A Pilot Randomized Controlled Trial of an Intervention for Adults With Depression: the eMotion Study.

Depression will be measured using tThe Personal Health Questionnaire (PHQ-8). The PHQ-8 is an 8 item measure used to measure the frequency of depressive symptoms. This is a freely available brief self-report questionnaire which assesses depressive symptoms based on the Diagnostic and Statistical Manual for Mental Disorders (DSM-IV). Each item is rated on a scale of 0 to 3 with a maximum score of 24. It has been shown to have good validity, reliability, sensitivity and specificity. It has also been shown to discriminate between levels of major and major severe depression being 10-19, and 20-23 respectively (Kroenke et al., 2009)

Objective physical activity will be assessed using GeneACTIVE wrist worn accelerometers. The accelerometer is a small wrist worn device that measures and records acceleration. 1 minute epochs will be used to measure movement, with higher counts per minute reflecting higher levels of physical activity as recommended in previous studies (Helgadóttir, Forsell, & Ekblom, 2015; Mailey et al., 2010).

General Anxiety Disorder (GAD-7) is a 7 item scale which measures symptoms and severity of anxiety based on the DSM-IV criteria and included in the minimum IAPT data set (Spitzer, Kroenke, Williams, & Lowe, 2006).

Ecological Momentary Assessment of Mood (EMA) will be taken using a one item 10 point scale asking the participant to rate their mood where 1 = sad and 10 = happy. This will be taken twice per day randomly over five days during baseline data collection and at two months follow up using 'Text local', a text messaging service which allows participants to respond with a number response indicating their current mood at that point in time. This approach is adapted from previous research (van Rijsbergen, Bockting, Berking, Koeter, & Schene, 2012).

Self-reported physical activity will be measured using the short-form IPAQ which measures Minutes per week of moderate to vigorous physical activity will be assessed by using the International Physical Activity Questionnaire (IPAQ). The IPAQ is a valid cross national measure of self-reported physical activity (Craig et al., 2003).

The website will be assessed by asking questions understanding, perceived understanding the key learning goals for participants in all groups.

Fidelity of enactment will be measured by asking participants in all groups if they have carried out specific behaviour change techniques relating to physical activity, and behavioural activation along with rating confidence.

The Client Satisfaction Questionnaire - Short Form (CSQ-SF). This is a 4 item measure which will be used to assess participant satisfaction in eMotion 2 months post randomization.

Qualitative interviews after the final intervention session, all participants who receive eMotion will be invited to participate in a semi structured interview over the phone. The purpose of this is to further examine the acceptability of the intervention and any suggestions for improvement which can be absorbed into a next trial.