Sunday, July 7, 2019

The effects of psychotherapy for depression are small; unadjusted meta-analyses of psychotherapies overestimate the effects considerably: only 23% of the studies are of low risk of bias

Was Eysenck right after all? A reassessment of the effects of psychotherapy for adult depression. P. Cuijpers, E. Karyotaki, M. Reijnders and D. D. Ebert. Epidemiology and Psychiatric Sciences, Volume 28, Issue 1, February 2019, pp. 21-30.

Aims; In the 1950s, Eysenck suggested that psychotherapies may not be effective at all. Twenty-five years later, the first meta-analysis of randomised controlled trials showed that the effects of psychotherapies were considerable and that Eysenck was wrong. However, since that time methods have become available to assess biases in meta-analyses.

Methods: We examined the influence of these biases on the effects of psychotherapies for adult depression, including risk of bias, publication bias and the exclusion of waiting list control groups.

Results: The unadjusted effect size of psychotherapies compared with control groups was g = 0.70 (limited to Western countries: g = 0.63), which corresponds to a number-needed-to-treat of 4.18. Only 23% of the studies could be considered as a low risk of bias. When adjusting for several sources of bias, the effect size across all types of therapies dropped to g = 0.31.

Conclusions: These results suggest that the effects of psychotherapy for depression are small, above the threshold that has been suggested as the minimal important difference in the treatment of depression, and Eysenck was probably wrong. However, this is still not certain because we could not adjust for all types of bias. Unadjusted meta-analyses of psychotherapies overestimate the effects considerably, and for several types of psychotherapy for adult depression, insufficient evidence is available that they are effective because too few low-risk studies were available, including problem-solving therapy, interpersonal psychotherapy and behavioural activation.

Check also Modest, yet progressive: Effective therapists tend to rate therapeutic change less positively than their patients. Max Ziem & Juergen Hoyer. Psychotherapy Research, Jun 21 2019,

And Rethinking psychotherapy. Dan J. Stein, Judith K. Bass, Stefan G. Hofmann, Mark van Ommeren. In Global Mental Health and Psychotherapy: Adapting Psychotherapy for Low- and Middle-Income Countries. 2019.

And Rolf Degen summarizing: After decades of research, we still don't have a clue about which specific components of psychotherapy are helpful for clients, or if there are even any...
The Role of Common Factors in Psychotherapy Outcomes. Pim Cuijpers, Mirjam Reijnders, and Marcus J.H. Huibers. Annual Review of Clinical Psychology, Vol. 15:- (Volume publication date May 2019).

And:  Found little evidence that the accumulation of treatment development & testing across decades increased psychotherapies benefit, 1960-2017
Are Psychotherapies for Young People Growing Stronger? Tracking Trends Over Time for Youth Anxiety, Depression, Attention-Deficit/Hyperactivity Disorder, and Conduct Problems. John R. Weisz et al. Perspectives on Psychological Science,

And  Depression treatments: The effects are probably overestimated, relapse rates for patients who respond are very high (about 50% over 2 years), there is little evidence for long-term effectiveness, & there are the problems of publication bias, sponsorship bias, & others
The Challenges of Improving Treatments for Depression. Pim Cuijpers. JAMA. Published online November 30, 2018.

And  Studies with the strongest research designs indicate that psychotherapy may be considerably less effective than we tend to believe; in fact, different psychotherapies may be equally ineffective
Insight Into Insight in Psychotherapy. Per H√łglend. American Journal of Psychiatry,

And  Psychotherapy: Rigorous training, supervision, trying the different methods, yield no improvement in more than forty years
The question of expertise in psychotherapy. Daryl Chow, Scott D. Miller, Mark A. Hubble. Journal of Expertise 2018. Vol. 1(2),

Gender differences in orthorexic eating behaviors: Women were more likely to report pathologically healthful eating than men

Gender differences in orthorexic eating behaviors: A systematic review and meta-analytic integration. Jana Strahler. Nutrition, July 4 2019.

•    This meta-analysis determines the size of gender differences in pathologically healthful eating.
•    Data from 67 studies including 39’255 participants is summarized.
•    Women were more likely to report pathologically healthful eating than men.
•    Similar effects sizes between general population and high-risk samples were shown.
•    Differences were inconsistently and minimally related to sample's mean age or year of publication.

Objective: Besides the ongoing debate about the epidemiological and clinical relevance of pathologically healthful eating, a phenomenon called orthorexia nervosa (ON), there is not much consensus about gender differences in prevalence rates. This study, therefore, provides a systematic review and meta-analytic combination of derived data to better conceptualize the presence and size of gender differences in the prevalence and levels of orthorexic eating behaviors and ON.

Research method: Sixty-seven publications were included in the synthesis providing data from k=89 subsamples (39’255 participants, 67.7% women) for meta-analytic procedures. Separate analyses were conducted for each measurement tool. The impact of four moderators proposed to explain gender differences was examined: sample composition (general population vs. special interest in health population; subgroup analysis), and in a meta-regression sample's mean age, year of publication, and gender distribution.

Results: The results showed significant gender differences in only one of four instruments in use. Studies measuring orthorexic behaviors showed that women were significantly more likely to report pathologically healthful eating than men (small effect size). Studies employing tools to assess tendencies towards healthy eating indicated similar levels in women and men. Subgroup and moderator analyses showed comparable effects sizes in general population and high-risk samples, and that the gender difference was inconsistently and minimally related to the sample's mean age, year of publication, or gender distribution.

Conclusions: The findings indicate that, depending on the instrument in use, tendencies towards healthy eating are comparable between the genders while pathologically healthful eating is slightly more pronounced in women. Future studies will have to adopt valid criteria for diagnosing Orthorexia nervosa and investigate additional factors contributing to pathological healthful eating and ON.

Level of evidence: Level IIa, Systematic review (with homogeneity) of cohort studies.