Table 1 Characteristics of all included papers and purposively sampled texts
|  | 1990 and before | 1991–2000 | 2001–2010 | 2011–2016 | ||||
|---|---|---|---|---|---|---|---|---|
All papers included n = 12 | Purposively sampled n = 6 | All papers included n = 23 | Purposively sampled n = 8 | All papers included n = 68 | Purposively sampled n = 25 | All papers included n = 104 | Purposively sampled n = 28 | |
n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |
Language | ||||||||
 English | 9 (75) | 4 (67) | 14 (60) | 6 (75) | 41 (60) | 14 (56) | 77 (74) | 22 (79) |
 Spanish | 2 (17) | 1 (17) | 9 (40) | 2 (25) | 19 (28) | 9 (36) | 16 (15) | 5 (18) |
 Portuguese | 1 (8) | 1 (17) | 0 | 0 | 8 (12) | 2 (8) | 10 (10) | 1 (4) |
Region | ||||||||
 Central America | 6 (50) | 3 (50) | 6 (26) | 2 (25) | 7 (11) | 5 (20) | 17 (16) | 3 (11) |
 South America | 2 (17) | 1 (17) | 4 (17) | 1 (12) | 26 (39) | 7 (28) | 52 (50) | 15 (54) |
 Latin America | 4 (33) | 2 (33) | 13 (57) | 5 (63) | 29 (43) | 10 (10) | 27 (26) | 6 (21) |
 Central and South America | 0 | 0 | 0 | 0 | 6 (9) | 3 (12) | 8 (8) | 4 (14) |
Primary research | ||||||||
 Yes | 1 (8) | 1 (17) | 7 (30) | 2 (25) | 23 (34) | 5 (20) | 48 (46) | 8 (29) |
 No | 11 (92) | 5 (83) | 16 (70) | 6 (75) | 45 (66) | 20 (80) | 56 (54) | 20 (71) |
Type of research paper | ||||||||
 Quantitative | 0 | 0 | 4 (17) | 1 (12.5) | 14 (21) | 3 (12) | 31 (30) | 4 (14) |
 Qualitative | 1 (8) | 1 (17) | 3 (13) | 1 (12.5) | 7 (10) | 1 (4) | 15 (14) | 4 (14) |
 Mixed methods | 0 | 0 | 0 | 0 | 2 (3) | 1 (4) | 2 (2) | 0 |
Type of non-research papers | ||||||||
 Situation analysis | 3 (25) | 0 | 6 (26) | 3 (37.5) | 11 (16) | 6 (24) | 11 (11) | 5 (18) |
 Discussion paper | 5 (42) | 4 (67) | 5 (22) | 1 (12.5) | 20 (29) | 11 (44) | 19 (18) | 9 (32) |
 Other | 3 (25) | 1 (17) | 5 (22) | 2 (25) | 14 (21) | 3 (12) | 26 (25) | 6 (21) |