Stephen Polgar

Ethics, methodology and the use of placebo controls in surgical trials

There is an emergent view among North American researchers and bioethicists that not only is the use of sham surgery ethical, but that it should also be mandatory when conducting trials to evaluate surgical procedures such as neural grafting. This view is based on erroneous assumptions concerning the magnitude of the placebo effects associated with surgery. A detailed analysis of four recent clinical trials failed to provide consistent evidence for pronounced and long term improvements in sham operated patients. There was no evidence that the results of the placebo control groups were necessary for identifying unsafe and ineffectual surgical procedures. We contend that the advancement of clinical science and the protection of individual patients are best guaranteed by adopting the principles of evidence-based medicine.

Implications of Neurological Rehabilitation for Advancing Intracerebral Transplantation

Neurological rehabilitation involves the systematic presentation of environmental stimuli and challenges that enable the patient to learn strategies for minimizing their disabilities. Rehabilitation therapy of transplant recipients may be an important factor in enhancing the efficacy of the transplanted organ or tissue to promote functional recovery. Laboratory research and clinical trials on neural transplantation, as an experimental treatment for neurological disorders (e.g., Parkinsons disease, Huntingtons disease, and cerebral ischemia), have focused primarily on devising effective surgical implantation strategies with little attention devoted to the interaction between environmental factors and restorative neurosurgery. Exercise training as part of neurological rehabilitation may be an important factor for neural transplantation therapy for Parkinsons disease. Rehabilitation providers are particularly well placed to provide the environment and the support to optimize the behavioral functioning of neural transplant patients in learning to use the new grafted tissue.

Paradigm collapse in psychology: The necessity for a “two methods” approach

In the last two decades much effort in mainstream applied psychology has been invested in the change of fashion from behavioural to cognitive-behavioural, and in incursions into new fields such as health. This activity has distracted researchers and practitioners from the task of addressing and resolving contradictions that have become embedded in the production of the discipline. There has been a pretence of continuous advancement while in reality the behavioural paradigm has collapsed and has not been replaced by an acceptable alternative. Urgent attention must be given to the resolution of these pervasive conceptual problems. It is the contention of this paper that the production of a well-formed and applicable discipline requires detailed understanding and explicit utilisation of both positivist and interpretative methodologies.

A critical analysis of evidence for using sham surgery in Parkinson's disease: implications for public health

Sham surgery was introduced as a means for improving the methodological quality of surgical research and evaluation. The development of cellular‐based surgical therapies for the treatment of Parkinsons disease provides an opportunity to carefully analyse the alleged methodological benefits of sham surgery. However, detailed analysis of the evidence does not support these hypothesised advantages. In this paper, we argue that sham surgery is a public health concern as vulnerable individuals are exposed to unnecessary and costly surgical procedures that have no benefits for ensuring rigorous health research.

Stem Cell Therapy for Parkinson's disease: Are Double-Blind Randomized Control Trials the Best Design for Quantifying Therapy Outcomes?

Randomized controlled trials [RCTs] are recognized as the most rigorous method for evaluating the safety and efficacy of novel interventions. The fact that a series of RCTs evaluating cellular therapies for Parkinson’s disease [PD] resulted in negative outcomes has delayed the translation of stem cell research into viable treatments for people with brain damage. At present, there are a variety of strategies being followed to improve outcomes for cellular therapies, including reassessment of the theory and methodology guiding the research program. In this position paper we present an argument based on empirical and theoretical grounds that the use of double-blind, placebo controlled trials are not the best approach for testing the efficacy of cellular therapies for PD. Evidence includes the highly variable effects of neural grafts found in double blind RCTs in comparison to the much larger benefits in open-label trials for people with PD in double-blind RCT. We suggest that the ambiguity and confusion created about the actual nature of the treatment in the context of a double-blind trial compromises the efforts of participants and their Carers to make the best therapeutic use of the grafted cells. The theoretical grounds for rejecting the use of double-bind RCTs is based on the Composite Brain Theory, which postulates that to insure optimal therapeutic outcomes it is essential to integrate the intracerebral grafting of cells with an active program of neurorehabilitation. We are recommending the use of pragmatic RCTs which involve the comparison of cellular transplantation and rehabilitation with best practice pharmacotherapy or Deep Brain Stimulation as comparison groups. Using a pragmatic trial design will ensure optimal outcomes for each of the treatment groups and produce evidence applicable for identifying best available treatments for people with PD.

Evidence-Based Methodology for Advancing Neural Reconstruction

The purpose of this chapter is to identify recent developments in health research methodology that might be useful for ensuring progress in cellular therapy for brain repair. Recently, commentators suggested that the need for rapid scientific and commercial successes has privileged approaches, which are inadequate for solving the problems inherent in the project of repairing the human brain. Critical analysis of recent clinical trials for the treatment of Parkinson’s disease (PD) revealed a number of unresolved conceptual and methodological issues. These issues included: a lack of consensus concerning treatment goals, the absence of clearly defined effect sizes for clinical significance, and the weak communication of research findings for the accurate synthesis of evidence. A particular problem has been the lack of interest in collecting qualitative data regarding the experiences and values of patients participating in the research. It is recommended that the explicit adoption of so-called “evidence-based” approaches to research design, data collection, and analysis will ensure optimal outcomes for using stem cells for cellar therapies.

A Critical Evaluation of the Methodological Obstacles to Translating Cell-Based Research Into an Effective Treatment for People With Parkinson’s Disease

The remarkable scientific and technological advances in the field of cell research have not been translated into viable restorative therapies for brain disorders. In this article, we examine the best available evidence for the clinical efficacy of reconstructive intracerebral transplantation in people with Parkinson’s disease (PD), with the aim of identifying methodological obstacles to the translation process. The major stumbling block is the fact that the potential contributions of people with neural grafts and the effects of the physical and social environment in which they recover have not been adequately investigated and applied to advancing the clinical stages of the research program. We suggest that the biopsychosocial model along with emerging evidence of targeted rehabilitation can provide a useful framework for conducting research and evaluation that will ensure the best possible outcomes following intracerebral transplantation for PD.

The politics of error: A reply to dyck

Abstract The principal thesis of McGartland and Polgar (1994) is that for mainstream psychology to be a coherent and applicable discipline it needs to include, in a formal way, both positivist and interpretive methodologies and the data produced by them. In his comments on this article Dyck (1994) has demonstrated a failure to understand the nature of the relationship between positivist and interpretative methodologies, and has misrepresented the arguments used in exemplars to illustrate and support the above thesis. The point ignored by Dyck is that interpretive analyses of subjectivity and interactions in particular social contexts, such as when analysing the “errors” in the present debate, contain a richness of information that is unavailable when viewing the same events from an exclusively positivist perspective.