Transdiagnostic group cognitive behavioural therapy for emotional disorders in primary care: The results of the PsicAP randomized controlled trial

Psychological Medicine cambridge.org/psm Original Article Cite this article: Cano-Vindel A, MuñozNavarro R, Moriana JA, Ruiz-Rodríguez P, Medrano LA, González-Blanch C (2021). Transdiagnostic group cognitive behavioural therapy for emotional disorders in primary care: the results of the PsicAP randomized controlled trial. Psychological Medicine 1–13. https://doi.org/10.1017/S0033291720005498 Received: 31 July 2020 Revised: 28 November 2020 Accepted: 30 December 2020 Key words: Anxiety; depression; emotional disorders; group psychotherapy; randomized clinical trial; somatization; transdiagnostic Author for correspondence: Roger Muñoz Navarro, E-mail: [email protected] © The Author(s), 2021. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons AttributionNonCommercial-NoDerivatives licence (http:// creativecommons.org/licenses/by-nc-nd/4.0), which permits non-commercial re-use, distribution, and reproduction in any medium, provided that no alterations are made and the original article is properly cited. The written permission of Cambridge University Press must be obtained prior to any commercial use and/or adaptation of the article. Transdiagnostic group cognitive behavioural therapy for emotional disorders in primary care: the results of the PsicAP randomized controlled trial Antonio Cano-Vindel1, Roger Muñoz-Navarro2, Juan A. Moriana3, Paloma Ruiz-Rodríguez4, Leonardo Adrián Medrano5and César González-Blanch6 1 Faculty of Psychology, Complutense University of Madrid, Campus de Somosaguas, s/n, 28223 Madrid, Spain; 2 Department of Psychology and Sociology, Faculty of Social and Human Sciences, University of Zaragoza, C/Cdad. Escolar, S/N, 44003, Teruel, Spain; 3 Department of Psychology, University of Córdoba/ Maimónides Institute for Research in Biomedicine of Cordoba-IMIBIC/Reina Sofía University Hospital, Av. Menéndez Pidal, s/n, 14004 Córdoba, Spain; 4 Castilla La Nueva Primary Care Centre, Health Service of Madrid, Calle Teruel, 4, 28941 Fuenlabrada, Madrid, Spain; 5 Faculty of Psychology, University Siglo 21, De los Latinos 8555, 5008 Córdoba, Argentina and 6 Mental Health Centre, University Hospital “Marqués de Valdecilla”- IDIVAL, Av. Valdecilla, 25, 39008 Santander, Cantabria, Spain Abstract Background. Emotional disorders are highly prevalent in primary care. We aimed to determine whether a transdiagnostic psychological therapy plus treatment-as-usual (TAU) is more efficacious than TAU alone in primary care adult patients. Methods. A randomized, two-arm, single-blind clinical trial was conducted in 22 primary care centres in Spain. A total of 1061 adult patients with emotional disorders were enrolled. The transdiagnostic protocol (n= 527) consisted of seven 90-min sessions (8–10 patients) delivered over a 12–14-week period. TAU (n= 534) consisted of regular consultations with a general practitioner. Primary outcome measures were self-reported symptoms of anxiety, depression, and somatizations. Secondary outcome measures were functioning and quality of life. Patients were assessed at baseline, post-treatment, and at 3, 6, and 12 months. Intention-to-treat and per-protocol analyses were performed. Results. Post-treatment primary outcomes were significantly better in the transdiagnostic group compared to TAU (anxiety: p< 0.001; Morris’sd=−0.65; depression: p< 0.001; d= −0.58, and somatic symptoms: p< 0.001; d=−0.40). These effects were sustained at the 12month follow-up (anxiety: p< 0.001; d=−0.44; depression: p< 0.001; d=−0.36 and somatic symptoms: p< 0.001; d=−0.32). The transdiagnostic group also had significantly better outcomes on functioning (d= 0.16–0.33) and quality of life domains (d= 0.24–0.42), with sustained improvement at the 12-month follow-up in functioning (d= 0.25–0.39) and quality of life (d= 0.58–0.72). Reliable recovery rates showed large between-group effect sizes (d> 0.80) in favour of the transdiagnostic group after treatment and at the 12-month follow-up. Conclusions. Adding a brief transdiagnostic psychological intervention to TAU may significantly improve outcomes in emotional disorders treated in primary care. Trial Registration. isrctn.org identifier: ISRCTN58437086 Introduction Emotional disorders –depression, anxiety, and somatoform disorders –are all highly prevalent in the community, imposing an enormous burden on society (Whiteford, Ferrari, Degenhardt, Feigin, & Vos, 2015). In particular, depression and anxiety represent a global burden that is even greater than the impact of chronic physical conditions (Vigo, Thornicroft, & Atun, 2016). Given the large negative consequences of these disorders, it is clear that mental health should be a major priority for all health systems (Patel et al., 2018). One approach to improving access to