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Countries of the 100 top-cited studies.
| Country | Number of studies | Total citation | Average citation |
| USA | 60 | 92,436 | 1,541 |
| England | 13 | 19,050 | 1,465 |
| Canada | 8 | 12,791 | 1,599 |
| Australia | 5 | 4,467 | 893 |
| France | 3 | 3,284 | 1,095 |
| Scotland | 2 | 25,039 | 12,520 |
| Denmark | 2 | 2,351 | 1,176 |
| Netherlands | 2 | 2,306 | 1,153 |
| Italy | 2 | 1,986 | 993 |
| Norway | 1 | 849 | 849 |
| Israel | 1 | 806 | 806 |
| Spain | 1 | 758 | 758 |
