Skip to main content

Table 2 Agreement between patients and surrogates for hypothetical stroke scenarios

From: The accuracy of surrogate decision makers: informed consent in hypothetical acute stroke scenarios

Scenario 1: TPA vs. no treatment Scenario 2: TPA vs. clot removal procedure Scenario 3: TPA vs. standard RCT Scenario 4: TPA vs. adaptive RCT
  Patients   Patients   Patients   Patients
Proxies Would you want TPA? Yes No Proxies Would you want the procedure? Yes No Proxies Would you want the trial? Yes No Proxies Would you want the trial? Yes No
Yes 95.5% (n = 191) 2% (n = 4) Yes 1% (n = 2) 4.5% (n = 9) Yes 4.5% (n = 9) 9% (n = 18) Yes 28.5% (n = 57) 21.5% (n = 43)
No 2% (n = 4) 0.5% (n = 1) No 8.5% (n = 17) 86% (n = 172) No 17% (n = 34) 69.5% (n = 139) No 29.5% (n = 59) 20.5% (n = 41)
  Mean SD   Mean SD   Mean SD   Mean SD
Patient confidence 8.0 2.1 Patient confidence 8.1 2 Patient confidence 8.0 1.9 Patient confidence 7.8 1.9
Proxy confidence 8.5 1.7 Proxy confidence 8.5 1.9 Proxy confidence 8.4 1.9 Proxy confidence 8.0 1.9
Proxy certainty 8.4 1.9 Proxy certainty 8.0 2.2 Proxy certainty 7.8 2.3 Proxy certainty 7.5 2.1
Cohen’s Kappa statistic 0.18 Cohen’s Kappa statistic 0.07 Cohen’s Kappa statistic 0.11 Cohen’s Kappa statistic -0.02
AC1 (95% CI) 0.96 (0.93-0.99) AC1 (95% CI) 0.87 (0.79-0.91) AC1 (95% CI) 0.63 (0.53-0.74) AC1 (95% CI) -0.01 (-0.13 – 0.13)
  1. Overall agreement is observed in the bolded diagonal cells (i.e for scenario 1: 96% of patients and proxies agreed). Counts and proportions listed for all scenarios. Patient and surrogate confidence was measured on a 10 point Likert scale. SD = standard deviation. tPA = tissue plasminogen activator. RCT = Randomized controlled trial. AC1 = Gwet’s agreement coefficient. CI = confidence interval.