top of page

6. Does psychotherapy work?

Psychotherapy does work. Its effectiveness has been validated in numerous scientific studies over the past decades. Therefore, it is also covered by health insurance companies.

The effectiveness of psychotherapy was examined and confirmed for almost all mental disorders (such as anxiety, depression, addiction, personality disorder, post-traumatic disorder, attention deficit disorder and others). Therapy provides relief from acute mental suffering as well as long-term and lasting improvement.

In the terms of statistics, the size of the effect is measured by parameter called “effect size”. Zero means that the particular method has no effect, 0.2 is a limited effect, 0.5 medium effect. The success rate of therapy is 0.8, which is considered “very effective” (to compare, bypass surgery has the same effect size). In other words, a person undergoing therapy has a very high chance of feeling significantly better within a few months, compared to other suffering people.


Scientists sometimes say “one study = no study” and unfortunately in psychology it is twice as true. In addition to the usual limitations of research there are considerable methodological problems. It is quite complicated to numerically measure feelings, types of therapies, therapeutic styles and so on. Therefore, only studies which were succesfully replicated (ideally by a sceptic at the other end of the world) can be taken seriously. And in the best case scenario, 30+ studies is gradually done on a certain topic and we can summarize them in a so-called meta-analysis.

Meta-analyses are of great importance, because they point to a scientific consensus (a general scientific agreement on the subject). Here we present some highly quoted meta-analyses, published in prestigious scientific journals. Besides demonstrating the effectiveness of a particular form of therapy, its equivalence with other methods (including medication) is often confirmed, resulting in a cross-study verification.

  • Elliott, 2002 (summary)

    • A meta-analysis of 86 studies demonstrated the efficacy of humanistic therapies as well as the long term sustainability of the effects, and equivalence in comparison with other forms of therapy. 

    Shedler, 2010 (summary, fulltext)

    • The conclusion of this systematic review is that psychodynamic therapies are as efficient as other psychotherapeutic forms of treatments.

    Hofmann et al., 2012 (summary, fulltext)

    • The highly structured nature of cognitive-behavioural therapy allows for easier scientific evaluation, resulting in higher number of studies. Therefore we can even provide a "review of multiple meta-analysis”, which summarises the efficacy of CBT for a wide range of mental disorders.

    Hans, 2013 (summaryfulltext)

    • Meta-analysis of CBT for a particular diagnosis (depression, high effectiveness). 

  • Leichsenring et al., 2015 (summary, fulltext)

    • By analysis of 64 studies (3,086 patients) the authors conclude that psychodynamic tradition is efficient and equivalent to other psychotherapeutic methods.

  • Angus et al., 2015 (summary, fulltext)​

    • The authors present a summary of the research on humanistic therapy conducted from 1990 to 2015 (191 studies). The result prove efficiency, equivalency with other forms of therapy and long-term sustainability of positive results (even further improvements after finishing the therapy, see page 4).

  • Steinert et al., 2017 (summary, fulltext)

    • Analysis of 23 studies (altogether 2,751 patients) again confirmed that psychodynamic therapy is as effective as pharmacological treatment or CBT (respectively the differences of the effect size of these methods were marginal). 

  • ​Flückiger et al., 2018 (summary, fulltext)

    • The newest meta-analysis confirmed a strong influence of therapeutic relationship (so-called alliance) at the success of therapy (effect size about 0.6). The sample involved about 30,000 people and the result was found to be independent of both the form of therapy and client's characteristics. 

If you want to know more about current research in psychotherapy, you can continue here.

bottom of page