Samenvatting studieopzet


Rationale: Most patients with non-medullary thyroid carcinoma face a number of treatment choices. For these patients, current guidelines state that less aggressive treatment (e.g. hemi-thyroidectomy vs. total thyroidectomy and postponing tyrosine kinase inhibitors (TKI) treatment) is acceptable leaving room for patients’ preferences. Care should honour preferences and values of individual patients and shared decision making (SDM) can help. The principle of SDM is twofold: 1. physicians provide patients with information on the existing options, and 2. help patients identify their preferences considering their individual values and needs.

Addressing patients’ treatment-related values is arguably the most difficult part of SDM so patient values are less likely to be discussed and honoured in a consultation. Current tools are clearly insufficient and tools should be integrated and applied in consultations to increase effectiveness.


Objective: to develop, implement and evaluate a combination of tools to improve SDM during the treatment trajectory of thyroid carcinoma (TC) patients in situations when clear cut recommendations cannot be made, and to make physicians more aware of patients’ values through SDM.


Study design: A clinical multicentre prospective randomised controlled trial with two arms, lasting about 1 month.


Study population: Patients with TC, either newly diagnosed or patients with advanced disease, presently in the follow-up at the participating centers will be included. During their care pathway, two treatment choices occur namely 1) the extent of thyroid resection, 2) the initiation of TKIs, covering the whole treatment trajectory of these patients.


Intervention: In the intervention arm, patients have COMBO, consisting of the decision aid, the SDM-booster, and the values deliberation training for physicians . In the control arm, patients have the values deliberation training for physicians alone.


Main study parameters/endpoints: The primary outcome is SDM. For both arms, the decision consultation is audio-recorded and SDM is measured with the OPTION5 scale. Physicians’ own values and substitute values are also noted. Patients’ post-consultation values and decision outcomes are assessed 1 week after the consultation by questionnaires sent at home.


Nature and extent of the burden and risks associated with participation, benefit and group relatedness: No negative effects are expected, neither for the decision aid, nor for the communication training for doctors. Patients face difficulties to express their values in the patient-doctor communication. Benefits: better knowledge, being more decisive, improves autonomy, self-management, and reduces regret, thus improving quality of life.