Funding for this research was provided by:
Received: 9 August 2021
Accepted: 24 August 2021
First Online: 6 September 2021
: Our research is conducted in accordance with the principles of the Declaration of Helsinki (64th WMA General Assembly, October 2013) and in accordance with the Dutch law (Social Support Act and Medical Treatment Agreement Act). Ethical approval of the current study was obtained for all care provider services by the Ethics Committee of the Erasmus University Medical Center Rotterdam in the Netherlands (MEC 2016–573). The Central Committee on research involving human subjects (CCMO) has also issued an extension “No grounds for non-acceptance” to execute this study. The EudraCT number of this study is 2016–002859-19. Written informed consent will be obtained from all participants and/or their legal representatives; see 3.3.2 ‘recruitment and informed consent procedure’. The guideline of the Dutch Association of Intellectual Disability Physicians will be applied if there is resistance during the measurements. This means that if a participant shows verbal or non-verbal resistance before or during a test or measurement, it will not be performed or completed. Behaviour will be interpreted as resistance if behaviour is different from regular behaviour that the participant shows in everyday situations. This will be determined by a caregiver who the participant trusts and knows well.
: Not applicable.
: The authors declares that they have no competing interests.