The purpose of this study is to examine how the 'Best Possible Self' (BPS) intervention influences diabetes symptomatology over a four week period by assessing stress and resilience as mediatory effects. Half of the participants will receive the BPS straight away while the other half will be put on a waiting list and will act as the control group.

The BPS is a "positive" psychology intervention; i.e. it facilitates positive emotion in order to achieve psychological, behavioural, and even physiological changes. The present team's previous research has demonstrated that the BPS is effective at reducing certain diabetes symptoms, though the exact mechanisms by which it does so are unclear. According to the Stress Buffering Model of Physical Activity, psychological stress is the catalyst that triggers behavioural and physiological responses critical to health while positive emotions can improve health by helping people to cope. The Broaden and Build Theory of Positive Emotions, meanwhile, suggests that this is because positive emotions allow people to build resilience.

In this study, the aim is to examine whether stress and resilience in particular mediate the relationship between intervention and diabetes symptoms. Research around stress and resilience has shown these factors to be important not only in the physical health of people with diabetes but for also decreasing illness symptomatology in non-clinical samples more generally.

Inclusion Criteria:

• Non-clinical sample
• 18+
• Access to the internet

Exclusion Criteria:

• Severe mental illness (such as schizophrenia or bipolar depression)

We have no plans to share individual participant data.