Colofon © Copyright Pishtiwan Kalmet, 2022 All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means, without prior permission in writing by the author, or when appropriate, by the publishers of the publications. Cover design: Ilse Modder, grafisch ontwerper Layout: Tiny Wouters Production: Gildeprint ISBN: 978-94-6419-566-8 The work described in this thesis has received funding by the Netherlands Organization for Health Research and Development (ZonMW, project number 843001807). The insole material for this study was provided by the AO Foundation TK System (AOTK Project number: AO516.05). The funders had no role in the design and conduct of the study; in the collection, management, analysis and interpretation of the data; in the preparation, review, or approval of the manuscript; or in the decision to submit the manuscript for publication. Financial support by the Maastricht University for the publication of this thesis is gratefully acknowledged.