Table 1.
Characteristics of systematic reviews (N = 1,261) published in 2008a
| Characteristics | Data |
|---|---|
| Citations over a mean of four years, mean (±SD) |
26.5 (28.9) |
| Two-year JIF, mean (±SD; n = 1,101) |
4.3 (4.2) |
| Five-year JIF (mean ± SD; n = 1,016) |
4.6 (4.1) |
| Number of authors, mean (±SD) |
4.3 (2.7) |
| Number of pages, mean (±SD) |
16.0 (25.6) |
| Country location of first author, n (%) |
|
| United Kingdom |
301 (23.9) |
| United States |
285 (22.6) |
| Canada |
145 (11.5) |
| The Netherlands |
83 (6.6) |
| Australia |
83 (6.6) |
| All other countries |
364 (28.9) |
| ICD-10 chapters, n (%) |
|
| Neoplasms |
135 (10.7) |
| Diseases of the circulatory system |
120 (9.5) |
| Factors influencing health status and contact with health services |
119 (9.4) |
| Mental and behavioural disorders |
103 (8.2) |
| Diseases of the digestive system |
103 (8.2) |
| All other ICD-10 codes |
681 (54.0) |
| Intervention type, n (%) |
|
| Not an intervention |
443 (35.1) |
| Drugs and vaccines |
243 (19.3) |
| Surgery and dentistry |
139 (11.0) |
| Investigations, diagnostics or screening |
128 (10.2) |
| Health promotion |
45 (3.6) |
| All other interventions |
263 (20.9) |
| International collaboration, n (%) |
|
| No |
1,057 (83.8) |
| Yes | 204 (16.2) |
aICD-10, International Statistical Classification of Diseases and Related Health Problems, 10th Revision; JIF, journal impact factor.