evidence-based treatments would be to integrate mental health care into the primary care setting (World Health Organization, 2018), where most patients with mild to moderate emotional disorders are treated (Kovess-Masfety et al., 2007). Many studies have shown that psychological therapy, mainly cognitive behavioural therapy (CBT), is an effective treatment for emotional disorders in primary care (Cuijpers et al., 2019b; Seekles et al., 2013). In recent years, several ambitious health care initiatives, such as the Improving Access to Psychological Therapies (IAPT) project in the UK, have been carried out to expand access to evidence-based psychological treatments for common mental disorders https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at to a wider population. The results of the IAPT and similar projects show that these initiatives are cost-effective (Layard & Clark, 2015) and highly beneficial for society (Clark, 2018; Wakefield et al., 2020). The pioneering IAPT project provided a model for similar international projects, such as those carried out in Australia (Cromarty, Drummond, Francis, Watson, & Battersby, 2016), Norway (Knapstad et al., 2018,2020), and Canada (Naeem, Pikard, Rao, Ayub, & Munshi, 2017). Nonetheless, several barriers to dissemination of psychological treatments have been identified (Harvey & Gumport, 2015), including the growing number of disorder-specific treatment guidelines (Newby, McKinnon, Kuyken, Gilbody, & Dalgleish, 2015), which may be particularly relevant in primary care where individuals with emotional disorders frequently present mixed symptoms attributable to different mental health disorders, and primary care providers often are not able to make a precise differential diagnosis due to time and other constraints (Tylee & Walters, 2007). In the past two decades, there has been a growing effort to develop psychological treatments based on a transdiagnostic approach, supported by evidence showing that many mental disorders share the same psychological processes implicated in the onset and maintenance of psychopathology (Aldao, Nolen-Hoeksema, & Schweizer, 2010; Norton & Hope, 2005; Patel et al., 2018). The available evidence suggests that transdiagnostic psychological therapy can be a highly effective treatment for emotional disorders (Newby et al., 2015). This therapeutic approach focuses on treating the common factors involved in many emotional disorders such as cognitive biases (Beck, 2019; Eysenck & Derakshan, 1997) and dysfunctional emotion regulation strategies (Sakiris & Berle, 2019; Sloan et al., 2017), which are both cognitive and behavioural (Naragon-Gainey, McMahon, & Chacko, 2017). Most recent research has focused on individual treatments –or, in some cases, virtual therapy (i.e. internet-based) –but few studies have tested the efficacyoftransdiagnostic group cognitive behavioural therapy (TD-GCBT) (Chamberlain & Norton, 2013; Norton & Barrera, 2012). The available evidence, although limited, suggests that the transdiagnostic group approach might be a particularly useful, cost-effective treatment given the high comorbidity among mental disorders, especially in primary care. As in many other European countries, the National Health System in Spain (Spanish acronym: SNS) is based on the principles of universal coverage, free access, and fairness. The SNS is primarily funded by taxes. The system itself is centred around primary care centres, with the population assigned to a given centre based on geographic proximity. Consequently, in this model, the general practitioners (GP) and nursing staff act as the gatekeepers to the SNS, except for emergency care. Primary care centres are staffed by multidisciplinary teams comprised by GPs, paediatricians, nurses, and administrative staff; some centres also have social workers, midwives, and/or physiotherapists. The core package of primary health care benefits compromises all health care prevention, diagnosis, treatment and rehabilitation services, including mental health. Unfortunately, in Spain, practically none of the regions has mental health professionals on staff at the primary care level. Rather, clinical psychologists working in specialized care can periodically be sent to primary care centres for mental health care issues, but this practice is very uncommon. Therefore, given the minimal presence of clinical psychologists in primary care, the provision of psychological therapy mainly relies on referral to specialized care, for which waiting times are typically long. Thus, most patients with emotional disorders are treated directly by their GPs, and this treatment tends to be medicationcentric, despite the recommendations provided by most clinical guidelines. The use of psychotropic drugs (mainly antidepressants, anxiolytics and hypnotics) has been increasing in Spain and their use is currently higher than in many other European