Table 1.
Characteristics of systematic reviews with and without primary studies published in predatory journals (N=100).
| Study characteristics | Contains a primary study published in a suspected predatory journal, n (%) | Chi-square (df) | P value | |||||
|
|
No | Yes | Total |
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|
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| Journal | 3.69 (4,1) | .45 | ||||||
|
|
Journal of the American Academy of Dermatology | 26 (26) | 17 (17) | 43 (43) |
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||
|
|
British Journal of Dermatology | 12 (12) | 4 (4) | 16 (16) |
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||
|
|
Journal of Investigative Dermatology | 1 (1) | 0 (0) | 1 (1) |
|
|
||
|
|
Journal of the European Academy of Dermatology and Venereology | 19 (19) | 8 (8) | 27 (27) |
|
|
||
|
|
Jama Dermatology | 11 (11) | 2 (2) | 13 (13) |
|
|
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| Year of publication | 0.64 (2,1) | .07 | ||||||
|
|
2019 | 24 (24) | 13 (13) | 37 (37) |
|
|
||
|
|
2020 | 30 (30) | 11 (11) | 41 (41) |
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||
|
|
2021 | 15 (15) | 7 (7) | 22 (22) |
|
|
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| Systematic review contained a meta-analysis | 9.38 (1,1) | .002 | ||||||
|
|
No | 20 (20) | 19 (19) | 39 (39) |
|
|
||
|
|
Yes | 49 (49) | 12 (12) | 61 (61) | ||||
| Study received funding | 2.69 (1,1) | .10 | ||||||
|
|
No | 47 (47) | 26 (26) | 73 (73) |
|
|
||
|
|
Yes | 22 (22) | 5 (5) | 27 (27) |
|
|
||
| Includes search from PubMed | 0.06 (1,1) | .81 | ||||||
|
|
No | 36 (36) | 17 (17) | 53 (53) |
|
|
||
|
|
Yes | 33 (33) | 14 (14) | 47 (47) |
|
|
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| Includes search from Web of Science | 0.39 (1,1) | .53 | ||||||
|
|
No | 53 (53) | 22 (22) | 75 (75) |
|
|
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|
|
Yes | 16 (16) | 9 (9) | 25 (25) |
|
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| Includes search from Cochrane | 0.15 (1,1) | .70 | ||||||
|
|
No | 35 (35) | 17 (17) | 52 (52) |
|
|
||
|
|
Yes | 34 (34) | 14 (14) | 48 (48) |
|
|
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| Includes search from Trial Registries | 0.90 (1,1) | .34 | ||||||
|
|
No | 47 (47) | 24 (24) | 71 (71) |
|
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|
|
Yes | 22 (22) | 7 (7) | 29 (29) |
|
|
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| Includes search from Embase | 3.77 (1,1) | .05 | ||||||
|
|
No | 14 (14) | 12 (12) | 26 (26) |
|
|
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|
|
Yes | 55 (55) | 19 (19) | 74 (74) |
|
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| Systematic reviews of RCTsa, NRSIsb, or both | 1.66 (2,1) | .44 | ||||||
|
|
RCTs only | 12 (12) | 4 (4) | 16 (16) |
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|
|
NRSIs only | 37 (37) | 14 (14) | 51 (51) |
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|
|
Both RCTs and NRSIs | 20 (20) | 13 (13) | 33 (33) |
|
|
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| Systematic review had a protocol | 5.78 (1,1) | .02 | ||||||
|
|
No | 41 (41) | 26 (26) | 67 (67) |
|
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|
|
Yes | 28 (28) | 5 (5) | 33 (33) |
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aRCT: randomized controlled trial.
bNRSI: nonrandomized studies of interventions.