There is a growing body of research into the effectiveness of psychoanalytic psychotherapy.
Researchers have demonstrated good evidence for the positive effects of psychodynamic therapies for various psychological disorders, including depression, anxiety, post-traumatic stress disorder (PTSD) and eating disorders. The studies referred to here have evaluated either the general effectiveness of long- and short-term psychodynamic psychotherapy, or the impact of psychodynamic psychotherapy on specific illnesses. These studies are among an ever-increasing number being published and cited in eminent psychological, psychiatric and medical journals.
Examining the effectiveness of long-term psychodynamic psychotherapy (here meaning at least a year or 50 sessions) in complex mental disorders, a paper from 2011 found that long-term psychodynamic psychotherapy (LTPP) appears to be more effective than less intensive forms of psychotherapy in treating complex mental disorders.  Another paper reviewing LTPP on a larger scale compared 23 studies, involving a total of 1053 patients. It concluded that LTPP had a significantly higher rate of effectiveness in targeting problems and general personality functioning than shorter forms of psychotherapy.
A widely cited paper from 2010 summarized the evidence for the general effectiveness of psychodynamic psychotherapy. It concluded that psychodynamic therapy has as positive an impact on patients as other therapies, such as cognitive-behavioural therapy (CBT), that have been more readily promoted in modern healthcare What is more, patients who had psychodynamic therapy not only saw an improvement in their psychological difficulties during treatment, but this improvement continued after treatment had ended.
In a 2008 paper focusing on depression, researchers produced an overview of the effectiveness of psychoanalytic and psychodynamic therapies. The paper examined available evidence, and concluded that the benefits for patients of short-term psychodynamic therapies are equivalent to those produced by antidepressants and CBT.
Research has also been conducted into the impact of psychodynamic psychotherapy in specific psychological disorders. A 2007 study investigated the effects of psychodynamic psychotherapy in panic disorder. The researchers compared the effect on patients of panic-focused psychodynamic therapy versus relaxation training. There were 49 adults in the study, and they were all diagnosed with panic disorder. Many were also suffering from agoraphobia and/or depression. The participants who received psychodynamic treatment showed a significantly greater reduction of panic symptoms than those receiving relaxation training, as well as greater improvement in psychosocial functioning (the term ‘psychosocial’ refers to an individual’s psychological state in relation to social factors).
In 2011 researchers conducted a review of trials into the effect of short-term psychodynamic psychotherapy in patients with personality disorder. Looking at the results of eight studies, the researchers concluded that psychodynamic psychotherapy may be considered an effective treatment option for a range of personality disorders, producing significant and medium- to long-term improvements for a large percentage of patients.
Research has also been done into the cost-effectiveness of psychodynamic psychotherapy, which has often been regarded as too expensive to be funded in the public sector. In fact, a study of more than 100 patients who had received at least six months’ worth of NHS psychiatric treatment without improvement, found that psychodynamic psychotherapy resulted in both significant improvements in the patients’ symptoms and value for money. Not only did the patients’ mental health improve with psychodynamic psychotherapy, but they also spent fewer days as in-patients, had fewer GP consultations, required less contact with practice nurses, needed less medication and sought less informal care from relatives. Consequently the extra cost incurred through using psychodynamic treatment was recouped within only six months.
(Based on a research summary by Jessica Yakeley and Peter Hobson)
 Leichsenring, F., Rabung, S. (2011). Long-term psychodynamic psychotherapy in complex mental disorders: Update of a meta-analysis. The British Journal of Psychiatry, 199(1): 15-22.
 Leichsenring, F., & Rabung, S. (2008). Effectiveness of long-term psychodynamic psychotherapy. Journal of the American Medical Association, 300, 1151-1565.
 Shedler, J. (2010). The efficacy of psychodynamic psychotherapy. American Psychologist 65(2): 98-109.
 Taylor, D. (2008). Psychoanalytic and psychodynamic therapies for depression: the evidence base. Advances in Psychiatric Treatment, 14, 401-413.
 Milrod, B., et al (2007). A randomized controlled clinical trial of psychoanalytic psychotherapy for panic disorder. American Journal of Psychiatry, 164, 265-272.
 Town, J.M., Abbass, A., Hardy, G. (2011). Short-term psychodynamic psychotherapy for personality disorder: A critical review of randomized controlled trials. Journal of Personality Disorders, 25(6): 723-740.
 Guthrie, Moorey, Margison et al (1999). Cost-effectiveness of brief psychodynamic-interpersonal therapy in high utilizers of psychiatric services. Archives of General Psychiatry, 56, 519-526.