Coercion in Same-Day Research Consent

Voluntariness of Same-Day Consent for Participation in Low-Risk Clinical Anesthesia Research Trials: A Prospective, Randomized Trial

As a result of their unique practice patterns, many specialist physicians typically only meet patients on the date of an intervention such as surgery. However, some of the world's most prestigious academic centers do not allow research participants to be recruited on the same day as surgery. This is because of concerns, shared by researchers and research ethics boards, that patients may be too anxious or rushed to provide informed, voluntary consent immediately before an operation. This is not supported by evidence, and leads to potential inequities by restricting patients' opportunities to contribute to and benefit from research. The investigators undertook a randomized controlled trial incorporating deception to study the voluntariness of research consent provided by patients invited to enroll in a fabricated anesthesia research study at Women's College Hospital in Toronto, Ontario, Canada. Patients undergoing day surgery were randomized to receive research recruitment opportunities either days before surgery in the pre-operative assessment clinic, or on the surgical date. Post-operatively, patient's perceptions of undue influence or coercion in the consent process were examined with questionnaires and compared between these groups. This trial will help to design future perioperative studies, and will answer the important question of whether truly voluntary and informed same-day consent can be provided for participation in perioperative research.

Study Overview

• Status: Completed
• Conditions: Consent of Patients; Coercion to Participate in Research
• Intervention / Treatment: Other: Invitation to Consent to Trial Participation

• Study Type: Interventional
• Enrollment (Actual): 114
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5S 1B2
      • Women's College Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patient scheduled to undergo ambulatory anterior cruciate ligament repair under general anesthesia with an adductor canal nerve block at Women's Colege Hospital
• Age ≥18

Exclusion Criteria:

