Predictors of the Level of Shared Decision Making in Vascular Surgery: A Cross Sectional Study

Objective: Although patients with vascular diseases often face multiple treatment options with different risks and benefits, the application of shared decision making (SDM) remains low. In SDM, clinicians and their patients work together to decide upon the treatment option that best fits the patient's situation and preference. This study aimed to reveal predictors of the extent to which the SDM process occurs in vascular surgery. Methods: This was a cross sectional cohort substudy of the OVIDIUS trial, a multicentre, randomised, stepped wedge trial on the effect of implementing SDM supporting tools. The data of outpatients visiting university and general hospitals and suffering from abdominal aortic aneurysms (AAAs), intermittent claudication (IC), or varicose veins (VV) were used. Consultations were audio recorded. SDM levels were scored independently by two evaluators, using the OPTION-5 instrument, on a scale from 0% (no SDM effort) to 100% (exemplary SDM effort). Possible associations between the OPTION-5 scores and patient, clinician, and consultation characteristics were investigated using multivariable linear regression analysis. Results: Of the 342 patients included (AAA, n = 87; VV, n = 143; IC, n = 112), 60% were male and mean age was 64 years. Overall, the SDM score was relatively low; mean +/- SD 33.8% +/- 13.2%, mainly due to insufficient support for the patient in deliberating their options. Regression analysis showed that the mean SDM scores in consultation with patients with IC and patients with VV were -9.9 (95% confidence interval [CI] -13.2 - - 6.5; p < .001) and -12.7 (95% CI -17.3 - -8.0; p < .001) points lower than in patients with AAA, respectively. Consultations by a resident in training or nurse practitioner resulted in a -8.6 (95% CI -13.1 - - 4.0; p < .001) and -4.2 (95% CI -7.9 - -0.42; p = .029) point lower SDM score than by a surgeon, respectively. A consultation longer than 30 minutes resulted in a 5.8 (95% CI 1.3 - 10.3; p = .011) point higher SDM score than consultations lasting fewer than 10 minutes. Conclusion: In this study, it was found that SDM can still be improved, especially by helping patients understand and deliberate about their options. Spending time weighing up the options, notably with patients with IC and VV, will help improve the SDM process. Training in SDM consultations is important, particularly for junior clinicians.