Background. Depression puts a great burden on both patients, relatives and society as a whole. Electroconvulsive therapy (ECT) is regarded as a safe and effective treatment for severe and chronic depressive episodes, even when other interventions such as psychotherapy or psychopharmacology have failed. Despite its superior efficacy, use of ECT for depressed patients is surprisingly low in most European countries as exemplified in a recent Dutch study. This low application rate is possibly due to (1) limited knowledge on the optimal position of ECT in the treatment algorithms, (2) a lack of knowledge on cost-effectiveness, (3) fear for (cognitive) side-effects in patients, relatives and professionals, and (4) the outdated representation of ECT in the media and society at large. Methods. The present study will overcome the aforementioned limitations and setup a large database of merged clinical and research cohorts of ECT-patients (N>1500) and an observational prospective cohort study, in order to analyze aspects of (cost-) effectiveness and side-effects of ECT in retro- and prospective Dutch data. Using these results and together with qualitative information from patients and their relatives, we will disseminate the gained knowledge and develop with a decision-making tool that will guide future patients and their family members referred for ECT. Discussion. Our project will further clarify the position of ECT in treatment algorithms for depression based on scientific data, including data on cost-effectiveness, cognitive side-effects and needs of the patients in the decision-making process. By these means, it will contribute to the development of successful personalized treatment and preventive strategies also in other countries in cooperation with stakeholders such as national and international commissions.

The authors have declared no competing interest.

This project (with project number 60-63600-98-903) is financed by The Netherlands Organization for Health Research and Development (ZonMW). This organisation reviewed the study protocol during the application process, but has no role in study design, data collection, analysis or publication.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee/IRB of VU University Medical Center, Amsterdam The Netherlands gave ethical approval for this work

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I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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All data produced in the present study are available upon reasonable request to the authors