Table 2 Characteristics of included publications
From: An analysis of key indicators of reproducibility in radiology
Characteristic | Original sample N (%) | Â | Validation sample N (%) | |
|---|---|---|---|---|
Type of studyN= 294 | No empirical data | 79 (26.9) | Type of studyN= 198 | 44 (22.2) |
Clinical trial | 55 (18.7) | 55 (27.8) | ||
Laboratory | 44 (15.0) | 43(21.7) | ||
Chart review | 42 (14.3) | 12 (6.1) | ||
Cohort | 19 (6.5) | 18 (9.1) | ||
Case study | 18 (6.1) | 11 (5.6) | ||
Survey | 12 (4.1) | 3 (1.5) | ||
Cost effect | 7 (2.4) | 4 (2.0) | ||
Case control | 6 (2.0) | 1 (0.5) | ||
Cross-sectional | 5 (1.7) | 3 (1.5) | ||
Meta-analysis | 4 (1.4) | 0 (0.0) | ||
Case series | 2 (0.7) | 3 (1.5) | ||
Multiple | 1 (0.3) | 1 (0.5) | ||
Other | 0 (0.0) | 0 (0.0) | ||
Test subjectsN= 294 | Humans | 167 (56.8) | Test subjectsN= 198 | 108 (54.6) |
Neither | 116 (39.5) | 77 (38.9) | ||
Animals | 11 (3.7) | 13 (6.6) | ||
Both | 0 (0) | 0 (0) | ||
Country of journal publicationN= 294 | US | 209 (71.1) | Country of journal publicationN= 198 | 128 (64.7) |
UK | 44 (15.0) | 36 (18.2) | ||
Germany | 6 (2.0) | 8 (4.04) | ||
France | 5 (1.7) | 7 (3.54) | ||
Japan | 3 (1.0) | 5 (2.53) | ||
Canada | 3 (1.0) | 0 (0.0) | ||
Italy | 2 (0.7) | 0 (0.0) | ||
India | 1 (0.3) | 0 (0.0) | ||
Other | 21 (7.14) | 14 (7.1) | ||
Country of corresponding authorN= 294 | US | 102 (34.7) | Country of corresponding authorN= 198 | 74 (37.4) |
China | 19 (6.5) | 13 (6.6) | ||
Germany | 17 (5.8) | 16 (8.1) | ||
Japan | 17 (5.8) | 12 (6.1) | ||
Australia | 15 (5.1) | 11 (5.6) | ||
South Korea | 14 (4.8) | 12 (6.1) | ||
Turkey | 13 (4.4) | 3 (1.5) | ||
Canada | 13 (4.4) | 3 (1.5) | ||
UK | 9 (3.1) | 7 (3.5) | ||
Netherlands | 9 (3.1) | 6 (3.0) | ||
France | 8 (2.7) | 9 (4.5) | ||
Switzerland | 7 (2.4) | 5 (2.5) | ||
India | 5 (1.7) | 2 (1.0) | ||
Italy | 5 (1.7) | 2 (1.0) | ||
Spain | 3 (1.0) | 0 (0.0) | ||
Unclear | 2 (0.7) | 0 (0.0) | ||
Other | 36 (12.2) | 23 (11.6) | ||
Open accessN= 300 | Yes  found via open-access button | 80 (26.7) | Open accessN= 198 | 67 (33.8) |
Yes  found article via other means | 71 (23.7) | 23 (11.6) | ||
Could not access through paywall | 149 (49.7) | 108 (54.5 | ||
5-year impact factorN= 272 | Median | 2.824 | 5 -year impact factorN= 182 | 2.89 |
1st quartile | 1.765 | 2.02 | ||
3rd quartile | 3.718 | 3.55 | ||
Interquartile range | 1.953 | 1.53 | ||
Most recent impact factor yearN= 300 | 2017 | 266 | Most recent impact factor yearN= 200 | 0 |
2018 | 10 | 186 | ||
Not found | 24 | 14 | ||
Most recent impact factorN= 276 | Median | 2.758 | Most recent impact factorN= 186 | 2.68 |
1st quartile | 1.823 | 1.94 | ||
3rd quartile | 3.393 | 3.79 | ||
Interquartile range | 1.57 | 1.85 | ||
Cited by systematic review or meta-analysisN= 211 | No citations | 193 (91.5) | Cited by systematic review or meta-analysisN= 151 | 132 (87.4) |
A single citation | 11 (5.2) | 13 (8.6) | ||
One to five citations | 7 (3.3) | 6 (4.0) | ||
Greater than five citations | 0 (0) | 0 (0) | ||
Excluded in SR or MA | 0 (0) | 0 (0) | ||
Cited by replication studyN= 211 | No citations | 211 (100) | Cited by replication studyN= 151 | 151 (100) |
A single citation | 0 (0) | 0 (0) | ||
One to five citations | 0 (0) | 0 (0) | ||
Greater than five citations | 0 (0) | 0 (0) | ||
Excluded in SR or MA | 0 (0) | 0 (0) | ||