# High-Functioning Autism and Virtual Reality Applications: A Scoping Review
## 3 Results  
### Features of the Included Studies  
The number of records identified in the databases through the search string was 975. After preliminary screening based on the title and abstracts, 146 articles were considered suitable for the second step, which encompassed reading the full texts and distinguishing the works by the type of VR used. Of the 146 papers, 71 did not involve immersive or semi-immersive VR, and 17 were theoretical/methodological and thus discarded. Then, the 58 selected were screened to identify only those focusing on HFA. This resulted in 23 eligible papers included in this review, of which there were five conference proceedings and 18 full journal papers, as shown in Figure 1.  
Table 1 provides an overview of the main characteristics of the included studies. Most of the studies were conducted in North America (nine papers) and Europe (eight papers), with fewer contributions from Asia (five papers) and Australia (one paper). Figure 1: Flowchart of the paper selection process. +++ ==ERROR: No output for this page==
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Fast Author, Yote and Reference** & **Country** & **Study Type** & **Type of V/V** & **Total Sample Ob, Sec (no, E, R, and Age Range)** & **IQ and Test (of Available)** & **Aims** & **Task** \\ \hline
**Isoberg/skin 2017 [50]** & USA & QE & HMD & 9.3 AJ2 norm & 20.24 \(\pm\) 3.4 & IQ-5.00 & To explore the effectiveness of a virtual reality system within its traditional individuals with SQL on \\  &  
Figure 2 shows the temporal distribution of publications from 2002 to April 2021. The majority of the studies were classified as quasi-experimental (65.2%), whereas a minority were true experimental (17.4%) or pre-experimental (17.4%) studies. Both quasi-experimental and true experimental types aim to manipulate the independent variables to register expected outcomes on the dependent ones. The main difference is that researchers, in quasi-experiments, do not perform a randomized assignment of the participants to the conditions. On the other hand, in pre-experimental studies, participants are usually observed before and after a treatment (one group pre-test/post-test) to see if it generates potential changes [67]. Table 2 reports the classification of the included papers accordingly. Regarding the study design, the majority of the studies were \"single group\" (N = 12), followed by \"two-group\" (N = 9) and \"single-subject\" designs (N = 2). The population of the experimental studies included in the current review involved both healthy subjects and participants with ASD: 9 publications (39.1%) involved more than 30 participants, whereas 14 included fewer than 30 participants (60.9%). Finally, the number of ASD participants involved in the 23 studies was higher than that of the healthy controls (494 and 215, respectively). The number of participants, grouped as ASD and healthy subjects, for each of the 23 publications is presented in Figure 3. Overall, the sample size ranged from 2 to 94 participants. The majority of the studies focused on participants below 18 years of age (N = 13, 56.5%), whereas a smaller number of papers included participants above 18 years (N = 9, 39.1%). Only one paper (4.4%) included participants both above and below 18 years. \begin{table}
\begin{tabular}{c c c} \hline
**Type of Research** & N & \% \\ \hline Quasi-experimental & 15 & 65.2 \\ True experimental & 4 & 17.4 \\ Pre-experimental & 4 & 17.4 \\ \hline \end{tabular}
\end{table} 
Table 2: Classification of the included papers according to the definition of [PERSON] and [PERSON] [67]. N: number of papers. Figure 2: Number of publications by year. Considering the technology (Table 3), HMDs were used in most of the studies (15 papers, 65.2%). Only five studies (21.7%) focused on semi-immersive VR, followed by immersive CAVE (three papers, 13.1%).