• Inability to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Advance Consent; Patients in this group were presented with the opportunity for trial participation in advance of surgery, during preoperative assessment approximately one week prior in the Pre-Anesthesia Clinic. Recruitment took place via telephone during this pre-operative assessment, and followed all standard procedures for trial recruitment at Women's College Hospital.	Other: Invitation to Consent to Trial Participation; In this trial, the intervention being studied was the timing of an invitation to participate in a fabricated low-risk clinical anesthesia research trial. Patients were recruited into this fictitious trial either several days in advance of surgery, or on the day of surgery, and post-operative evaluations aimed to measure whether these groups experienced different degrees of coercion or voluntariness in their decisions to participate.
Experimental: Day of Surgery Consent; Patients in this group were presented with the opportunity for trial participation on the day of surgery, immediately before proceeding to their operation at Women's College Hospital. Recruitment took place in person at the bedside, and otherwise followed all standard procedures for trial recruitment at Women's College Hospital.	Other: Invitation to Consent to Trial Participation; In this trial, the intervention being studied was the timing of an invitation to participate in a fabricated low-risk clinical anesthesia research trial. Patients were recruited into this fictitious trial either several days in advance of surgery, or on the day of surgery, and post-operative evaluations aimed to measure whether these groups experienced different degrees of coercion or voluntariness in their decisions to participate.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Average score on combined modified coercion scales	Minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion.	Measured on postoperative day one.
Average Score on modified Iowa Coercion Questionnaire	Minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion.	Measured on postoperative day one.
Average Score on Modified Coercion Assessment Scale	Minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion.	Measured on postoperative day one.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of enrollment into the fictitious trial		Measured when patients were approached with an invitation to participate in the trial. For patients in the Advance Consent Group this was, on average, preoperative day seven. For patients in the Day of Surgery Group this was postoperative day zero.
Responses to individual items on the combined modified coercion scales	Each item has a minimum score of 1 and maximum score of 4, with higher scores corresponding to a greater degree of coercion.	Measured on postoperative day one.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Association between participant sex and average score on combined modified coercion scales	This secondary analysis uses linear regression to test for statistical dependence between participant sex (categorical variable self-reported on the postoperative questionnaire) and average score on the combined modified coercion scales (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant sex and average score on the modified Iowa Coercion Questionnaire	This secondary analysis uses linear regression to test for statistical dependence between participant sex (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Iowa Coercion Questionnaire (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant sex and average score on the modified Coercion Assessment Scale	This secondary analysis uses linear regression to test for statistical dependence between participant sex (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Coercion Assessment Scale (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant age and average score on combined modified coercion scales	This secondary analysis uses linear regression to test for statistical dependence between participant age (continuous variable self-reported on the postoperative questionnaire) and average score on the combined modified coercion scales (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant age and average score on the modified Iowa Coercion Questionnaire	This secondary analysis uses linear regression to test for statistical dependence between participant age (continuous variable self-reported on the postoperative questionnaire) and average score on the modified Iowa Coercion Questionnaire (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant age and average score on the modified Coercion Assessment Scale	This secondary analysis uses linear regression to test for statistical dependence between participant age (continuous variable self-reported on the postoperative questionnaire) and average score on the modified Coercion Assessment Scale (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant education and average score on combined modified coercion scales	This secondary analysis uses linear regression to test for statistical dependence between participant total years of education (continuous variable self-reported on the postoperative questionnaire) and average score on the combined modified coercion scales (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant education and average score on the modified Iowa Coercion Questionnaire	This secondary analysis uses linear regression to test for statistical dependence between participant total years of education (continuous variable self-reported on the postoperative questionnaire) and average score on the modified Iowa Coercion Questionnaire (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant education and average score on the modified Coercion Assessment Scale	This secondary analysis uses linear regression to test for statistical dependence between participant total years of education (continuous variable self-reported on the postoperative questionnaire) and average score on the modified Coercion Assessment Scale (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant country of upbringing and average score on combined modified coercion scales	This secondary analysis uses linear regression to test for statistical dependence between participant country of upbringing (categorical variable self-reported on the postoperative questionnaire) and average score on the combined modified coercion scales (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant country of upbringing and average score on the modified Iowa Coercion Questionnaire	This secondary analysis uses linear regression to test for statistical dependence between participant country of upbringing (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Iowa Coercion Questionnaire (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant country of upbringing and average score on the modified Coercion Assessment Scale	This secondary analysis uses linear regression to test for statistical dependence between participant country of upbringing (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Coercion Assessment Scale (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant minority status and average score on combined modified coercion scales	This secondary analysis uses linear regression to test for statistical dependence between participant minority status (categorical variable self-reported on the postoperative questionnaire) and average score on the combined modified coercion scales (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant minority status and average score on the modified Iowa Coercion Questionnaire	This secondary analysis uses linear regression to test for statistical dependence between participant minority status (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Iowa Coercion Questionnaire (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.
Association between participant minority status and average score on the modified Coercion Assessment Scale	This secondary analysis uses linear regression to test for statistical dependence between participant minority status (categorical variable self-reported on the postoperative questionnaire) and average score on the modified Coercion Assessment Scale (minimum average score of 1 and maximum average score of 4, with higher scores corresponding to a greater degree of coercion).	Measured on postoperative day one.

Collaborators and Investigators

• Sponsor: University of Toronto
• Collaborators: Women's College Hospital; Toronto Metropolitan University
• Investigators: Principal Investigator: Richard Brull, MD, FRCPC, University of Toronto

Publications and helpful links

General Publications

• Brenna CTA, Walton N, Cohn M, Siddiqui U, Huszti E, Brull R. Coerced consent in clinical research: study protocol for a randomized controlled trial. Trials. 2024 Jul 4;25(1):452. doi: 10.1186/s13063-024-08294-4.

Helpful Links

• Initial trial registration published under embargo

Study record dates

Study Major Dates

• Study Start (Actual): June 4, 2024
• Primary Completion (Actual): June 3, 2025
• Study Completion (Actual): June 6, 2025

Study Registration Dates

• First Submitted: January 16, 2026
• First Submitted That Met QC Criteria: January 23, 2026
• First Posted (Actual): February 2, 2026

Study Record Updates

• Last Update Posted (Actual): February 2, 2026
• Last Update Submitted That Met QC Criteria: January 23, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Clinical trials; Coercion; Voluntariness; Research consent; Perioperative research
• Other Study ID Numbers: 2023-0007-E; 46twc (Other Identifier: Open Science Framework)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Deidentified, aggregate trial data supporting the findings of this study will be made available upon reasonable request to the corresponding author after publication.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No