countries (OECD, 2015). In this context, we conducted a randomized controlled trial (RCT) to compare TD-GCBT (7 sessions) plus treatment-as-usual (TAU) to TAU alone in adult patients with emotional disorders in the primary care setting. We hypothesized that TD-GCBT + TAU would be more effective than TAU alone in reducing anxiety, depression, and somatic symptoms, and that these benefits would be sustained 3, 6, and 12 months after treatment finalization. We further hypothesized that TD-GCBT + TAU would, compared to TAU alone, reduce disability, improve quality of life, and increase treatment satisfaction and that these benefits would also be sustained over time. Subjects and methods Study design The PsicAP trial was a multicentre, two-arm, single-blind, RCT. Patients were recruited in the primary care setting within the SNS with symptoms of an emotional disorder (depression, anxiety disorder, or somatization) and randomized to receive either TAU alone (control group) or combined treatment involving TD-GCBT + TAU. Participants Patients were recruited from 22 primary care centres in eight different regions in Spain (Andalusia, Basque region, Cantabria, Castilla la Mancha, Galicia, Madrid, Navarra, and Valencia) (Cano-Vindel et al., 2016). All patients who visited their GPs with signs or symptoms of negative or unpleasant emotional problems, moderate depression, anxiety, or somatic symptoms without any clear biological basis were considered candidates for study inclusion. Patients receiving treatment with antidepressants, anxiolytics, and/or hypnotics were also eligible and invited to participate by their treating GP. Recruitment The GPs explained the study to potential participants during the course of a routine clinical visit. Patients who agreed to participate were provided with patient information sheet with written details about the study and then asked to sign an informed consent form, after which an initial session with a psychologist was scheduled. At this visit, the study participants completed a battery of electronic questionnaires. The main study inclusion criteria were (1) age between 18 and 65 years and (2) the presence of symptoms suggestive of an emotional disorder, whose presence was initially assessed with the Patient Health Questionnaire (PHQ; Spitzer et al., 1999). Exclusion criteria included any of the following severe mental disorders: eating disorders; alcohol or substance abuse; bipolar disorder; severe major depressive disorder; recent suicide attempt, or other severe mental disorders diagnosed by the GP. The specific PHQ modules that assess for the presence of eating disorders and alcohol abuse were used to detect these conditions and to exclude patients with these disorders. Participants receiving psychological treatment for any mental disorder were also excluded. 2 Antonio Cano‐Vindel et al. https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at Randomization and masking A computer-generated allocation sequence was used to randomly assign patients (1:1) to receive either TD-GCBT + TAU or TAU alone. Study participants were contacted by email or phone to inform them of their treatment allocation. A clinical psychologist was assigned to lead a specific TD-GCBT intervention. Patients allocated to TAU were instructed to return to their GPs for treatment. None of the participants or clinicians was blinded to the treatment allocation. However, in accordance with the singleblind study design, the assessors involved in the preand posttreatment assessment phases were blinded to the allocation and did not participate in the interventions (TD-GCBT or TAU). The GPs did not receive any information from the researchers regarding baseline assessments, randomization, progress in the intervention, or other outcomes. Medical records and notes were not shared between the intervention team and primary care providers. Procedures Interventions The TD-GCBT protocol (Cano-Vindel et al., 2016; GonzálezBlanch et al., 2018b) was a planned program consisting of seven 90-min therapy sessions held over a 12–14-week period in small groups (8–10 patients) in the primary care centre. These sessions were led by trained clinical psychologists, which were not part of the primary care staff. In order to ensure the fidelity and consistence of the TD-GCBT treatment at all participating sites, all therapists were required to undergo an 8-h training program in the treatment protocol. This training session was led by a senior clinical psychologist. All therapists received a detailed, session-by-session outline of the treatment. The therapeutic approach was based on the transdiagnostic approach to emotional disorders, which assumes that most emotional disorders share several common factors (Aldao et al., 2010; Hofmann & Barlow, 2014), and that the onset and maintenance of emotional disorders are due to dysregulated cognitive-behavioural