Consent in resuscitation trials: Benefit or harm for patients and society?

Context: Research in an emergency setting is challenging because there may not be sufficient opportunity or time to obtain informed consent from the patient or their Legally authorized representative. Such research can be conducted without prior consent if specific criteria are met. However consent is sometimes required for continued participation and may bias the results of the study. Objective: To review regulations related to waiver of consent in emergency research, and evidence of whether such regulations introduce bias. Results: Emergency research can be conducted without consent, either through community disclosure and consultation followed by patient or family notification and consent for continued participation after the intervention was applied, or under a minimal risk waiver. Review of the clinical record is necessary to determine important outcomes such as survival to discharge. If consent is required for this review but not granted, then these data are missing during analysis. If seriously ill or disadvantaged patients are less likely to assent, then investigators cannot determine reliably whether these vulnerable patients were harmed by the intervention. If missing data are different from complete data, then the analysis is susceptible to bias, and the conclusions could be misleading. Extrapolation from non-consent rates in resuscitation studies to results from the DAVID trial demonstrates that the rate of absence of data and information due to lack of assent can influence whether there is a significant difference between treatment groups (survival of control versus intervention: p = 0.04 for complete data; p = 0.08 for 10.8% lack of assent; p = 0.40 for 19.7% lack of assent). Conclusions: Exception from consent for emergency research should extend to review of the hospital record as the standard in emergency research. The only potential risk to patients associated with review of the clinical record after the intervention is loss of privacy and confidentiality. Appropriate safeguards can be taken to minimize this risk. (c) 2006 Elsevier Ireland Ltd. All rights reserved.