# A Global Overview of SVA--Spatial-Visual Ability
## 5 Results  
Table 2 provides the frequency distributions for each category of variable.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Variable** & **Category** & **Frequency** & **Percentage—\%** \\ \hline A & 8 & 9.19 \\ B & 8 & 9.19 \\ C & 7 & 8.04 \\ D & 6 & 6.89 \\ E & 5 & 5.74 \\ F & 7 & 8.04 \\ G & 3 & 3.44 \\ H & 0 & 0 \\ I & 0 & 0 \\ J & 2 & 2.29 \\ A + B & 9 & 10.34 \\ A + C & 1 & 1.14 \\ A + D & 1 & 1.14 \\ Sector & A + E & 2 & 2.29 \\ A + G & 4 & 4.59 \\ A + E + G & 1 & 1.14 \\ B + C & 3 & 3.44 \\ B + D & 4 & 4.59 \\ B + I & 2 & 2.29 \\ B + H & 3 & 3.44 \\ B + C + E & 1 & 1.14 \\ B + E + F & 1 & 1.14 \\ C + D & 2 & 2.29 \\ C + E & 3 & 3.44 \\ E + G & 3 & 3.44 \\ E + F & 1 & 1.14 \\ G + H & 1 & 1.14 \\ \hline \multirow{5}{*}{Year} & Y1 & 3 & 3.44 \\  & Y2 & 5 & 5.74 \\  & Y3 & 6 & 6.89 \\ \cline{1-1}  & Y4 & 13 & 14.93 \\ \cline{1-1}  & Y5 & 18 & 20.68 \\ \cline{1-1}  & Y6 & 13 & 14.93 \\ \cline{1-1}  & Y7 & 17 & 19.53 \\ \cline{1-1}  & Y8 & 12 & 13.78 \\ \hline \multirow{5}{*}{Country} & C1 & 46 & 52.85 \\ \cline{1-1}  & C2 & 5 & 5.74 \\ \cline{1-1}  & C3 & 19 & 21.83 \\ \cline{1-1}  & C4 & 13 & 14.93 \\ \cline{1-1}  & C1 + C2 & 2 & 2.29 \\ \hline \multirow{5}{*}{Age Group} & A1 & 2 & 2.29 \\ \cline{1-1}  & A2 & 3 & 3.44 \\ \cline{1-1}  & A3 & 5 & 5.74 \\ \cline{1-1}  & A4 & 4 & 4.59 \\ \cline{1-1}  & A5 & 39 & 44.81 \\ \cline{1-1}  & A6 & 6 & 6.89 \\ \cline{1-1}  & A7 & 15 & 17.23 \\ \cline{1-1}  & A8 & 13 & 14.93 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Frequencies of each category.  
Among the research articles studied, Spatial-visualspatial-visualisation ability has been examined most in the sector of \"STEM, geometry and geography; and Socioeconomic factors, Demographics and Gender Differences (A + B)--10.34%\", which is followed by \"Socioeconomic factors, Demographics and Gender Differences (B)--9.19%\" and \"Architecture, Interior Design, Product Design and Design (C)--9.19%\". Among the 87 research articles reviewed, 42 studies were conducted in two or more sectors, which is also denoted in Table 2.  
In the earliest studies on spatial-visual abilities were conducted in 1979, wherein they were identified and defined by [PERSON] as \"the ability to mentally rotate, manipulate, and twist two- and three-dimensional stimulus objects\" [1]. However, the maximum number of studies was conducted between 2006 and 2010 (Y5) and in the following years, from 2011 onwards (Y6 and Y7), as evident by the numbers in Table 2; the definition and the construct of \"spatial skills\" as an umbrella term have evolved extensively, as have their applications and relevance in the field of cognitive abilities.  
Notably, more than half of the studies were carried out in America (C1)--52.85%. There is a deficit of research on Spatial-visualspatial-visualisation ability, especially in the European and Asian countries, as presented in Table 2. This skewed representation results in biased information and data representation, suggesting that future research directions should be inclusive of the global populace.  
Also evident from the below table is that nearly all the studies were conducted on subjects aged 18 to 22 years old (A5--university and graduate students; 44.81%), followed by studies with mixed-age groups (A7; 17.23%) and studies that did not consider the age of the participants or did not focus on participant-based investigation (NA; 14.93%). Only approximately 16.08% of the studies (A1 + A2 + A3 + A4) concentrate on age groups below 18 years, for whom the developmental research is significant.