Evidence-Based Treatment for Mental Health, Trauma, and Addiction: The Way Forward

In any given year, 1 in 5 Canadians experience a mental health condition or addiction.[i] Yet, 40 to 60% of people with a substance use disorder relapse—similar to relapse rates of other chronic illnesses, such as diabetes and asthma.[ii] On average, 520 per 100,000 Canadians are re-admitted to hospital every year for a mental health condition.[iii] With high relapse and hospitalization rates, poor mental health is not only devastating, it also costs the Canadian economy over $50 billion per year.1

Despite mental health’s far-reaching impact, not everyone is getting the quality of treatment they desperately need. A 2016 study found that only 13% of British Columbians with depression received adequate psychotherapy or counselling.[iv] Psychotherapy, or “talk therapy,” when practiced by a qualified professional, can be effective at treating mental health conditions alone or in conjunction with medication.[v] Knowing this, we need to make proven and effective psychotherapies more accessible.

Over the years, countless mental health treatments have been practiced, yet they remain largely unregulated. Treatment practices aren’t standardized for a variety of reasons, including:

  • gaps in knowledge about the biopsychosocial factors that cause mental health conditions and, thus, how to treat them;
  • a lack of understanding and training about the differences between psychotherapies—just as all drugs aren’t the same, neither are therapies;
  • a lack of resources, namely time and money, to provide the best possible treatment for each patient; and
  • a lack of well-designed and reproducible research on treatments.[vi],[vii]

To address this issue, health care providers need to implement evidence-based practices for mental health, trauma, and addiction. Mental health conditions are heterogeneous, so it’s imperative to individualize proven treatment programs to address a patient’s unique needs and preferences.[viii] This will ensure that patients receive treatments with a meaningful effect, while putting less economic strain on the healthcare system.

First, what are evidence-based practices?

Evidence-based practices are interventions with consistent scientific evidence showing that they improve patient outcomes.[vii] In other words, evidence-based practices come to be following several randomized clinical trials comparing the practice under investigation to alternative practices and/or to the current standard of care.[vii]

Common evidence-based psychotherapies used to treat mental health, trauma, and addiction include:

  • Cognitive Behavioural Therapy (CBT) has been shown to clinically improve Beck Depression Inventory scores after two weeks of treatment in 300 inpatients with depression.[ix]
  • Dialectical Behaviour Therapy (DBT) has been shown to significantly change parasuicidal behaviours, depression, and anxiety among 31 patients with borderline personality disorder who participated in a 3-month inpatient DBT program compared with 19 similar patients on a waiting list.[x]
  • Acceptance and Commitment Therapy (ACT) has been shown to increase the likelihood of opioid-dependent patients being opioid-free after a 24-week dose reduction outpatient program with weekly ACT sessions compared to drug counselling.[xi]
  • Cognitive Processing Therapy (CPT) has been shown to clinically reduce symptoms of post-traumatic stress disorder (PTSD), depression, and anxiety in sexual assault and veteran populations, with results maintained 5 and 10 years following treatment.[xii]

It’s essential to evaluate how a patient is responding to treatment, irrespective of the psychotherapy chosen. Progress and outcome measures assess whether a treatment actually improves a patient’s symptoms or functioning, allowing providers to plan, monitor, and adjust treatment options as needed.[xiii] Measures can screen individuals for mental health conditions, substance dependence, or PTSD (e.g., PHQ9, GAD-7, GAINSS, LDQ, and PCL) or assess an individual’s progress with a given psychotherapy (e.g., OQ-45). By determining what’s working and what’s not, an individualized treatment plan can be implemented—with constant tweaking—to provide the best approach for every patient.

Several other factors contribute to treatment success, too. One consideration is group versus individual therapy. Of course, there are advantages of each:

  • Group therapy can reduce stigma and isolation, spark new ideas for coping with challenges, allow for peer support to provide a sense of community,[xiv] and enable psychotherapists to assess behaviour in social situations.[xv]
  • Individual therapy can be tailored to an individual while providing confidentiality and a stronger relationship between patient and counsellor.[xvi]

A combination of group and individual therapy is preferable over individual counselling alone, particularly when one or the other hasn’t resulted in satisfactory progress. This way, the patient can reap the rewards of both therapy styles.

Likewise, the severity of a patient’s mental health condition and that patient’s living situation factor into whether an inpatient or outpatient program is most appropriate. Studies show comparative effectiveness between these two formats,[xvii] but one size doesn’t fit all. When comparing inpatient and outpatient treatments, we see that:

  • Inpatient care is intended for patients with severe symptoms and requires them to live in the treatment facility with access to 24/7 care. It is also used when outpatient services are not recommended or have been unsuccessful.
  • Outpatient programs are intended for patients with mild to moderate symptoms and who are able to sustain recovery without a high level of clinical supervision. These programs allow patients to live at home and maintain their daily routines, including employment.

