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Promotie Annemarie van der Kolk op vrijdag 9 juni aan het Radboud UMC

Promotie Annemarie van der Kolk op vrijdag 9 juni aan het Radboud UMC


Attention Deficit Hyperactivity Disorder (ADHD) is een neurobiologische ontwikkelingsstoornis. In Nederland komt ADHD voor bij ongeveer drie procent van de kinderen (ongeveer 100.000 kinderen). Annemarie van der Kolk onderzocht wat de individuele, sociale en maatschappelijke impact van ADHD is uitgedrukt in kwaliteit van leven en kosten gerelateerd aan de behandelrespons. Deze behandelrespons was in haar onderzoek gebaseerd op een combinatie van functioneren en therapietrouw ten aanzien van medicamenteuze behandeling. Zij toont aan dat de impact van ADHD hoog is op deze verschillende niveaus. De kwaliteit van leven van kinderen met ADHD die geen behandelrespons hebben, is significant lager en de maatschappelijke kosten zijn significant hoger dan van kinderen met een behandelrespons. Een vergelijking van de totale ADHD-groep met een controlegroep toont aan dat kinderen met ADHD zich minder gelukkig, fit en tevreden voelen en hogere kosten maken dan kinderen zonder ADHD.


Annemarie van der Kolk (1984) behaalde in 2007 een masterdiploma Health Prevention and Promotion in Maastricht, en in 2008 een masterdiploma Health Policy, Economics and Management in Maastricht. Bovenstaand onderzoek voerde zij uit bij de afdeling Psychiatrie van het Radboudumc, binnen het Donders Center for Medical Neuroscience, naast haar huidige functie als Market Access Manager bij Janssen-Cilag B.V.

Appendix 1 bevat de verklaring van de begeleiding, samenwerking en financiële ondersteuning van deze promotie

Appendix 1: Support and financial declaration

Financial support by Janssen-Cilag BV, Breda, the Netherlands. A. van der Kolk is an external PhD student of Radboud University Nijmegen as well as an employee of Janssen. As external PhD student, there was no scholarship at Radboud University for execution of the thesis. The support of Janssen on this thesis is part of the general focus on development of employees. Janssen provided the possibilities, but was not involved in the scientific content of the thesis. Janssen funded the fees for use of the respective questionnaires, attendance of congresses for A. van der Kolk, fee for use of the website used for data collection, printing costs, and article-processing fees. No sabbatical was provided by Janssen to pursue this project. Janssen was involved in approval of the study protocols, but solely on the basis of general procedures regarding data collection where privacy aspects and possible safety reporting are checked. Content of the thesis should be attributed to the author, and do not necessarily reflect the company perspective. The start of this project was marked by the employment of A. van der Kolk at Janssen-Cilag BV. Her knowledge and experience on ADHD regarding the perception of the general public on ADHD raised the question for objective data on the impact of ADHD. It was concluded that an objective image on ADHD as a disorder would be of benefit for all parties involved in ADHD, especially for patients and their families.

The project started low key with literature reviews, but eventually the conclusion was drawn that the only way to study this topic objectively would be a scientific study based on data collection and systematic literature review followed by publication of these results via peer-reviewed journals. Based on further discussions, it was concluded that the form of a PhD thesis would be ideal as this would allow for thorough research with dedicated support by experts. The hypotheses was that ADHD would have a major impact, however, at the time this had not been studied in an integrated manner. The results of the study verify the hypothesis. The results of this thesis do not necessarily fulfill a commercial benefit to Janssen. The focus of the thesis is not specifically on treating ADHD with medication, but on treating better – focused on achieving compliance to medication and other treatments for ADHD in general. Four of five papers were published and therefore peer-reviewed by independent experts in the field and available in the public domain. The fifth manuscript is submitted for publication and will be publicly available as well.

The patients’ and parents’ association Balans was not reimbursed for participation. They consented to the data collection via their members by means of an invitation that was added to their quarterly magazine. Balans received the questionnaire, but did not influence the study in any way. The letter as provided to the members of Balans can be found in appendix 2. The website SurveyMonkey was used for the online data collection (www. This website and domain name were based on an account of the Institute for Medical Technology Assessment (iMTA) of the Erasmus University Rotterdam, with which the study was performed. Data generated by the SurveyMonkey questionnaire was assembled in an Excel sheet provided to the iMTA and was shared with A. van der Kolk. Parents/caregivers received a code for entering the website where the questionnaire could be completed, so when a person was not a member of Balans, he or she would have no access to the questionnaire. The questionnaire could be filled in only once per IP address. However, the IP addresses were not traceable by Janssen nor by the iMTA. The choice was made to list iMTA as the sender of the questionnaire to avoid any bias. This was declared towards both Balans and iMTA by means of a letter.

Parents of children with ADHD who participated in the research via Balans were not reimbursed. Respondents in the control group were reimbursed for participating, since this is common practice in this kind of population research. Both samples were not made aware that Janssen was the founder of the study to avoid bias in any way. Promotor prof. dr. J.K. Buitelaar (BIG-nummers 09020377201 and 89020377216) is Professor of Psychiatry and Child- and Adolescent Psychiatry at Radboud University and head of Karakter Child and Adolescent Psychiatry University Centre. He was not reimbursed for his work related to this PhD thesis. Jan Buitelaar has been in the past 3 years a consultant to/member of advisory board and/or speaker for Janssen BV, Eli Lilly, Roche, Lundbeck, Medice, Shire, and Servier. He is not an employee or stock shareholder of any of these companies. He has no other financial or material support, including expert testimony, patents, and royalties. Prof. dr. J.K. Buitelaar has registered his financial relationships in the Dutch Healthcare Transparency Register (DHTR) ( The DHTR is established by physicians, healthcare providers and - institutions and companies with the aim of being transparent concerning the cooperation between healthcare parties. Further information on Dutch regulations on PhD studies and funding for universities can be found in the law on higher education ( Co-supervisor dr. L. Hakkaart-van Roijen from the institute of Medical Technology Assessment (iMTA) of the Erasmus University Rotterdam received reimbursement for time invested, in accordance with iMTA’s standard agreement for external PhD students. She was invited by prof. dr. J.K. Buitelaar to join the project based on her expertise on QoL and societal cost assessment in general and for ADHD specifically.

The study protocols for data collection of both samples as well as the questionnaires for both the ADHD sample and for population controls were drafted in cooperation between all supervisors and A. van der Kolk. The questionnaires were built from three existing questionnaires. Information on these questionnaires and manuals can be found at, and L. Hakkaart-van Roijen has no further conflict of interest. Co-supervisor dr. M. van Agthoven was an employee of Janssen-Cilag BV until September 2014 and did not receive any additional remuneration for his involvement in this PhD thesis. M. van Agthoven worked for Gilead Sciences from October 2014 until June 2016. This company is not involved in psychiatry. His co-supervision from October 2014 until June 2016 has happened fully in leisure time. From July 2016 onwards M. van Agthoven works at Janssen-Cilag BV. The members of the manuscript committee that evaluated this thesis, prof. dr. B.G.M. van Engelen, dr. E.M.M. Adang and prof. dr. F. Boer have no conflict of interest to declare.