“…Therefore, linguistically oriented models such as that developed by Hopp et al (2010) provide a basis for planning specific training programs for language support. Training programs administered in studies investigating knowledge and skills focused on different content, i.e., on the usage of LSS (Beckerle et al, 2019) or on linguistic and practical knowledge (Roth et al, 2015;Lemmer et al, 2019). Overall, these studies found positive effects of intervention programs on the caregivers' knowledge and theoretical competencies (Roth et al, 2015;Beckerle et al, 2019).…”