emotion regulation strategies (Aldao et al., 2010). Any participant who missed a training session was contacted by telephone by an assistant researcher and offered to attend the next session. At the start of each training session, the content of the previous session was briefly reviewed. The TAU intervention consisted of regular consultations with the treating GP, who assessed the patient’s physical and/or psychosocial complaints. GPs were instructed to treat patients in both arms in accordance with their best clinical judgment. In general, these treatments involved the prescription of anxiolytics, antidepressants, or hypnotics, and/or informal counselling/ support. Primary outcomes The primary outcome measure was the severity of symptoms of emotional disorders (anxiety, depression, and somatic symptoms), which were assessed by the relevant PHQ modules (Spitzer et al., 1999). The PHQ has been validated as a sensitive and specific test to determine the presence of these disorders based on the DSM-IV criteria. In a previous study that included a subset (15%, n= 178) of the patients in the current trial, we compared two PHQ modules to assess symptoms of anxiety (Muñoz-Navarro et al., 2017a) and depression (Muñoz-Navarro et al., 2017a) with clinical interviews (the gold standard) to validate these instruments in the present trial. Symptoms of Anxiety (GAD-7). The presence of anxiety was determined according to the Generalized Anxiety Disorder-7 scale (Spitzer et al., 2006). Total GAD-7 scores range from 0 to 21. For this trial, the cut-off for clinical significance on the GAD-7 was set at ⩾10. Internal consistency of the scale was good (α= 0.87). At this cut-off point, both sensitivity (0.87) and specificity (0.78) were acceptable (Muñoz-Navarro et al., 2017a). Mean scores were 12.3 (4.6) and the internal consistency of the scale was good (α= 0.87). Symptoms of Depression (PHQ-9). This PHQ module (Kroenke et al., 2001) was used to detect depression with a cut-off point of ⩾10. Total scores ranged from 10 to 23. Based on a previous study of this cut-off score (Muñoz-Navarro et al., 2017a), participants who scored from 20 to 23 were assigned to undergo a second-order assessment (interview with a clinical psychologist) to confirm the presence of moderate or severe depression disorder. Based on this clinical assessment, the patients were included or not in the trial (Cano-Vindel et al., 2016). The mean score on the PHQ-9 was 13.6 (5.4) and the scale showed a good internal consistency (α= 0.86). The most widely used cut-off score in the literature (⩾10) was used as the threshold for caseness, as this cut point presents a reliable balance between sensitivity and specificity (Kroenke et al., 2001). Symptoms of somatizations (PHQ-15). On the Spanish version of the PHQ (Spitzer et al., 1999), patients rate 13 somatic symptoms on a scale from 0 to 2, as follows: 0 (not bothered), 1 (bothered a little), or 2 (bothered a lot). Two items from the depression module (sleep and tiredness) are added and scored as follows: 0 (not at all), 1 (several days), or 2 (more than half the days or nearly every day). The reliability of this scale was acceptable (α= 0.80), with a mean score of 14.0 (4.8). Somatic symptoms were assessed according to the PHQ-15 sum score, with a maximum score of 30. Patient inclusion was based on an algorithm with the 13 somatic symptoms (patients with ⩾3 symptoms were classified as ‘bothered a lot’). A previous study used this algorithm to determine the sensitivity (78%) and specificity (71%) of the PHQ-15 (Kroenke et al., 2010). Secondary outcomes Functional Status. Secondary outcome measures included the level of disability on daily life domains (work, social, and family life) measured with the Sheehan Disability Scale (SDS; Luciano et al., 2010). The internal consistency of this scale was good (α= 0.80). Quality of Life. Quality of life domains (physical, psychological, social, and environmental) was evaluated with the World Health Organization Quality of life Instrument-Abbreviated version (WhoQoL-Bref; Lucas-Carrasco, 2012). Internal consistency for all factors was acceptable (α> 0.70): (physical: α= 0.77; psychological: α= 0.79; social: α= 0.70; environmental: α= 0.79). Treatment Satisfaction. Treatment satisfaction for the groups was assessed through a single question (‘Rate your satisfaction with the treatment received’) with responses given on a 10-point scale ranging from 0 (totally unsatisfied) and 10 (totally satisfied). Statistical methods Power and Sample size. To detect a minimally important effect size of ⩾0.2 with an alpha error probability of 0.05 and a power Psychological Medicine 3 https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at (1–β) of 0.80 using G*Power 3.1 for SPSS (Faul, Erdfelder, Lang, & Buchner, 2007), a sample size of 394 participants per group would be required. Anticipating a dropout