Acknowledgements
This study was funded by the Health Care Efficiency Research grant (number 945–04–263) from the Netherlands Organisation for Health Research and Development, a Dutch governmental organisation, and by internal funding through a Health Care Efficiency grant from the Erasmus University Medical Center, Rotterdam. The authors’ work was independent of the funding organisations. The funding organisations had no involvement in the design or conduct of this study; data management and analysis; or manuscript preparation and review or authorisation for submission.

Open Access
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