Efficacy of an Autobiographical Memory Specificity Training for the Reduction of Depressive Symptomatology (PESCAR)

实验性的：Memory Training Group

This group will receive an online two-week intervention to train the specificity of autobiographical memories. During the two-week intervention and the following two weeks, participants will complete ecological-momentary assessments (EMA) to monitor the amount of positive and specific memories recalled during the day. EMA is an Experience Sampling Method assessment system that allows data to be collected from participants in their natural environment at various points in time (McDevitt-Murphy et al., 2018). For this study, we designed an EMA to monitor essential project variables throughout the intervention (2 weeks; from Day 0 to Day 15) and then as a follow-up (2 weeks after; from Day 16 to Day 30).

行为的：Autobiographical Memory Specificity Training PESCAR

An autobiographical memory specificity training has been developed by authors, based on previous training within the frame of Cognitive Bias Modification Interventions (CBM-I; Barry et al., 2019; Hitchcock et al., 2017). The training group will receive a self-guided intervention, which consists of an initial session (lasting 30 minutes approximately) and two-week training, conducted online. Participants will be provided with an online platform for following the intervention in a self-guided modality. The first session aims to give information about autobiographical memory functioning, to train in specificity recall through concrete processing steps and to explain the functioning of the self-guided modality. Then, during the next two weeks, participants will use the online platform once a day for practising the recall of autobiographical memories during 15-20 min approximately.

无干预：Control Group

This group will receive no intervention to train the specificity of autobiographical memories. During four weeks (from Day 0 to Day 30), participants will complete ecological-momentary assessments (EMA) to monitor the amount of positive and specific memories recalled during the day.

Autobiographical memory specificity. The Autobiographical Memory Test (AMT, Williams & Broadbent, 1986)

AMT is the preferred measure to evaluate the degree of specificity of autobiographical memory. During the AMT application, nine verbal cue words of different valence (three positive, three negative and three neutral) will be presented to the participants to perform a recall task of specific personal memories (Dritschel et al., 2014). The specificity of the memories is scored by evaluators following specified criteria (Williams et al., 2007), and then, an overall estimate of the level of specificity of autobiographical memories can be calculated. The assessment will be conducted online, following previous works with the written version of the AMT (Takano et al., 2017). The spanish adaptation (Ros et al., 2018) has shown adequate psychometric properties in young and older populations.

Depressive symptomatology. The Patient Health Questionnaire 9 (PHQ-9; Kroenke, Spitzer & Williams, 2001, Spanish adaptation Diez-Quevedo et al., 2001)

PHQ-9 is a nine-item self-report measure of depressive symptoms. Participants answer the statements using a four-point Likert scale (0= Not at all to 3=Nearly every day) (Kroenke, Spitzer & Williams, 2001). The Spanish version has shown comparable diagnostic validity to the original English version, presenting levels of 88% of sensitivity and 88% of specificity (Diez-Quevedo et al., 2001).

Savoring. Ways of Savoring Checklist (WOSC, Bryant & Veroff, 2007; Jose, Lim, & Bryant, 2012)

An abbreviated 19-item os WOSC assess the use of thoughts and behaviours that facilitate savoring by amplifying positive feelings (11 items; for example, "I thought about sharing the memory of this later with other people") and the use of thoughts and behaviours that inhibit savoring by dampening positive emotions (eight items; for example, "I told myself why I didn't deserve this good thing"). Participants indicated to what extent statements described their thoughts and behaviours during positive experiences over the past week (1 = definitely doesn't apply, 7 = definitely applies). Previous studies have reported good psychometric properties with αs = .85-.86 (Smith and Hanni, 2019).

Proportion of positive and negative memories recalled. (Ecological momentary assessment, EMA)

EMA involves repeated sampling of subjects' behaviours and experiences in real time and in their natural environments. EMA procedure aims to minimise recall bias, maximise ecological validity and allow the study of micro-processes that influence behaviour. Previous studies have demonstrated the utility and validity of this assessment strategy in a variety of clinical and subclinical contexts (Colombo et al., 2020a, b).For this study, participants will receive a notification (only once a day) on their smartphones asking about the ratio of positive to negative memories they have recalled during the day. This measure will be taken once a day, everyday during intervention (14 days: From Day 1 to day 15) and at follow-up (14 days; from Day 16 to Day 30))

Positive and negative affect. The Positive and Negative Affect Scale (PANAS; Watson et al., 1988; Sandín et al., 1999)

A self-report measure consisting of two sub-scales that assess the person's positive and negative affect. Each scale is composed of 10 items, giving a total of 20 items on a 5-point Likert scale (1=not at all/very mild; 5=extreme). The PANAS is established as a scale to measure changes in mood with excellent psychometric properties in the general population in its Spanish version (Sandín et al., 1999). In addition, its reliability and validity has recently been evaluated in the assessment of people with emotional disorders. It has shown good to excellent internal consistency in both subscales (Cronbach's alpha for positive affect = 0.91; Cronbach's alpha for negative affect = 0.87).

Well-being. Mental Health Continuum Scale (MHC: Keyes, 2004; Echevarría et al., 2010)

MHC-LF is a multidimensional measure, composed of 14 items measuring emotional (3 items), social (5 items) and psychological (6 items) well-being. It assesses the frequency with which they felt a certain way during the last month. Psychometric analyses of the Spanish validation (Echevarría et al., 2010) showed that it was a scale with good psychometric properties.