rate of 25%, the necessary sample size would be 525 participants per group. For all results, we applied 95% confidence intervals (CI). Main Analyses. For primary outcomes, we considered group differences in anxiety (GAD-7), depression (PHQ-9), and somatic symptoms (PHQ-15) comparing baseline and post-treatment scores using a mixed-effect model. A mixed-effects model was computed, including time and treatment group as fixed effects and single participants as a random effect; group differences were analysed after controlling for baseline characteristics: gender, age, and treatment centre. For secondary outcomes, we similarly checked between-group differences in the level of disability on daily life domains (work, social, and family life) and quality of life domains (physical, psychological, social, and environmental). We performed an intention-to-treat (ITT) analysis that included all randomized patients using the chained equations multiple imputation procedure in the SPSS statistical software program, with five imputations. The effect sizes of the treatment on primary and secondary outcomes (mean scores) were calculated by applying Morris’sdstatistic. Morris (2008) described an effect size for the pre-post change (PPC) design, where the standardized effect of the treatment is defined as the difference between groups in mean PPC values, divided by the common standard deviation. The formula for the Morris’effect size is as follow: [δ PPC = (μ T2 –μ T1 )−(μ C2 –μ C1 )/σ], where μ gt is the mean of group g at time t, and σis the standard deviation of the untreated population. The main advantage of this formula is that it takes into account the mean and standard deviation of the sample both at the final assessment and at baseline, leading to a more representative effect size when the values differed from baseline. Additional analyses: Recovery, reliable recovery, and deterioration rates were calculated. The recovery index was defined as pretreatment scores above the threshold on any of the three scales and below the threshold on all scales at either the post-treatment or 12-month follow-up assessment. The reliable recovery rate was calculated using a change score based on the standard deviation (S.D.) and Cronbach’s alpha of each measure (as described in the IAPT project) to account for scale measurement errors (Clark et al., 2009). Thus, we used a change score of ⩾5 for the GAD-7 and ⩾6 for the PHQ-9 and the PHQ-15. Among the individuals who met the recovery criteria, individuals who scored below the caseness threshold on all three measures after treatment and showed reliable improvement on ⩾one of the three measures were considered to have achieved a reliable recovery. By contrast, deterioration was defined as an increase in the score on any of the three scales based on the criteria for the scale in question. All statistical analyses were two-tailed; given the multiplicity of comparisons for primary and secondary outcomes, the final alpha level was set at 0.01. Effect sizes for these analyses were calculated using Cohen’sd.Inaddition,a per-protocol (PP) analysis for primary and secondary outcomes was performed only in the patients who completed all follow-up measurements. Results A total of 1691 patients assessed between 14 January 2014 and 30 July 2018, were considered potential candidates for participation in this trial and were enrolled. Of those, 630 (37.3%) failed to meet all inclusion criteria, leaving a total of 1061 patients (62.7%) who met the trial inclusion criteria. These patients were then randomized to the treatment (n= 527) or control (n= 534) groups, and this sample (n= 1061) was used for the ITT analyses. Of these 1061 patients, 316 in the TAU group and 314 in the TD-GCBT + TAU group completed all post-treatment assessments (drop-out rate: 40.8 and 40.4%, respectively). The final 1-year follow-up assessments were completed by 30 July 2019. The study flow diagram is shown in Fig. 1. Participants in the experimental group attended a mean of 4.5 (S.D. = 2.6) of the seven sessions; 67.7% of the participants attended 4 or more sessions and were thus considered compliant. The number of TD-GCBT sessions attended was significantly correlated with post-treatment outcome measures: PHQ-9 (r=−0.14; p= 0.022), GAD-7 (r=−0.16; p= 0.008), and PHQ-15 (r=−0.16; p= 0.007), indicating that treatment exposure was associated with better outcomes. The sociodemographic characteristics of the sample are shown in Table 1. The most common patient profile was a married woman in her early 40s (mean age, 43.6; S.D., 12.3), employed part-time, earning less than €24 000 annually and presenting symptoms of at least three common disorders (depression, anxiety, and somatic). There were no significant between-group differences in TAU in terms of medications or dosage at the 12-month follow-up and visits to the GPs (data not shown, available