When narrowing down further to an optimal treatment facility, standard of care and staff qualifications are noteworthy. Facilities should adhere to the best proven practices for each mental health condition. If providing a detox program or medication-assisted treatment, doctors and nurses should be present at facilities to provide medical supervision. Lastly, psychotherapy should be conducted by highly trained psychotherapists and counsellors.

An additional consideration for concurrent disorders is that treatment is most successful when all conditions are addressed in a coordinated manner.[xviii] For example, an individual might have an anxiety disorder and alcohol dependence requiring both mental health and addiction treatment.18 Since concurrent disorders likely affect each other, addressing them together often results in better outcomes for patients.

Mental health touches the lives of all Canadians. By providing individualized, evidence-based, and outcomes-focused treatment, together we can ameliorate the negative effects of the mental health crisis.


Whether you’re an individual who needs help with your mental health or substance use, or an employer or healthcare provider with a client in need of support, EHN Canada can help. We offer proven, best practices that treat concurrent disorders and support patients in achieving and maintaining long-term recovery. Call any of the numbers below, 24/7, to discover how our evidence-based treatments and qualified staff can help you.

  • Bellwood (Toronto, ON): 866-281-3012
  • Edgewood (Vancouver Island, BC): 604-210-8713
  • Ledgehill (Lawrencetown, NS): 866-419-4483
  • Sandstone (Calgary, AB): 866-295-8981
  • Gateway (Peterborough, Ontario): 705-874-2000
  • Nouveau Depart (Montreal, Quebec): 866-738-5572
  • Outpatient Services (Multiple locations): 866-345-8192


[i] Smetanin et al. (2011). The life and economic impact of major mental illnesses in Canada: 2011-2041. Prepared for the Mental Health Commission of Canada. Toronto: RiskAnalytica.

[ii] National Institute on Drug Abuse. (July 2020). Treatment and Recovery. Accessed on September 28, 2021 from: https://www.drugabuse.gov/publications/drugs-brains-behavior-science-addiction/treatment-recovery

[iii] Public Health Agency of Canada. (2019). Inequalities in mental illness hospitalization in Canada. Accessed on September 28, 2021 from: https://www.canada.ca/en/public-health/services/publications/science-research-data/inequalities-mental-illness-hospitalization-infographic.html

[iv] Puyat et al. (2016). How often do individuals with major depression receive minimally adequate treatment? A population-based data linkage study. The Canadian Journal of Psychiatry, 61(7):394-404.

[v] Seligman. (1995). The effectiveness of psychotherapy: The consumer reports study. American Psychologist, 50(12): 965-974.

[vi] Cohen et al. (2013). Evidence-based practice in mental health. Re$earch Infosource Inc. Publication. Accessed on September 28, 2021 from: https://cpa.ca/docs/File/Practice/Evidence_Based_Practice_inMentalHealth.pdf

[vii] Drake et al. (2001). Implementing evidence-based practices in routine mental health service settings. Psychiatric Services, 52(2):179-182.

[viii] Alda. (2013). Personalized psychiatry: many questions, fewer answers. J Psychiatry Neurosci, 38(6):363-5.

[ix] Page at al. (2012). Effectiveness of cognitive-behavioral therapy modified for inpatients with depression. International Scholarly Research Network Psychiatry:1-7.

[x] Bohus et al. (2004). Effectiveness of inpatient dialectical behavioral therapy for borderline personality disorder: a controlled trial. Behaviour Research and Therapy 42:487-499.

[xi] Stotts et al. (2015). The promise of third-wave behavioral therapies in the treatment of substance use disorders. Curr Opin Psychol, 2:75-81.

[xii] Watkins et al. (2018). Treating PTSD: a review of evidence-based psychotherapy interventions. Frontiers in Behavioral Neuroscience, 12:1-9.

[xiii] Kilbourne et al. (2018). Measuring and improving the quality of mental health care: a global perspective. World Psychiatry, 17(1): 30-38.

[xiv] Cyr et al. (2016). Making the case for peer support. Mental Health Commission of Canada. Accessed on October 4, 2021 from: https://www.mentalhealthcommission.ca//www/wp-content/uploads/drupal/2016-07/MHCC_Making_the_Case_for_Peer_Support_2016_Eng.pdf

[xv] CAMH. (2021). Health Info: Group Therapy. Accessed on September 28, 2021 from: https://www.camh.ca/en/health-info/mental-illness-and-addiction-index/group-therapy

[xvi] Mayo Clinic. (2016). Psychotherapy: Overview. Accessed on October 4, 2021 from: https://www.mayoclinic.org/tests-procedures/psychotherapy/about/pac-20384616

[xvii] Inpatient and outpatient treatment programs for substance use disorder: a review of clinical effectiveness and guidelines. Ottawa: CADTH; 2017 Nov. (CADTH rapid response report: summary with critical appraisal).

[xviii] Skinner at al. (2010). Concurrent substance use and mental health disorders: an information guide. Centre for Addiction and Mental Health. Accessed on September 28, 2021 from: https://www.camh.ca/-/media/files/guides-and-publications/concurrent-disorders-guide-en.pdf

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