The use of placebos in randomized clinical trials of mood disorders: well justified, but improvements in design are indicated

Factors modifying drug and placebo responses in randomized trials for bipolar mania

Randomized placebo-controlled trials (RCTs) are standard for assessing efficacy and safety of treatments. We pursued preliminary indications that some factors are associated differentially with responses to placebo or drugs in RCTs for bipolar mania. We meta-analysed data from RCTs to assess influences of study-site count, subjects' age, sex distribution, diagnostic subgroups, clinical features, trial-completion rates, and publication year on mean difference (MD) in mania ratings between intake and final assessments. In 38 RCTs involving 3812 placebo-treated and 6988 drug-treated patients, symptomatic improvement was similar in placebo arms of trials of effective (6.77, 95% CI 5.77-7.76) and ineffective (7.61, 95% CI 5.47-8.75) drugs. Lesser placebo responses (MD) and greater drug-placebo differences (Hedges' g) were associated with fewer study sites, younger patients' age, and male sex. More patients with initial psychotic features and more trial completion in drug arms were associated with greater drug-associated improvement (MD) and drug-placebo contrast (Hedges' g), whereas more mixed-state diagnoses decreased both measures. Identifying modifying factors can support more efficient and cost-effective designs of therapeutic trials. In trials for mania, fewer sites may limit placebo response and enhance drug-placebo contrasts.

The therapeutic misconception and our models of competency and informed consent

The doctrine of informed consent rests on empirical claims. This is true particularly of what commentators have characterized as the "strong" model of informed consent. This model assumes that if adequate information is given to a competent individual, understanding will result and, permitted to make a voluntary decision, the individual will make a rational decision. However, the "therapeutic misconception" posits that individuals may confuse the goals of research with those of treatment and may make decisions that do not rest on adequate understanding. This article reviews research suggesting that this may in fact be true, and concludes that, as a result, traditional notions of informed consent may not yield results consistent with the assumptions on which the doctrine of informed consent rests.

A systematic review of antidepressant placebo-controlled trials for geriatric depression: limitations of current data and directions for the future

Depression in the elderly is a major public health problem as untreated depression adversely impacts comorbid illnesses. It is important to develop safe and effective antidepressant therapies for older individuals. We performed a systematic review of all published randomized, placebo-controlled antidepressant medication trials in populations over age 55 years. Papers were obtained via MEDLINE (1966-August 2003) and PSYCINFO (1872-August 2003). Unpublished trials, trials examining nonpharmacologic interventions, and papers reporting post hoc analyses were not included in this review unless they provided new insights. A total of 18 placebo-controlled trials examining acute efficacy met our criteria. The combined sample size in these studies was 2252. The mean sample size was 51 (range 20-728) and mean trial duration was 7 weeks. A total of 12 trials examined tricyclic antidepressants (TCAs), five trials examined selective serotonin reuptake inhibitors (SSRIs), two trials examined bupropion, and one trial examined mirtazapine. There were no published trials of venlafaxine or nefazodone. In all, 71.5% of trials reported significantly greater efficacy with drug than placebo. In conclusions, there is a paucity of published controlled antidepressant trials in the elderly. Most published studies examine small sample sizes and do not include common comorbid conditions. Efficacy studies examining relapse prevention are lacking. Large placebo response rates, lack of controlled head to head comparisons, and other methodological design differences make crosstrial comparisons difficult. Large simple studies are urgently needed to address the unmet needs for data on safety and efficacy of antidepressants in this population.

Therapeutic misconception and the appreciation of risks in clinical trials

Studies repeatedly have shown that clinical research subjects have trouble appreciating the implications for their clinical care of participating in a clinical trial. When this failure is based on a lack of appreciation of the impact on individualized clinical care of elements of the research design, it has been called the "therapeutic misconception". Failure to distinguish the consequences of research participation from receiving ordinary treatment may seriously undermine the informed consent of research subjects. This article reports results concerning appreciation of the risks of trial participation from intensive interviews with 155 subjects from 40 different clinical trials at two different medical centers in the USA. Working from transcripts of the interviews, every statement of a risk or disadvantage of trial participation was identified and coded into one of 5 different categories. Totally, 23.9% of subjects reported no risks or disadvantages in spite of being explicitly asked about them. Another 2.6% reported only incidental disadvantages such as having to drive a long way to get to the experimental site. In all 14.2% reported only disadvantages associated with the standard treatment (usually side effects). Another 45.8% told the interviewer about disadvantages and risks associated with the experimental intervention (usually side effects). Only 13.5% could report any risks or disadvantages resulting from the research design itself, such as randomization, placebos, double-blind designs and restrictive protocols. The results of this research suggest that subjects often sign consents to participate in clinical trials with only the most modest appreciation of the risks and disadvantages of participation.

The development, evolution and philosophy of a clinical research unit

OBJECTIVE

To describe the development,evolution and philosophy of a clinical research unit.

METHOD

The 20-year history of clinical psychiatric research in Christchurch is described. The variety of influences which have impacted upon the studies undertaken is acknowledged,as are the personal histories of key staff.

CONCLUSIONS

Clinical research is potentially endangered. The maintenance and development of clinical research requires a mix of individual inquisitiveness and determination,local opportunity and political will. Despite a political desire for evidence-based medicine; most political policies and practices impede the development of new knowledge and the collection of new evidence.

A curriculum for teaching psychiatric research bioethics

Psychiatric research has received intense ethical scrutiny during the past decade. Changes in how studies are designed, reviewed by ethics boards, conducted, and reported in the literature have created a need for a systematic approach to teaching psychiatric research ethics to clinical researchers in training. The purpose of this article is to describe a model curriculum and comprehensive background reading list for training in psychiatric research bioethics. The curriculum was designed as an interactive seminar in a research fellowship program but can be adapted and incorporated into existing medical school and psychiatry residency training curricula. Participants in the seminar provide formal and informal evaluations of each session and the seminar as a whole. The seminar, now in it's third year, has been regularly attended and highly regarded by the NIMH research fellows who have participated. In response to recommendations by the participants, the content and organization of the seminar has been modified. Clinical research is both scientifically and ethically complex. Our initial experience with a formal curriculum in psychiatric research bioethics suggests that this educational activity has been both meaningful and relevant for psychiatrists training to be clinical investigators.

Ethical issues in research and innovative therapy in children with mood disorders

Research involving children with mood disorders should generally offer a reasonable prospect of benefit to those involved, unless the risks are minimal. While federal regulations require a prospect of direct benefit, from an ethical perspective indirect benefits, such as the advantages of being in a clinical trial, are relevant. Standard care should not be presumed to be preferable to treatment in the context of a clinical trial, particularly if it has not been evaluated in well designed studies involving groups comparable to the patient. Similarly, active treatments in a controlled trial should not be presumed to be preferable to placebos, particularly in studies involving mood disorders where the placebo effect is more likely to be substantial. Innovative therapy-using approved drugs for unapproved purposes-may be more problematic than research, on theoretical and empirical grounds. Studies with no prospect of direct benefit and more than minimal risk are problematic when the patient is incompetent to provide meaningful consent. Whether or not a controlled trial involving children with mood disorders can be ethically justified depends on several factors, including the validity of standard treatment, the seriousness of the disorder, the likelihood of adverse consequences if treatment is delayed, the burden of the proposed intervention, and value judgments by parents, working collaboratively with a caring physician.