upon request). Primary outcomes Anxiety symptoms (GAD-7) On the ITT analyses, there were significant between-group differences in anxiety symptoms at all post-treatment time points ( p< 0.001), with better results in the TD-GCBT + TAU group, with small to medium effect sizes (Morris’sd=−0.38 to −0.65). On the PP analysis, significant differences were also observed on all measures, but with medium to large effect sizes (Morris’sd= −0.62 to −1.01). Table 2 and Fig. 2 provide detailed results on these measures. Depression symptoms (PHQ-9) The ITT analyses revealed significant between-group differences (p< 0.001) after treatment finalization and at all follow-up assessments, with better outcomes in the TD-GCBT + TAU group, with small to medium effect sizes (Morris’sd=−0.36 to −0.58). The PP analyses also showed significant differences between the groups on all measures, with medium to large effect sizes (Morris’sd=−0.60 to −0.92). See Table 2 and Fig. 2 for more details. Somatization symptoms (PHQ-15) Significant between-group differences were detected at all posttreatment time points, indicating a greater reduction in somatic symptoms in the TD-GCBT + TAU group ( p< 0.001). Effect sizes ranged from small to medium (Morris’sd=−0.31 to −0.40). The PP analyses showed significant differences between the groups at all time points, with medium effect sizes (Morris’s d=−0.49 to −0.65). Table 2 and Fig. 2 provide more details. Recovery, reliable recovery, and deterioration rates In the ITT analyses (data shown as values and 95% CI), recovery rates for the TAU group at the post-treatment and 12-month 4 Antonio Cano‐Vindel et al. https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at assessments were 18% (14–22%) and 29% (22–36%), respectively. For the TD-GCBT + TAU group, the recovery rates at those same time points were 51.7% (46–57%) and 52% (45– 60%), yielding a between-group effect size of 0.76 (0.60–0.92) and 0.51 (0.36–0.67), respectively. The proportion of individuals considered to have achieved a reliable recovery at the post-treatment and 12-month assessments in the TAU group was 13.3% (9–17%) and 11% (5–16%), respectively; in the TD-GCBT + TAU group, the reliable recovery rates were 49.5% (44–55%) and 45% (37–48%), yielding a between-group effect size of 0.84 (0.68–1.05) and 0.83 (0.67–0.99), respectively. Deterioration rates at the post-treatment and 12-month assessments were 14% (10–17%) and 12% (7−14%) for the TAU group, and 3% (1–5%) and 3% (1–5%) for the TD-GCBT + TAU, yielding a between-group effect size of 0.41 (0.26–0.57) and 0.35 (0.19–0.50), respectively. Similar results were obtained on the PP analysis (data available on request). Fig. 1. Flow of participants through the trial. Psychological Medicine 5 https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at Secondary outcomes We observed (ITT analysis) a significantly greater decrease in the treatment group v. controls on all the three disability dimensions (work, social, and family life), with small effect sizes (Morris’d= −0.16 to −0.39). These differences were not significant at the 3-month follow-up but were significant at subsequent assessments (months 6 and 12). A similar result was found on the PP analysis, but with greater effect sizes, ranging from small to medium (Morris’d=−0.26 to −0.51) (Table 3). Small to medium effect sizes (Morris’d= 0.17–0.42) were found on the four quality of life dimensions assessed, with some variations at months 3 and Table 1. Demographics characteristics of sample Characteristics Total (n= 1061) Intention to treat sample Per protocol sample TAU (n= 534) TD-GCBT (n= 527) TAU (n= 316) TD-GCBT (n= 315) Gender Female 861 (81.1) 437 (81.8) 424 (80.5) 261 (82.6) 251 (79.7) Male 200 (18.9) 97 (18.2) 103 (19.5) 55 (17.4) 64 (20.3) Age group, years ⩽19 16 (1.5) 6 (1.1) 10 (1.9) 4 (1.3) 2 (0.6) 20–39 386 (36.4) 197 (36.9) 189 (35.9) 92 (29.1) 102 (32.4) 40–59 581 (54.8) 286 (53.6) 295 (56.0) 186 (58.9) 186 (59.0) ⩾60 78 (7.4) 45 (8.4) 33 (6.3) 34 (10.8) 25 (7.9) Marital status Married 513 (48.4) 248 (46.4) 265 (50.3) 159 (50.3) 177 (56.2) Divorced 87 (8.2) 34 (6.5) 53 (10.1) 21 (6.6) 28 (8.9) Widowed 29 (2.7) 14 (2.6) 15 (2.8) 10 (3.2) 6 (1.9) Separated 58 (5.5) 37 (6.9) 21 (4.0) 18 (5.7) 10 (3.2) Never married 212 (20.0) 102 (19.1) 110 (20.0) 56 (17.7) 51 (16.2) Unmarried 162 (15.3) 99 (18.5) 63 (12.0) 52 (16.5) 43 (13.7) Level of education No schooling 11 (1.0) 7 (1.3) 4 (0.8) 3 (0.9) 3 (1.0) Basic education 267 (25.2) 140 (26.2) 127 (24.1) 87 (27.5) 65 (20.6) Secondary education 233 (22.0) 122 (22.8) 111 (21.1) 68 (21.5) 59 (18.7) High School 262 (24.7) 123 (23.0) 139 (26.4) 79 (25.0) 94 (29.8) Bachelor 242 (22.8) 119 (22.3) 123 (23.3) 70 (22.2) 84 (26.7) Master/doctorate 46 (4.3) 23 (4.3) 23 (4.4) 9 (2.8) 10 (3.2) Employment situation Employed full-time 248 (14.7) 87 (16.3) 93 (17.6) 44 (13.9) 48 (15.2) Employed part-time 