Vazquez 2016.

Methods	Randomised controlled trial (pilot study) (November 2014 ‐December 2015)
Participants	Non‐professional caregivers of people with various conditions recruited from an official register of caregivers maintained by the Ministry of Labor and Welfare of the Government of the Autonomous Community of Galicia to North West Spain. Conditions included: diseases of the musculoskeletal system, connective tissue, cardiovascular and respiratory (19.7%, n = 12), chromosomal, congenital and perinatal abnormalities (23.0%, n = 14), mental disorders, neurological diseases, brain damage (18.0%, n = 11), dementia (39.3%, n = 24). Caregiver mean age was 58.4 (SD 8.0, range 42‐75 years). The majority (93.4%, n = 57) were female and 6.6% (n = 4) were male. Caregivers were caring for either father or mother (n = 21, 34.5%), son or daughter (n = 24, 39.3%) or other (n = 16, 26.2%) and had been involved in caregiving for an average of 12.3 years (SD 5.7) providing an average of 17.1 hours of care per day (SD 2.1). Forty caregivers (65.6%) were couples (married or had partners), 50.8% (n = 31) were of low or low middle social class, 49.2% (n = 30) were from middle, middle high or high social class. The majority (65.6%, n = 40) were literate or had a primary education; 34.4% (n = 21) had high school or university education. Most (63.9%, n = 39) had responsibility for housework and 36.1% (n = 22) were retired, employed or unemployed.
Interventions	Intervention: A cognitive behavioural intervention via group conference call (CBC) (n = 20) and a behavioural activation intervention through group conference call (BAC) (n = 22) (group delivered conference calls, approximately 5/group) Aim: To assess the feasibility/acceptability of a preventive cognitive‐behavioural intervention implemented via conference call for caregivers, and to conduct a preliminary assessment of the efficacy of the behavioural activation component alone compared to the complete cognitive behavioural intervention Interventionist(s): Four psychologists Mode of delivery: Telephone Duration: 5 weeks (weekly 90‐minute sessions) Content: Prior to the study, CBC and BAC intervention protocols were developed. The CBC intervention was based on a multifactorial integrative model of depression and was adapted from a proven indicated prevention program for depression previously implemented as a face‐to‐face group format. The BAC intervention was also adapted from prior work but in this case the intervention focused solely on the behavioural activation component. Standardisation: Training consisted of 35 hours for each of the interventions including contents, viewing videos, and role‐playing exercises and was administered by two clinical experts in both therapies, each with over 20 years of experience. Each intervention session was audio‐taped and protocol adherence was evaluated by one of two experienced clinicians. These clinicians also provided weekly therapist supervision. Therapist protocol adherence was 93% for CBC and 95% for BAC, indicating that the primary elements of the protocol were all administered. Comparison group: No intervention (n = 19)
Outcomes	1. Psychological health (depression) The Structured Clinical Interview for DSM‐IV Axis I Disorders Clinician Version (SCIDCV) IInstrument was used to assess Axis 1 disorders including major depressive disorders. The Center for Epidemiologic Studies Depression Scale (CES‐D‐Spanish version), which consists of 20 items with four Likert scale answer choices ranging from 0 (rarely or never) to 3 (most of the time). The total score ranges from 0 to 60, with a higher score corresponding to greater depressive symptomatology. 2. Satisfaction with the intervention: Client Satisfaction Questionnaire [CSQ‐8]. The CSQ‐8 is an 8‐item scale with 4 response options and a total score ranging from 8 to 32, with a higher score indicating greater satisfaction with the service received. Outcome data were collected at the end of intervention.
Notes	For the outcome depression, the reported results for 'The Center for Epidemiologic Studies Depression Scale (CES‐D‐Spanish version)' were used in the analysis for this review. On behalf of the principal investigator, Prof. Fernando L. Vázquez , Patricia Otero, PhD advised via email on the 6th August 2017 that at the time of this review a doctoral thesis was being finalised in which the efficacy of the clinical trial was being analysed. The pilot study for the trial which was published is included in this review for analysis. Patricia Otero PhD advised that the findings of the doctoral thesis are in the line with the pilot study. Details of the pilot study in terms of characteristics of the care‐recipients, the adaptation of the intervention, and intervention monitoring for the pilot study linked to this registered trial were provided by the study authors. Funding source: Work supported by the Ministry of Economy and Competitiveness of Spain (2012‐PN162 (PSI2012‐37396)) (p.594).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	An independent statistician randomly assigned participants to groups using the table of random numbers (p.939).
Allocation concealment (selection bias)	Unclear risk	Insufficient information to assess
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Unable to blind due to nature of the intervention
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"All pre‐ and post‐treatment assessments were conducted face‐to‐face by trained interviewers not directly involved in the research study and who were blind to the group to which each participant had been assigned" (p.940).
Incomplete outcome data (attrition bias) All outcomes	Low risk	Minimal attrition (2:2:1); balanced across groups and reasons provided (Figure 1, p.939)
Selective reporting (reporting bias)	Low risk	All relevant outcomes reported (p.943)
Other bias	Low risk	No remarkable or clinically relevant baseline differences, suggesting that randomisation had resulted in a balanced pilot study (p.940)