## 4 Results
RQ2: Which Instructional Design Methods Influenced DML Support in the Use of SVREs in Distance Higher Education? The studies used a wide range of learning methods and techniques, with the most prominent being collaborative project-based learning (\(n=10\)) [67; 69; 80], collaborative problem-based learning (\(n=8\)) [66; 86], and collaborative learner-centered learning (\(n=6\)) [81; 96]. Figure 4 is a pictorial representation of the emphasis and use of the aforementioned instructional design methods. When analyzing the level of DML support, we can discern three categories of educational practices in SVREs. There is the top level of innovative practices (\(n=8\)) that supports four or five attributes (active, constructive, intentional, authentic, and cooperative) of meaningful learning [80; 83; 92; 94]. These studies apply methods such as simulations, problem-based learning, and game-based learning with positive results. Several of these studies observe and report directly on the greater depth of student learning and thinking that takes place [67]. In the middle level, twelve studies deployed elaborated constructionist, constructivist, or socio-constructivist practices that supported three attributes of meaningful learning [68; 78; 79]. For three supported attributes, the most frequently occurring combination included the active, authentic, and cooperative attributes (\(n=5\)) [85]. Finally, in the low level, thirteen studies supported two or less attributes of meaningful learning [73; 77; 91]. In these studies, several researchers applied research designs with an emphasis on the control and comparison of specific aspects of the educational experience and not on learning innovation in itself that takes into account the full spectrum of SVRE affordances [6]. However, even these interventions, when well designed and implemented, can lead to deeper levels of thinking and learning [70]. In analyzing and synthesizing the above findings, the recorded degree of SVRE support for DML was overwhelmingly positive, as 85% of the included studies (28 out of 33) reported high or medium support for DML [6]. It is worth mentioning that most studies that were classified as achieving a medium level of DML support only studied and reported favorable results for two of the three DML domains [75; 89]. In other words, it is possible that they also actually achieved positive results in the third missing DML domain, but this fact was not explicitly recorded or reported [6]. Table 5 provides information on the support of DML via SVREs and the number of studies--revealed in this research--that refer to it. Figure 4: Instructional design methods used in the included social virtual reality environment (SVRE) studies. RQ3: What Is the Effectiveness of SVREs in Distance Higher Education According to the Existing Research? Overall, 28 studies reported positive results in the cognitive (\(n=25\)), social (\(n=24\)), and affective (\(n=12\)) domains of research focus. Mixed results were recorded by three studies [26; 87; 93]. No studies yielded negative results. Two studies focused on communication modalities [92] and student perceptions [88] and their results cannot be classified as positive or negative. The most commonly recorded learning effects are summarized in Table 6. In the following, we provide detailed insights about e-learning effectiveness in SVREs in the cognitive, social, and affective dimensions of learning. In particular, the resulted articles researching the cognitive aspects of learning confirmed that distance learning mode interventions in SVREs can improve students' declarative and procedural knowledge [82], knowledge retention [91], higher-order thinking, and problem-solving skills [90]. Furthermore, when learners are active in an SVRE, they become engaged and experience learning gains that improve their performance [78]. Virtual, distant labs in SVREs can effectively support simulated procedural activities to prepare students for professional roles or tasks in the physical world [74; 84].