Using empirical data to inform the ethical evaluation of placebo controlled trials

Open-label use of placebos in the treatment of ADHD: a pilot study

BACKGROUND

This study examined short-term efficacy, side effects and acceptability of a placebo treatment procedure designed to maintain children with attention deficit hyperactivity disorder (ADHD) on 50% of their usual stimulant dose.

METHODS

An open-label prospective crossover trial was conducted in 26 children with ADHD, ages 7-15 years, stable on stimulant therapy, followed at a community-based developmental paediatrics ADHD clinic. Subjects were randomly assigned to one of two orders of experimental conditions: (1) baseline (100%) dose (1 week), then 50% dose (1 week), then 50% dose + placebo (1 week), or (2) baseline (100%), then 50% dose + placebo, then 50% dose. The inert nature of the placebo was fully disclosed to parent and child. Treatment was open-label for child, parents and physician, but single blind for teachers. Main outcome measures included weekly IOWA Conners parent and teacher rating scales, the Pittsburgh side effects rating scale (PSERS) and the Clinical Global Impressions (CGI) scale.

RESULTS

Parent IOWA showed ADHD behaviour tended to remain the same when the dose of stimulant medication was reduced with placebo but to deteriorate when the dose was reduced without placebo. There were no significant differences between conditions on the Teacher IOWA. PSERS scores were higher at baseline than on 50% dose. On the CGI, there was a significant difference (P = 0.004) between the 50% dose and the 50% + placebo conditions. Individual subject analysis showed that eight subjects met criteria for responder.

CONCLUSIONS

Results indicate that the open-label placebo treatment was acceptable and efficacious in the short term for some children.

Children's and parents' perspectives on open-label use of placebos in the treatment of ADHD

BACKGROUND

The purpose of this study was to examine the efficacy and acceptability of an open-label conditioned placebo dose reduction (CPDR) treatment in 70 children with attention deficit hyperactivity disorder (ADHD). This paper focuses on the qualitative data from the study.

METHODS

Following a double-blind, crossover dose finding procedure to determine each subject's optimal dose of stimulant medication, subjects were randomized to the CPDR treatment or one of two control groups. Outcome measures included parent and teacher ratings of ADHD behaviours and stimulant side effects. Qualitative assessments were based on open-ended interviews of children and parents. Positive responders to CPDR and controls were followed for 3 months to assess persistence of treatment benefits.

RESULTS

Children randomized to CPDR showed an excellent treatment response, well maintained over time. Parents and children were generally accepting of the treatment. Most parents reported treatment benefits and 80% of the children found the placebo to be useful. Full disclosure of the placebo to parents and children did not appear to negate the placebo's effectiveness. Participation effects and changes in caregiver behaviour may have contributed to positive treatment outcomes.

CONCLUSIONS

Open-label use of placebos as part of CPDR treatment may represent an innovative, ethical way of harnessing the power of placebos in clinical therapeutics.

A normative justification for distinguishing the ethics of clinical research from the ethics of medical care

In the research ethics literature, there is strong disagreement about the ethical acceptability of placebo-controlled trials, particularly when a tested therapy aims to alleviate a condition for which standard treatment exists. Recently, this disagreement has given rise to debate over the moral appropriateness of the principle of clinical equipoise for medical research. Underlying these debates are two fundamentally different visions of the moral obligations that investigators owe their subjects.

Some commentators and ethics documents claim that physicians, whether acting as care givers or researchers, have the same duty of beneficence towards their patients and subjects: namely, that they must provide optimal medical care. In discussing placebo surgery in research on refractory Parkinson's disease, Peter Clark succinctly states this view: “The researcher has an ethical responsibility to act in the best interest of subjects.”

Placebo effects in developmental disabilities: Implications for research and practice

Recent clinical trials of secretin in children with autism showed robust placebo effects and no benefit of secretin over placebo. This article explores the reasons for the observed placebo effects, focusing on the heightening of positive expectancy by media attention and by the sensory experiences associated with intravenous injections. Comparisons are drawn with research involving other novel treatments and other clinical populations of children with developmental disabilities and neurobehavioral disorders. Research regarding mechanisms of placebo effects is reviewed, including patient and clinician attributes, expectancy effects, participation effects, changes in caregiver behavior, and conditioning. New evidence regarding the biological basis of placebo effects is briefly presented. Since placebo effects are ubiquitous and may operate by a variety of mechanisms, research design is critical in designing clinical trials and in evaluating other outcomes research. Measurement issues important for research in developmental disabilities are emphasized. Ethical concerns have been raised regarding the use of placebo in clinical research, but current analysis suggests that placebo controls are necessary and defensible on ethical grounds, if certain conditions are met. The study of placebo effects ("placebology") holds great promise as a new area of research in therapeutics. The author's research in the potential augmentation of stimulant effects in children with attention deficit/hyperactivity disorder (ADHD) by adding placebo in open label is briefly presented. The placebo has always been integral to the practice of medicine, but advances in scientific medicine and medical ethics have diminished the role and use of placebo in practice. An innovative approach to the ethical use of placebo is proposed.

Placebo: its action and place in health research today--summary and conclusions

The material presented at this conference pointed to a new dimension in the prosecution of activities that seek to relieve people of disease. While the simple instrument of the placebo may show those interested in the efficacy of physiologically active chemicals the extent to which the chemical of interest is actually active, the surprising outcome of such studies is that the placebo per se is worthy of more general study. This, when taken further, points to the ways in which mind can influence the matter of the body. Of course, mind itself is an activity of matter, so we may retain the experimental approach that has told us about the world outside ourselves to examine the world that is inside our brains. New techniques and approaches to these once intractable problems are now in train. Where they will lead us we cannot predict, but as with the emergence of all new tools, we have to adopt those ethics that will carry us forward with the expectation that we will maximise benefits and minimise harms.