633 (37.4) 209 (39.1) 183 (34.7) 122 (38.6) 115 (36.5) Unemployed, in search of work 366 (21.6) 123 (23.0) 107 (20.3) 64 (20.3) 59 (18.7) Unemployed, not looking for work 202 (11.9) 60 (11.2) 77 (14.6) 40 (12.7) 49 (15.6) Temporary incapacity to work 129 (7.6) 32 (6.0) 41 (7.8) 25 (7.9) 26 (8.3) Permanent incapacity to work 37 (2.2) 10 (1.9) 13 (2.5) 9 (2.8) 9 (2.9) Retired 76 (4.5) 13 (2.4) 13 (2.5) 12 (3.8) 9 (2.9) Level of income (per year) Less than €12 000 euros 670 (39.6) 214 (40.0) 195 (37.0) 118 (37.3) 98 (30.5) Between €120 000 and €24 000 690 (40.8) 215 (40.2) 218 (41.4) 129 (40.8) 139 (44.6) Between €240 000 and €36 000 218 (12.9) 74 (13.9) 73 (13.9) 48 (15.2) 48 (15.7) More than €36 000 113 (6.7) 31 (5.8) 41 (7.8) 21 (6.6) 30 (9.2) TAU, treatment-as-usual; TD-GCBT, transdiagnostic group cognitive-behavioural therapy. Results are presented as number and percentages. 6 Antonio Cano‐Vindel et al. https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at Table 2. Summary of between-group differences in primary trial outcome Outcome measure Intention to treat sample Per protocol sample TAU TD-GCBT Difference TAU TD-GCBT Difference No. M (S.D.) No. M (S.D.) Morris’dp No. M (S.D.) No. M (S.D.) Morris’dp GAD-7 Baseline 534 –527 –– – – 534 12.1 (4.7) 527 12.5 (4.6) –0.264 Post-treatment 534 9.5 (5.4) 527 6.8 (4.7) −0.65 <0.001 316 10.2 (5.5) 315 6.0 (4.3) −1.01 <0.001 3 months 534 8.7 (5.3) 527 7.3 (5.0) −0.38 <0.001 238 8.9 (5.4) 273 6.7 (4.9) −0.62 <0.001 6 months 534 8.6 (5.4) 527 6.9 (5.1) −0.45 <0.001 204 8.8 (5.7) 229 6.2 (4.9) −0.78 <0.001 12 months 534 8.3 (5.7) 527 6.6 (5.4) −0.44 <0.001 180 8.7 (5.8) 208 5.8 (5.3) −0.91 <0.001 PHQ-9 Baseline 534 –– 527 –– – – 534 13.5 (5.4) 527 13.7 (5.3) –0.443 Post-treatment 534 10.8 (6.4) 527 8.0 (5.7) −0.58 <0.001 316 11.5 (6.6) 315 7.0 (5.2) −0.92 <0.001 3 months 534 10.2 (6.4) 527 8.4 (6.0) −0.39 <0.001 238 10.3 (6.5) 273 7.8 (6.0) −0.60 <0.001 6 months 534 9.8 (6.4) 527 7.9 (6.1) −0.40 <0.001 205 10.0 (6.6) 228 7.3 (6.1) −0.75 <0.001 12 months 534 9.4 (6.3) 527 7.8 (5.9) −0.36 <0.001 180 9.7 (6.5) 208 7.1 (6.2) −0.61 <0.001 PHQ-15 Baseline 534 –– 527 –– – – 534 14.0 (4.8) 527 14.3 (4.9) –0.388 Post-treatment 534 11.7 (5.2) 527 9.9 (5.4) −0.40 <0.001 316 12.1 (5.2) 315 9.1 (5.3) −0.65 <0.001 3 months 534 11.4 (5.1) 527 10.1 (5.3) −0.32 <0.001 238 11.7 (5.0) 273 9.5 (5.4) −0.49 <0.001 6 months 534 11.1 (5.3) 527 9.8 (5.6) −0.31 <0.001 205 11.5 (5.3) 228 9.2 (5.7) −0.59 <0.001 12 months 534 10.7 (5.6) 527 9.4 (5.6) −0.32 <0.001 180 11.7 (5.6) 208 8.8 (5.7) −0.57 <0.001 GAD-7, generalized anxiety disorder-7; M, mean; PHQ-9, Patient Health Questionnaire-9; PHQ-15, Patient Health Questionnaire-15, TAU, treatment-as-usual; TD-GCBT, transdiagnostic group cognitive-behavioural therapy; S.D., standard deviation. Psychological Medicine 7 https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at 6, and with medium effect sizes (Morris’d=0.55–0.72) at the final assessment (Table 3). The PP results were similar, but with larger effect sizes on almost all measures (Table 3). Overall, patients in the treatment arm were more satisfied than those in the TAU arm [9.75 (1.49) v. 7.72 (2.68)], which represents a large effect size (Morris’d> 0.90); however, this effect size decreased at subsequent follow-ups from a large to a medium-sized effect (Morris’d= 0.65 to 0.51). Discussion The main finding of this RCT is that adding TD-GCBT to TAU resulted in a greater reduction in the symptoms of emotional disorders at all post-treatment time points (immediately after treatment finalization, and at months 3, 6, and 12). The effect sizes for the primary outcomes were large for anxiety symptoms and medium for depressive and somatic symptoms. Furthermore, these therapeutic effects were sustained throughout the 12-month follow-up period, with small to large effect sizes. Importantly, the reliable recovery rates showed large effect sizes in favour of the experimental group at the immediate posttreatment assessment and at the 12-month-follow-up. Patients in the treatment group experienced a greater decrease in measures of disability significantly, a greater improvement in the quality of life and –as a consequence –higher treatment satisfaction immediately (scores >9 on a 10-point scale) after treatment completion and at the 12-month follow-up, thus supporting our secondary hypothesis that TD-GCBT + TAU would yield superior results to TAU alone on these measures. Of the patients in the TD-GCBT arm, approximately 70% attended four or more of the seven sessions, a finding that indicates the acceptability of the experimental intervention. These results are consistent with findings from previous studies, confirming the greater efficacy and effectiveness of adding CBT to TAU in the treatment of emotional disorders (Carpenter et al., 2018; Cuijpers et al., 2019a). Some studies have found that TD-CBT is highly