*3.2. Aim (2) Propose Measurement Scales to Assess Each ICF Category. Development of a Toolbox*

All selected scales are used regularly in assessments of ASD, and the study team is trained in their use. The selection of the tools was based on consensus. From each tool we selected the item/s that best covered the content of the ICF category (Table 1). Experts from other national and international institutions were consulted to provide feedback on the proposed toolbox.

#### *3.3. Aim (3) Feasibility and Psychometric Properties of TEA-CIFunciona*

We showed that TEA-CIFunciona was reliable, relevant, and feasible for application in our busy clinical consultations. After we piloted the first version of TEA-CIFunciona, we revised the tool based on parents' and professionals' feedback. Hence, two categories were added, as follows: Individual attitudes of people in positions of authority (e430) and Associations and organizational services, systems, and policies (e555). Two categories (b125 and b140) showed a lower level of agreement than expected; therefore, it was agreed to prioritize parents' opinion and they scored the categories using the VAS.
