Supplementary file 1_Developing social-cognitive skills in deaf and hard-of-hearing children through a gamified digital intervention: a multisite class-level quasi-experimental study.docx

Introduction<p>This multisite, class-level quasi-experimental study examined whether a 12-week gamified digital intervention was associated with greater improvement in social-cognitive performance among 120 deaf and hard-of-hearing primary-school children from 12 classes in three special education schools in Kazakhstan, compared with an active non-digital programme.</p>Methods<p>The intervention combined visually accessible social scenarios, facial-expression and branching-decision tasks, immediate corrective feedback, repeated attempts, progressive difficulty, and teacher-guided discussion; the comparison condition covered equivalent social-emotional content and instructional time through non-digital activities.

Pre-test and post-test data were collected using a study-specific social-cognitive assessment battery, six non-digital transfer scenarios, and structured classroom and break-time observations. Linear mixed-effects models accounted for repeated measurements, class-level clustering, and study site, with small-sample-corrected inference.</p>Results<p>The experimental group showed a greater increase in the primary social-cognitive composite outcome than the comparison group [adjusted difference = 2.48, 95% CI (0.70, 4.25), p = .011; dDiD = 0.58].