Table 3.

Number of papers by countries as study settings (N=749).

Rank	Country settings	Frequency, n (%)
1	United States	348 (46.5)
2	Ireland	47 (6.3)
3	Taiwan	44 (5.9)
4	Japan	41 (5.5)
5	United Kingdom	37 (4.9)
6	India	33 (4.4)
7	China	25 (3.3)
8	Australia	22 (2.9)
9	Italy	14 (1.9)
10	Mali	12 (1.6)
11	Sweden	11 (1.5)
12	Wallis and Futuna	10 (1.3)
13	Germany	9 (1.2)
14	Netherlands	9 (1.2)
15	Poland	9 (1.2)
16	France	7 (0.9)
17	Spain	7 (0.9)
18	Denmark	6 (0.8)
19	Hong Kong	6 (0.8)
20	Canada	5 (0.7)
21	Finland	5 (0.7)
22	Iran	5 (0.7)
23	Singapore	4 (0.5)
24	Belgium	3 (0.4)
25	Brazil	3 (0.4)
26	Egypt	3 (0.4)
27	Israel	3 (0.4)
28	Malaysia	3 (0.4)
29	Turkey	3 (0.4)
30	New Zealand	2 (0.3)
31	Norway	2 (0.3)
32	Antarctica	1 (0.1)
33	Austria	1 (0.1)
34	Georgia	1 (0.1)
35	Greece	1 (0.1)
36	Iceland	1 (0.1)
37	Indonesia	1 (0.1)
38	Jersey	1 (0.1)
39	Jordan	1 (0.1)
40	Pakistan	1 (0.1)
41	Saint Pierre	1 (0.1)
42	Saudi Arabia	1 (0.1)