A feasibility study to test if an intervention can improve shared decision-making in advanced Parkinson's disease

In advanced stages of Parkinson’s disease (PD), patients and neurologists regularly face complex treatment decisions. Shared decision-making (SDM) can support the process where evidence, the clinician’s expertise and the patient’s preferences jointly contribute to reach an optimal decision.

The aim of the study is to test the feasibility of the SDM intervention by (1) analysing the acceptability of the intervention by users (i.e. professionals and patients); (2) assessing the level of implementation; (3) testing efficacy on a small-scale; and (4) evaluating the study procedures.



Using an uncontrolled before-after mixed methods design, patients in the pre-intervention group will receive information and decisional support as usual. Patients in the post-intervention group will receive the SDM intervention, consisting of an Option Grid TM patient decision aid and a website with supplementary information plus a value clarification tool for both patients and professionals. An Option Grid is a one-page, evidence-based summary of available options, listing the frequently asked questions that patients consider when making treatment decisions. A value clarification tool helps patients identify which option he/she prefers based on attributes in the treatment decision context. Neurologists and PD nurse specialists will receive a 1-hour instruction on SDM and how to use the SDM intervention.

Through purposive sampling, neurologists and PD nurse specialists will be recruited from both specialised neurology clinics and community-based hospitals. Included professionals will invite consecutive patients who are eligible for the advanced therapies.

Data will be collected using questionnaires, interviews, audio observations of the consultations, and tracking users’ logging behaviour of the website. Data will be analysed using a mixed methods design.



The mixed methods design will create a deeper understanding of how the SDM intervention affects the interactions between professionals (neurologist and/ or PD nurse specialist) and the patient, when an advanced treatment is chosen. The results of the study will inform the design of an RCT to test the effectiveness of the SDM intervention.

The study will address the feasibility of the shared decision-making (SDM) intervention by (1) analysing the acceptability of the intervention by users (i.e. professionals and patients); (2) assessing the level of implementation; (3) testing efficacy on a small-scale; and (4) evaluating the study procedures.

Demographic data professionals and patients: at moment of inclusion

acceptability: at end of post-intervention phase with patients from intervention group and professionals

level of implementation: continuous from the introduction of the intervention to the end of the post-intervention phase

Small scale efficacy testing, level of SDM: during the decision-making process in both the pre-intervention phase and the post-intervention phase

Small scale efficacy testing, decision quality: at time of inclusion of the patients and at the end of the decision process in both the pre-intervention phase and post-intervention phase

feasibility of study procedures: throughout the study

contextual factors: throughout the study

It is a before- after design.

For the pre-intervention group, patients will receive information and decision support as usual. The decision process of an individual patient ends when a preliminary choice for a treatment has been made and the screening for definite treatment eligibility is initiated.



Once 20 patients in the pre-intervention group have finished their decision process, the professionals will be introduced to the shared decision-making (SDM) intervention.

The SDM intervention consists of an Option Grid, online supplementary information with a value clarification tool and a one-hour training for professionals. An Option Grid is a one-page, evidence-based summary of available options presented in a tabulated format, listing the frequently asked questions (FAQs) that patients consider when making treatment decisions. An Option Grid is used in the clinical encounters and stimulates the discussion on the treatment options. A value clarification tool helps patients think about which attributes of options matters to him/ her most in order to identify which option he/she prefers.



After the introduction of the intervention to the professionals, the 20 patients for the post-intervention group will be included and enter the decision process using the SDM intervention