Table 3.
Studies and countries
| Country | Number of studies | References |
| Sweden | 16 with 31 references/papers | 23–26 28–31 45–53 56 60 66 74–78 83 89 92 95 98 99 |
| USA | 12 with 13 references/papers | 27 32 33 35–37 61 62 70 79 82 90 91 |
| Canada | 4 | 38 67 71 90 |
| Germany | 4 | 39 68 84 85 |
| Australia | 3 with 4 references/papers | 34 69 72 90 |
| Hong Kong | 3 | 57 63 88 |
| UK | 3 | 40 41 58 |
| Spain | 2 | 42 64 |
| Brasil | 1 | 81 |
| Denmark | 1 | 54 |
| Iran | 1 | 86 |
| Kenya | 1 | 80 |
| The Netherlands | 1 | 43 |
| New Zealand | 1 | 65 |
| Norway | 1 | 73 |
| Singapore | 1 | 87 |
| Thailand | 1 | 59 |
| Australia, Canada and USA | 1 | 90 |