Page 155 - Demo

Development and validation of the TSC-PROM1536Table 1. continued.Sociodemographic and clinical characteristics Self (n=85) Proxy (n=78)% %Relation to the individual Father 20 25.6 Mother 41 52.6 Sibling 6 10.3 Caretaker 2 6.4 Other 5 5.1* as reported by the primary caregiver or legal representative who completed the questionnaires. Item reductionThe TSC-PROM consisting of 96 items and the five visual analog scales was subjected to item reduction by applying the criteria defined in the method section, unless there was a clinical reason to include based on expert opinion. Two items were included based on expert opinion, namely the burden of seizures and kidneys over the past month. After item reduction, the self version contained 82 items and the proxy version 75 items (physical functions domain 18 items and 19 items with an additional item on side effects, mental functions domain 37 items and 28 items, activities and participation domain 13 items and 14 items, social support 13 items, for self-report and proxy-report respectively) (see Additional file 1). Items in the proxy version that relied on internal perception or were difficult to estimate as a proxy were removed, such as ‘the individual felt lonely’.Structural validityThe mental functions and activities and participation self-report scales displayed sufficient unidimensionality and monotonicity according to the predefined criteria (Table 2). The physical self-report scale and the proxy-report scales did not or only partially satisfy the unidimensionality or monotonicity assumption. Some items within the self-report scale displayed local dependence (residual correlation >0.20; physical functions domain: 4.90%, mental functions domain: 5.03%, activities and participation domain: 5.77%). Within the proxy-report scale, some items showed local dependence (physical functions domain: 8.77%, mental functions domain: 10.46%, activities and participation domain: 9.34%). Annelieke Muller sHL.indd 153 27-11-2023 09:15