Sick and Tired: Understanding and Managing Sleep Difficulties in ...

Based on the current research evidence, it was hypothesised that:
1) People with FMS would have significantly higher perceived levels of stress than
healthy controls;
2) People with FMS would have significantly higher dysfunctional beliefs about
sleep than healthy controls;
3) People with FMS would have higher levels of poor sleep quality than healthy
controls;
4) Higher levels of perceived stress and dysfunctional beliefs about sleep would be
associated with poorer sleep quality;
5) Poor sleep quality is a predictive factor in being diagnosed with FMS.
Power Calculations
A priori power calculation using G*power 3.1.0 based on a two-tailed, Mann Whitney
test, with a medium effect size of 0.5, alpha 0.05 and power 0.8 revealed that a
minimum of 128 participants (64 per group) would be needed for this study to have
power to detect significant differences between the two groups.
Participant Recruitment
As the recruitment procedure worked effectively in recruiting sufficient numbers of
participants with a range of symptom severity in the previous study, an identical
recruitment procedure was applied for this study. This involved advertising for
volunteers through patient support groups (see Chapter Four for details). To be included
in this study as „cases‟, participants were required to have received a diagnosis of FMS
by a GP or consultant. Due to financial limitations we were unable to confirm the
diagnosis of FMS. To elicit a comparative sample of „control‟ participants of a similar
age range, people without a diagnosis of FMS were recruited through community
groups run by the University of the Third Age (U3A) organisation. This organisation
runs community based activity and socialisation groups within the same regions of the
UK as FMS support groups. This approach also aimed to control for any factors relating
to being a member of a community group, such as increased social support.
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