effective in reducing the symptoms of anxiety and depression (Newby et al., 2015), as evidenced by the studies carried out by Norton and Barrera (Norton & Barrera, 2012) and Chamberlain and Norton (Chamberlain & Norton, 2013), both of which reported good results for TD-GCBT (mainly for anxiety disorders). In the primary care setting, however, relatively few studies have been conducted to evaluate individual or group TD-CBT, with the notable exception of a recent pre-post observational study (Kristjánsdóttir et al., 2018) that assessed a 6-week TD-GCBT intervention for adult patients with depression and/ or anxiety disorder. Reliable recovery rates in our trial were similar to those reported in other similar projects, such as the IAPT project in the UK, which achieved reliable recovery rates close to 50% on measures of anxiety and depression (Clark, 2018; Wakefield et al., 2020) and slightly lower than those reported in the Norwegian version of the IAPT (58.5%) (Knapstad et al., 2020). However, it is worth noting that we applied stricter, more conservative criteria, as we included three main outcomes (anxiety, depression, and somatizations) v. only two (anxiety and depression) in the IAPT programs. In fact, the between-group effect size in our study (>0.80) was larger than that observed in the Norwegian study (0.61). It is also important to emphasize that reliable deterioration rates in the experimental arm in our trial were notably lower than in the control group (3% v. 12–14%) as well as lower than the 5–10% deterioration rates commonly found in adult patients participating in clinical trials of psychotherapeutic therapies (Lambert & Ogles, 2004). In short, the findings of this large RCT support the efficacy of adding TD-GCBT to TAU in the primary care setting to treat patients with different emotional disorders. Our results show that this combined approach improves symptomatology and Fig. 2. Primary Outcomes at Baseline and Follow-up. TAU, treatment-as-usual; TD-GCBT, transdiagnostic group cognitive-behavioural therapy. Error bars represent standard errors. 8 Antonio Cano‐Vindel et al. https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at Table 3. Summary of between-group differences of secondary trial outcome Outcome measure Intention to treat sample Per protocol sample TAU TD-GCBT Difference TAU TD-GCBT Difference No. M (S.D.) No. M (S.D.) Morris’dp No. M (S.D.) No. M (S.D.) Morris’dp Working life a Baseline 534 3.5 (3.1) 527 3.6 (3.2) –0.600 534 3.5 (3.1) 527 3.6 (3.2) –0.604 Post-treatment 534 3.0 (3.1) 527 2.6 (3.0) −0.16 0.002 316 3.1 (3.1) 315 2.4 (2.9) −0.26 0.002 3 months 534 2.7 (3.0) 527 2.4 (3.0) –0.753 238 2.6 (3.0) 273 2.5 (2.9) –0.814 6 months 534 2.7 (83.0) 527 2.1 (2.9) −0.22 0.001 204 2.8 (3.0) 229 1.9 (2.7) −0.32 0.001 12 months 534 3.1 (3.3) 527 2.4 (3.2) −0.25 <0.001 180 3.3 (3.3) 208 2.0 (2.7) −0.44 <0.001 Social life a Baseline 534 4.6 (3.0) 527 4.7 (3.0) –0.965 534 4.6 (3.0) 527 4.7 (3.0) –0.946 Post-treatment 534 4.1 (3.1) 527 3.2 (3.0) −0.33 <0.001 316 4.1 (3.1) 315 2.9 (2.8) −0.41 <0.001 3 months 534 3.5 (3.1) 527 3.2 (2.9) –0.281 238 3.4 (3.2) 273 3.1 (2.9) –0.291 6 months 534 3.4 (3.2) 527 2.7 (3.1) −0.27 <0.001 205 3.6 (3.2) 228 2.6 (2.8) −0.36 <0.001 12 months 534 3.8 (3.4) 527 2.9 (3.4) −0.33 <0.001 180 4.0 (3.3) 208 2.6 (3.1) −0.48 <0.001 Family life a Baseline 534 4.6 (3.1) 527 4.8 (3.0) –0.437 534 4.6 (3.1) 527 4.8 (3.0) –0.430 Post-treatment 534 3.9 (3.1) 527 3.1 (2.9) −0.33 <0.001 316 4.0 (3.1) 315 2.8 (3.1) −0.43 <0.001 3 months 534 3.5 (3.1) 527 3.1 (3.1) –0.061 238 3.5 (3.1) 273 3.0 (3.0) –0.067 6 months 534 3.6 (3.2) 527 2.7 (3.1) −0.36 <0.001 205 3.6 (3.1) 228 2.6 (2.7) −0.41 <0.001 12 months 534 3.8 (3.3) 527 2.8 (3.2) −0.39 <0.001 180 3.9 (3.3) 208 2.5 (2.8) −0.51 <0.001 Physical b Baseline 534 22.4 (4.3) 527 22.1 (4.3) –0.327 534 22.4 (4.3) 527 22.1 (4.3) –0.327 Post-treatment 534 23.2 (4.5) 527 24.7 (4.6) 0.42 <0.001 316 22.7 (4.6) 315 25.1 (4.7) 0.61 <0.001 3 months 534 23.5 (4.6) 527 24.2 (4.8) 0.23 0.017 238 23.2 (4.8) 273 24.4 (4.9) 0.34 0.004 6 months 534 23.6 (4.5) 527 24.3 (4.4) 0.23 0.008 204 23.1 (4.8) 229 24.7 (4.9) 0.44 0.001 12 months 534 24.2 (5.1) 527 26.4 (5.3) 0.58 <0.001 180 22.7 (5.1) 208 25.6 (5.3) 0.73 <0.001 Psychological b Baseline 534 16.9 (3.8) 527 16.9 (3.8) –0.578 534 16.9 (3.8) 527 16.9 (3.8) –0.578 Post-treatment 534 17.7 (3.9) 527 19.2 (4.0) 0.39 <0.001 316 17.4 (4.2) 315 19.6 (4.0) 0.61 <0.001 3 months 534 18.1 (3.9) 527 18.9 (4.2) 0.21 0.001 238 18.0 (4.0) 273 19.3 (4.2) 0.38 <0.001 6 months 534 18.5 (3.8) 527 19.1 (3.9) 0.16 0.010 205 18.3 (4.2) 228 19.3 (4.2) 0.31 0.008 (Continued) Psychological Medicine 9 https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0033291720005498 Downloaded from https://www.cambridge.org/core. Universidad de Zaragoza, on 04 Mar 2021 at 11:02:34, subject to the Cambridge Core terms of use, available at