From: Over 50 years of trial in Acta Psychiatrica Scandinavica: a survey
 |  | Jadad score | |||
---|---|---|---|---|---|
 |  | 0–2 | 3–5 (good quality) | ||
 | Impact factor | N | N | % | 95% CI |
1950s | - | 7 | 0 | - | - |
1960s | - | 16 | 5 | 23.8 | 11–45 |
1970s | - | 91 | 59 | 39.3 | 32–47 |
1980s | - | 149 | 97 | 39.4 | 34–46 |
1990s | 1.3–1.7 | 70 | 56 | 44.4 | 36–53 |
2000–6 | 1.7–2.4 | 20 | 12 | 37.5 | 23–55 |
Totals |  | 353 | 229 | 39.3 | 35–43 |