Lifestyle Modification Program in the Prevention and Treatment of Depression

The primary outcome will be measured using the BDI-II (Beck et al., 1996). This is a self-report inventory for measuring the severity of depression, consisting of 21 multiple-choice questions with each answer being scored on a scale ranged from 0 to 3. It was translated and validated into Spanish with a reliability of .89 (Sanz et al., 2005). The standardized cutoffs are: 0-13: minimal depression; 14-19: mild depression; 20-28: moderate depression; 29-63: severe depression.

It is a short-term structured diagnostic interview that explores the main psychiatric disorders of Axis I of Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and International Classification of Diseases (ICD-10) (Ferrando et al., 2000).

Comorbidity with chronic diseases will be determined according to the International Classification of Diseases (ICD-10) (WHO, 2010): diabetes (glucose concentration (mg/dl), glycated hemoglobin (%), creatinine), arterial hypertension and diseases of lipid metabolism. In patients with chronic heart disease, coagulation variables will be added. They will be collected from the last blood test or control measurements of the clinical history, taken by their general practitioner (GP) or nurse (assuming they were taken over the past 3 months). Otherwise, their GP will be asked for a blood control test. It is estimated that approximately 50% of these patients will present some comorbidity (Katon, 2003). Anthropometric measures will also be collected (weight, size and perimeter of the waist).

Health-related quality of life will be measured using the European Quality of Life-5 Dimensions questionnaire (EQ-5D) (Brooks & De Charro, 1996; The EuroQol Group, 1990). EQ-5D scores will be used to calculate the quality-adjusted life year (QALY) during the monitoring period by adjusting the length of time affected by the health result by the utility value. It contains five health dimensions (mobility, selfcare, usual activities, pain/discomfort and anxiety/depression) and each of these has three levels (no problems, slight problems or moderate and severe problems). The EQ records the patient's self-rated health on a vertical visual analogue scale of 20 centimeters (VAS). The VAS can be used as a quantitative measure of health outcome that reflect the patient's own judgment. Patients mark the point on the vertical line that best reflects their assessment of their current global health status (Badia, Roset, Montserrat, Herdman, & Segura, 1999).

Physical activity will be measured using the International Physical Activity Questionnaire-Short Form (IPAQ-SF) (Kim, Park, & Kang, 2013). It assesses the levels of habitual physical activity over the last 7 days. It has 7 items and records the activity of four intensity levels: vigorous-intensity activity, moderate-intensity activity (walking and sitting). We will use the validated Spanish version (Roman-Viñas et al., 2010). IPAQ-SF has acceptable validity for the measurement of total and vigorous physical activity and poor validity for moderate activity and good reliability (Kurtze, Rangul, & Hustvedt, 2008).

Measured using the 14-item Mediterranean Diet Adherence Screener (MEDAS), developed within the PREDIMED study group (Martínez-González et al., 2010). It includes items on food consumption and intake habits: the use of olive oil as the main source of cooking fat, preference for white meat over red meat, servings of vegetables, portions of fruit, red meat or sausages, servings of animal fat, sugar-sweetened beverages, red wine, legumes, fish, commercial pastries and dressing food with a traditional sauce made of tomatoes, garlic, onion, or leeks sautéed in olive oil. The total score ranges from 0 to 14, with a higher score indicating a better accordance with the Mediterranean diet (Schröder et al., 2011).

Measured using the Pittsburgh Sleep Quality Index (PSQI) (Buysse, Reynolds, Monk, Berman, & Kupfer, 1989). To measure sleep quality and patterns in adults. It differentiates between "poor" and "good" sleep by measuring seven domains: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction over the past month. It consists of 19 self-applied questions and 5 questions that request the evaluation of the patient's bedmate or roommate (these are not scored). Answers range from 0 (no difficulty) to 3 (severe difficulty). The overall score ranges from 0 to 21 points. In its Spanish version, the Cronbach's alpha coefficient is .81, sensitivity of 88.63% and specificity of 74.99%. We will use the validated Spanish version (Royuela Rico & Macías Fernández, 1997).

Measured using the Patient Activation Questionnaire (PAM) with regard to the management of their health. It evaluates the patient's perceived knowledge, skills, and confidence to engage in self-management activities. It has 13 items, a Likert scale from 1 (strongly disagree) to 4 (strongly agree). The resulting score (between 0 and 100) places the individual at one of four levels of activation, each of which reveals insight into a range of health-related characteristics, including behaviors and outcomes. Higher scores indicate higher levels of activation (Hibbard et al., 2004). This scale is only validated in Spanish for chronic patients. It had an item separation index for the parameters of 6.64 and a reliability of .98 (Moreno Chico, González de Paz, Monforte Royo, Navarro Rubio, & Gallart Fernández Puebla, 2018).

It will be measured by the Medical Outcomes Study Social Support Survey (MOS-SS) (Sherbourne & Stewart, 1991). It is a self-report instrument consisting of four subscales (emotional/informational, tangible, affectionate, and positive social interaction) and an overall functional social support index. It has a good reliability (Cronbach's alpha ≥ .91) and is quite stable over time. It has 19 items, a five-point Likert scale. Higher scores indicate more support. We will use the Spanish validated version (de la Revilla-Ahumada L, Luna del Castillo J, & Bailón Muñoz E, 2005).

Measured using by the Self-Efficacy Scale (Sherer et al., 1982). To measure General Self-Efficacy subscale (17 items including individuals' beliefs in their ability to perform well in a variety of situations) and Social Self-Efficacy subscale (6 items). It contains 23 items that are rated on a 14-point scale (ranging from strongly agree to strongly disagree). Higher scores indicate higher levels of self-efficacy. It has a Cronbach coefficient alpha of .86 for General Self-efficacy subscale and .71 for the Social Self-efficacy subscale. The unpublished Spanish version was translated by Godoy in 1990 (Lopez-Torrecillas, García, Cañadas, Ramirez Ucles, & de la Fuente, 2006).

Measured using the Sense of Coherence (SOC) questionnaire by Antonovsky (Antonovsky, 1993). It values the personal disposition towards the assessment of vital experiences. It measures the sense of coherence, comprehensibility, manageability and meaningfulness. It has 13 items scoring between 13 and 91 points. It has consistency rates of between .84 and .93. Higher scores (after reversal of the inverted items) indicate a higher sense of coherence. We will use the validated Spanish version (Moreno, B., Alonso, M., & Álvaréz, 1997).

Measured using the Health Literacy Europe Questionnaire (HLS-EUQ16) (Sørensen et al., 2015). It can indicate that the probability of functional literacy in limited health is high, a possibility of functional literacy in limited health, and a functional health literacy in adequate health. It contains 16 items. Higher scores indicate better health literacy. It presents a high consistency (Cronbach's alpha of .982) in the Spanish validation (Nolasco et al., 2018).

Measured using the Irrational Procrastination Scale (IPS) (Steel, 2010). To measure general procrastination (dysfunctional delay). It has 9 items, rated on a 5-point Likert scale, with higher scores (after reversal of the three procrastination-inconsistent items) indicating a higher level of procrastination. Its Cronbach's alpha value is 0.90. We will use the validated Spanish version (Guilera et al., 2018).

It will be measured using the Client Service Receipt Inventory (CSRI) (Knapp, 2001). This data may be used for a wide range of applications, including estimates of the costs of service receipt. To collect information on the entire range of services and supports used by study participants. It retrospectively collects data on the use of services over the past 6 months (e.g., rates of use of individual services, mean intensity of service use, rates of accommodation use over time). We will use the validated Spanish version (Vazquez-Barquero, Gaite, Cuesta, Garcia, & Knapp, 1997).