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Background: Previous studies on reporting bias generally examined whether trials were published in stand-alone publications. In this study, we investigated whether pooled-trials publications constitute a specific form of reporting bias. We assessed whether negative trials were more likely to be exclusively published in pooled-trials publications than positive trials and examined the research questions, individual trial results, and conclusions presented in these articles., Methods: Data from a cohort of 105 randomized controlled trials of 16 antidepressants were extracted from earlier publications and the corresponding Food and Drug Administration (FDA) reviews. A systematic literature search was conducted to identify pooled-trials publications., Results: We found 107 pooled-trials publications that reported results of 23 (72%) of 32 trials not published in stand-alone publications. Only two (3.8%) of 54 positive trials were published exclusively in pooled-trials publications, compared with 21 (41.1%) of 51 negative trials (p < 0.001). Thirteen (12%) of 107 publications had as primary aim to present data on the trial's primary research question (drug efficacy compared with placebo). Only four of these publications, reporting on five (22%) trials, presented individual efficacy data for the primary research question. Additionally, only five (5%) of 107 pooled-trials publications had a negative conclusion., Conclusions: Compared with positive trials, negative trials of antidepressants for depression were much more likely to be reported exclusively in pooled-trials publications. Pooled-trials publications flood the evidence base with often-redundant articles that, instead of addressing the original primary research question, present (positive) results on secondary questions. Therefore, pooled-trials publications distort the apparent risk-benefit profile of antidepressants.

Background: Improvement in depression within the first 2 weeks of antidepressant treatment predicts good outcomes, but non-improvers can still respond or remit, whereas improvers often do not.AimsWe aimed to investigate whether early improvement of individual depressive symptoms better predicts response or remission., Method: We obtained individual patient data of 30 trials comprising 2184 placebo-treated and 6058 antidepressant-treated participants. Primary outcome was week 6 response; secondary outcomes were week 6 remission and week 12 response and remission. We compared models that only included improvement in total score by week 2 (total improvement model) with models that also included improvement in individual symptoms., Results: For week 6 response, the area under the receiver operating characteristic curve and negative and positive predictive values of the total improvement model were 0.73, 0.67 and 0.74 compared with 0.77, 0.70 and 0.71 for the item improvement model. Model performance decreased for week 12 outcomes. Of predicted non-responders, 29% actually did respond by week 6 and 43% by week 12, which was decreased from the baseline (overall) probabilities of 51% by week 6 and 69% by week 12. In post hoc analyses with continuous rather than dichotomous early improvement, including individual items did not enhance model performance., Conclusions: Examining individual symptoms adds little to the predictive ability of early improvement. Additionally, early non-improvement does not rule out response or remission, particularly after 12 rather than 6 weeks. Therefore, our findings suggest that routinely adapting pharmacological treatment because of limited early improvement would often be premature.Declaration of interestNone.

Background: Antidepressants remain controversial, partly due to allegations that disappointing results were buried and because of their modest average efficacy.
AIM: To investigate bias in the antidepressant literature and the possibilities for predicting which patients with depression or anxiety do receive significant benefits from antidepressants.
METHOD: We investigated bias by comparing information from the US Food and Drug Administration with the published literature. To predict response, we used patient data from randomized trials.
RESULTS: Of all studies on depression or anxiety, 50% and 72% were positive, compared to 95% and 96% of all published studies. Safety outcomes were poorly reported in published articles and unpublished studies were often 'bundled' into pooled-trials publications with positive conclusions. We found an association between severity and antidepressant efficacy for some, but not all, anxiety disorders; previous research has found inconsistent evidence for this association for depression. Furthermore, patients with depression that showed early improvement were more likely to attain a good response, irrespective of which symptoms improved.
CONCLUSION: These results demonstrate the severe impact of bias on the antidepressant literature. Severity and early improvement predicted a good response, but more information is needed to improve predictions. The increased accessibility of individual patient data will hopefully soon enable further progress in this area.

Background: It has been suggested that antidepressant benefits are smaller for mild than severe depression. Because antidepressants are also used for anxiety disorders, obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD), we examined the influence of severity for these disorders., Methods: We used individual patient data of eight trials (3,430 participants) for generalized anxiety disorder (GAD); four trials (1,195 participants) for social anxiety disorder (SAD); four trials (1,132 participants) for OCD; three trials (1,071 participants) for PTSD; and 10 trials (2,151 participants) for panic disorder (PD). Mixed-effects models were used to investigate an interaction between severity and treatment group., Results: For GAD and PD, severity moderated antidepressant efficacy. The antidepressant-placebo difference was 1.4 (95% CI: 0.4-2.5; SMD: 0.21) Hamilton Anxiety Rating Scale (HAM-A) points for participants with mild GAD (baseline HAM-A = 10), increasing to 4.0 (3.4-4.6; SMD: 0.45) or greater for severely ill participants (HAM-A ≥ 30). For PD, the difference was 0.4 (0.3-0.6) panic attacks/2 weeks for participants with 10 panic attacks/2 weeks at baseline, increasing to 4.7 (3.0-6.4) for participants with 40. For SAD, OCD, and PTSD, no interaction was found. Across severity levels, the differences were 16.1 (12.9-19.3; SMD: 0.59) Liebowitz Social Anxiety Scale points, 3.4 (2.5-4.4, SMD: 0.39) Yale-Brown Obsessive-Compulsive Scale points, and 10.3 (6.9-13.6; SMD: 0.41) Clinician-Administered PTSD Scale points., Conclusions: Antidepressants are equally effective across severity levels for SAD, OCD, and PTSD. For GAD and PD, however, benefits are small at low severity, and the benefit-risk ratio may be unfavorable for these patients., (© 2018 Wiley Periodicals, Inc.)

Objective: To examine if Dutch physicians adhere to the national guidelines on the treatment of depression in children and adolescents., Design: Retrospective database research., Method: Data on children and adolescents aged between 6 and 17 years were selected from the IADB, a Dutch database of filled prescriptions. We examined whether children and adolescents were prescribed fluoxetine as recommended by the guideline, and whether the starting dose was in accordance with the guideline., Results: Of 2942 children and adolescents in whom antidepressant treatment was initiated, the proportion prescribed fluoxetine increased from 10.1% in 1994-2003 to 19.7% in 2010-2014. However, paroxetine (1994-2003) and citalopram (2004-2014) were the most frequently prescribed antidepressants. Starting doses were guideline-concordant in 58% of children, 31% of preadolescents and 16% of adolescents. Sixty percent of all adolescents were prescribed an adult starting dose., Conclusion: Guideline adherence was poor. In contrast to the guidelines, physicians preferred citalopram to fluoxetine in children and adolescents with depression. Furthermore, adolescents often received an adult starting dose. These results suggest that dedicated effort is necessary to improve guideline adherence.