Related Experiment Video
Updated: Jul 7, 2026
Electroencephalography Network Indices as Biomarkers of Upper Limb Impairment in Chronic Stroke
Published on: July 14, 2023
Assessing the impact of the requirement for explicit consent in a hospital-based stroke study
C Jackson1, L Crossland, M Dennis
1Division of Clinical Neurosciences, University of Edinburgh, Bramwell Dott Building, Western General Hospital, Edinburgh, EH4 2XU, UK.
Insights
Explicit consent requirements for clinical research reduce participation and introduce bias. An opt-out system for minimally invasive studies can minimize bias and costs, improving the quality of epidemiological research.
Area of Science:
- Clinical Epidemiology
- Medical Research Ethics
Background:
- Increasing regulations, including explicit consent, may negatively impact clinical epidemiological research quantity and quality.
- The study addresses potential biases introduced by explicit consent requirements in medical research.
Purpose of the Study:
- To evaluate the biases associated with explicit consent in a hospital-based stroke research register.
- To compare participation and characteristics between consented and non-consented stroke patients.
Main Methods:
- Compared patients in a stroke research register (requiring explicit consent) with those in a concurrent clinical stroke audit (no explicit consent).
- Analyzed numbers of consenters, refusers, and those not approached due to logistical reasons.
- Compared baseline characteristics of participants versus non-participants.
Main Results:
- Out of 1228 stroke audit patients, 1075 (88%) were in the research register, with higher outpatient participation.
- Only 1% of eligible patients refused involvement; most non-participation was due to inability to seek consent.
- Significant baseline characteristic differences between participants and non-participants were observed, potentially affecting outcomes.
Conclusions:
- Explicit consent reduced participation and introduced bias in the stroke research register.
- An opt-out system for minimally intrusive epidemiological studies could minimize bias and reduce costs.
- Revising consent procedures is crucial for enhancing the quality and efficiency of clinical research.
Background:
Increasing regulation of medical research, in particular the requirement for explicit consent, may reduce the quantity and quality of clinical epidemiological research.
Aim:
To assess the potential biases arising from the need for explicit consent in our hospital-based stroke research register.
Design:
Comparison of patients enrolled into our stroke research register with those included in a concurrent clinical stroke audit that targeted the same population but did not require explicit consent.
Methods:
We obtained the numbers of consenters, refusers and those from whom consent was not sought for various logistical reasons. We compared characteristics of participants (those eventually included in the research register) vs. non-participants.
Results:
Of 1228 patients included in the stroke audit during an 18-month period, 1075 (88%) were also included in the research register, with higher participation among outpatients than inpatients. Only 1% of eligible patients refused involvement in any aspect of the research register. By far the largest number of non-participants was those from whom we could not seek consent for practical reasons. Comparison of baseline characteristics showed important differences between participants and non-participants that could affect outcome.
Conclusion:
Very few patients refused inclusion in our research register, but the need for explicit consent reduced participation and introduced bias. An opt-out system avoiding the need for explicit patient consent for minimally intrusive clinical epidemiological studies would minimize bias and reduce the considerable time and costs associated with the consent process.
