Table 1. Number of human studies and sample size by participant sex overall and for each DRI report section.
| Characteristics | Section in the DRI reports | |||
| Indicator | Life stages | Upper level | Total | |
| Number of studies | N = 233 | N = 336 | N = 102 | N = 671 |
| Included women | 157 (67.4%) | 285 (84.8%) | 78 (76.4%) | 520 (77.5%) |
| Included pregnant or lactating women* | 12 (5.2%) | 98 (29.2%) | 7 (6.9%) | 117 (17.4%) |
| Men only | 58 (24.9%) | 38 (11.3%) | 15 (14.7%) | 111 (16.5%) |
| Sex unspecified | 18 (7.7%) | 13 (3.9%) | 9 (8.8%) | 40 (6.0%) |
|
Sample size among 640 studies reporting
sample size by sex † |
n = 674,522 | n = 53,646 | n = 185,997 | n = 914,137 |
| Sample size of all women, n (%) | 190,818 (28.3%) | 30,220 (56.3%) | 42,884 (23.1%) | 263,922 (28.9%) |
| Pregnant or lactating women, n (%)‡ | 482 (0.1%) | 18,144 (33.8%) | 23,521 (12.6%) | 42,147 (4.6%) |
| Sample size of all men, n (%) | 483,704 (71.7%) | 23,398 (43.6%) | 143,113 (76.9%) | 650,215 (71.1%) |
| Sample size of men in studies that only included men, n (%)§ |
404,362 (59.9%) | 1,015 (1.9%) | 284 (0.2%) | 405,629 (44.4%) |
*Studies that included pregnant or lactating women are nested within studies that included women; we combined pregnant and lactating women into the same category.
†Sample size with unspecified sex: n = 46,086, n = 782, and n = 4393 in the indicator, life stages, and upper level sections, respectively (total = 51,261).
‡Not all studies reported sample size for women or pregnant women, even when they were included.
§Subset of the “men” category.