## 3 Results
### Inside Materials Used in Various Regions  
Figure 4 illustrates the insole materials that have been prescribed in three regions in people with DM [48; 49; 50; 51; 52; 53; 54; 55; 56; 57; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68]. The most common insole materials used at the forefoot regions were EVA (26%), followed by Poron (13%), Plastazote (11%), PU (9%), PPT (5%), and others (36%). Similarly, insole materials used at the midfoot and rearfoot region were EVA (26% and 27%, respectively), followed by Poron, Plastazote, PU, PPT, and others. Figure 3: The PPP at three regions (**A**) forefoot, (**B**) midfoot, and (**C**) rearfoot. The speed was categorized as preferred walking speed in people with DM (4 km/h) and five different speeds in non-DM people (4, 6, 8, 10, and 12 km/h, respectively). PPP, peak plantar pressure; DM, diabetes mellitus; non-DM, healthy people. See the detail of each insole material used for DM people based on the reviewed studies (Tables 2-4). Four studies found that the average PPP reduction using EVA insole material was 38% on the whole foot and 37% on the forefoot region (Table 5). Figure 4: Published paper used insole material under plantar area: (**A**) forefoot, (**B**) midfoot, and (**C**) rearfoot. EVA, ethylene–vinyl acetate; PU, polyurethane; PPT, Professional Protective Technology. The percentage of insole used in the foot region is based on “summary” divided by the total insole used. The term “other” summarizes 11–13 items that do not represent the most used insole material. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Clinical Finding (Reference)** & **EVA** & **Poron** & **Plastazote** & **PU** & **PPT** & **Other** \\ \hline \(\bullet\) & Multi-plug insole reduces DM PPP [50] & – & 1 & 1 & – & – & – \\ \(\bullet\) & Footwear provision for diabetic [57] & 1 & – & – & – & – & 2 \\ \(\bullet\) & Custom orthoses and footwear in diabetic [52] & 1 & – & – & – & – & 5 \\ \(\bullet\) & Cushioning insole in diabetic footwear [62] & – & 1 & 1 & 1 & – & \\ \(\bullet\) & Total contact inside in diminishing foot pressures [54] & 1 & 1 & – & – & – & 1 \\ \(\bullet\) & Diabetic therapeutic footwear on preventing DFUs [64] & – & – & – & 1 & – & \\ \(\bullet\) & Plantar pressure in three types of insole given to DM people [55] & 1 & – & – & 1 & – & 2 \\ \(\bullet\) & Insoles to prevent foot ulceration [66] & 1 & – & – & – & – & 1 \\ \(\bullet\) & Orthotic insoles for people with diabetes [59] & 1 & 1 & – & – & – & – \\ \(\bullet\) & Insoles offloading in the diabetic foot [65] & 1 & – & – & – & 1 & – \\ \(\bullet\) & Cushioned cast reduce foot loading in DM [53] & – & – & – & – & – & 3 \\ \(\bullet\) & Insole materials influence PPP in DM people [60] & – & – & 1 & – & – & 1 \\ \(\bullet\) & Custom insoles enhanced pressure relief [51] & 1 & 1 & – & – & 1 \\ \(\bullet\) & Insoles for the DM neuropathic foot management [67] & 1 & 1 & – & – & – & – \\ \(\bullet\) & Insoles on plantar pressure distribution [48] & 1 & 1 & – & – & – & – \\ \(\bullet\) & Individual robotic insoles in diagnostic and clinical application [68] & – & – & – & – & – & 1 \\ \(\bullet\) & Wearing insoles in different densities [61] & 1 & – & – & – & – & – \\ \(\bullet\) & Different insoles for DM foot [49] & 1 & – & – & 1 & – & 1 \\ \(\bullet\) & Insoles effect for DM people [56] & 1 & – & 1 & – & 1 & 1 \\ \(\bullet\) & Footwear for the diabetic foot [63] & 1 & – & 1 & 1 & 1 & 1 \\ \hline  & **Summary** & 14 & 7 & 6 & 5 & 3 & 20 \\ \hline  & **Percentage** & 26\% & 13\% & 11\% & 9\% & 5\% & 36\% \\ \hline \hline \end{tabular}  
* **Note**: DM, diabetes mellitus; DFUs, diabetic foot ulcers; PPP, peak plantar pressure; EVA, ethylene–vinyl acetate; PU, polyurethane; PPT, Professional Protective Technology.  
\end{table} 
Table 2: The published paper discussed selected insole materials on the forefoot region. \begin{table}