This series of studies is explored how the stability of sleep and activity patterns influences mood in three populations: individuals with fibromyalgia, individuals diagnosed with bipolar disorder and non-clinical individuals.

We were particularly investigating how appraisal style acts as a mediator variable in the relationship between circadian stability and mood in all the three populations.

Participants were asked to complete questionnaires assessing mood and appraisal style whilst also wearing a wristwatch which recorded activity levels over a seven day period.