledge and reduced indecision, without increasing feelings of
anxiety.
This decision aid is easy to access online and could be an inexpensive way of supporting
women aged 40 who are considering whether to start screening now, or wait until they
are 50. The results of this study demonstrate the potential of DAs to help inform
women about both the benefits and risks of screening at this age and to support women
and clinicians in this decision making process.
(c) 2010 Elsevier Ireland Ltd. All rights reserved.