Question	Categories	Scoring options
1. Which assessment instruments/assessment procedures do you use most frequently? For each assessment instrument/assessment method, the following follow‐up questions were asked:		Open question, maximum of five assessment methods
1.1 What does the instrument/assessment method measure? (Multiple answers possible)		Communication, functional abilities, motor skills, sensory/perceptual skills, social adaptive behaviour, social emotional development, cognitive functioning, physical health, quality of life, mental health, other
1.2 What is the type of instrument/assessment method? (Multiple answers possible)		Standardized test, questionnaire, checklist or scale, observation, interview, other
1.3 Who fills in the instrument/assessment method? (Multiple answers possible)		(Developmental) psychologist, physician, direct support professional, physiotherapist, speech therapist, parents (legal guardians).
1.4 How often do you use this instrument/assessment procedure for the purposes mentioned below?	Screening, eligibility, programme planning, progress monitoring, programme evaluation, diagnosis, other	Never, seldom, sometimes, often or always
1.5 What are the reasons for choosing this specific assessment instrument/assessment method?	Feasibility, the specific outcomes of the method, availability, knowledge about the method within the organization, possibility of adapting the method to PIMD, psychometric qualities, costs and that the method was specifically developed for PIMD	Not important, of little importance, neutral, important, very important
1.6 Was this instrument/assessment method specifically developed for the target group?		Yes, no, I don't know
1.7 Did you adapt it for people with PIMD?		Yes, no, I don't know
1.8 Is this instrument/assessment method filled in by more than one person? 1.9 Has information from the different people been integrated?		Yes, no, I don't know Yes, no, I don't know
2. Could you indicate to what extent you experience the barriers mentioned below?	Lack of available methods, communication problems of people with PIMD, health problems of people with PIMD, low alertness of people with PIMD, large number of professionals involved, lack of appropriate resources	Not challenging, slightly challenging, neutral, challenging, very challenging