Cochrane Evidence Updates - Information interventions for orienting patients and their carers to cancer care facilities (including professional commentaries)

AUTHORS' CONCLUSIONS:
This review has demonstrated the feasibility and some potential benefits of orientation interventions. There was a low level of evidence suggesting that orientation interventions can reduce distress in patients. However, most of the other outcomes remain inconclusive (patient knowledge recall/ satisfaction). The majority of studies were subject to high risk of bias, and were likely to be insufficiently powered. Further well conducted and powered RCTs are required to provide evidence for determining the most appropriate intensity, nature, mode and resources for such interventions. Patient and carer-focused outcomes should be included.

JAMA -- Letter: bias and trials stoped for early benefit (5)

Letters
Bias and Trials Stopped Early for Benefit

Scott M. Berry; Bradley P. Carlin; Jason Connor
JAMA 2010; 304: 156. [Extract] [Full text] [PDF]

Letters
Bias and Trials Stopped Early for Benefit

Edward L. Korn; Boris Freidlin; Margaret Mooney
JAMA 2010; 304: 157-a-158-a. [Extract] [Full text] [PDF]

Letters
Bias and Trials Stopped Early for Benefit

Steven Goodman; Donald Berry; Janet Wittes
JAMA 2010; 304: 157. [Extract] [Full text] [PDF]

Letters
Bias and Trials Stopped Early for Benefit—Reply

Gordon H. Guyatt; Dirk Bassler; Victor M. Montori
JAMA 2010; 304: 158-a-159-a. [Extract] [Full text] [PDF]

Letters
Bias and Trials Stopped Early for Benefit

Susan S. Ellenberg; David L. DeMets; Thomas R. Fleming
JAMA 2010; 304: 158. [Extract] [Full text] [PDF]

Abstract/full text - Reporting bias in medical research - a narrative review

Review
Reporting bias in medical research - a narrative review
Published: 13 April 2010
Abstract (provisional) (click on pdf for full access)

Reporting bias represents a major problem in the assessment of health care interventions. Several prominent cases have been described in the literature, for example, in the reporting of trials of antidepressants, Class I anti-arrhythmic drugs, and selective COX-2 inhibitors. The aim of this narrative review is to gain an overview of reporting bias in the medical literature, focussing on publication bias and selective outcome reporting. We explore whether these types of bias have been shown in areas beyond the well-known cases noted above, in order to gain an impression of how widespread the problem is. For this purpose, we screened relevant articles on reporting bias that had previously been obtained by the German Institute for Quality and Efficiency in Health Care in the context of its health technology assessment reports and other research work, together with the reference lists of these articles. We identified reporting bias in 40 indications comprising around 50 different pharmacological, surgical (e.g. vacuum-assisted closure therapy), diagnostic (e.g. ultrasound), and preventive (e.g. cancer vaccines) interventions. Regarding pharmacological interventions, cases of reporting bias were, for example, identified in the treatment of the following conditions: depression, bipolar disorder, schizophrenia, anxiety disorder, attention-deficit hyperactivity disorder, Alzheimer's disease, pain, migraine, cardiovascular disease, gastric ulcers, irritable bowel syndrome, urinary incontinence, atopic dermatitis, diabetes mellitus type 2, hypercholesterolaemia, thyroid disorders, menopausal symptoms, various types of cancer (e.g. ovarian cancer and melanoma), various types of infections (e.g. HIV, influenza and Hepatitis B), and acute trauma. Many cases involved the withholding of study data by manufacturers and regulatory agencies or the active attempt by manufacturers to suppress publication. The ascertained effects of reporting bias included the overestimation of efficacy and the underestimation of safety risks of interventions.  
In conclusion, reporting bias is a widespread phenomenon in the medical literature.
Mandatory prospective registration of trials and public access to study data via results databases need to be introduced on a worldwide scale. This will allow for an independent review of research data, help fulfil ethical obligations towards patients, and ensure a basis for fully-informed decision making in the health care system.

PLoS ONE: Bias Due to Changes in Specified Outcomes during the Systematic Review Process