Table 5.
Univariate and multivariate binary logistic regression analysis for the reporting COI at website
| Univariate (No COI reporting as the reference category) | Multivariate (all variables included) | Multivariate (backward selection) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Variables | B | OR (95%CI) | P | B | OR (95%CI) | P | B | OR (95%CI) | P |
| Type of primary studies based on the full-text | 0.61 | ||||||||
| In-vitro or animals | Ref | ||||||||
| Humans | -0.04 | 0.96 (0.48–1.92) | 0.91 | ||||||
| Both | -0.77 | 0.46 (0.10–2.24) | 0.34 | ||||||
| Review type | |||||||||
| Intervention | Ref | ||||||||
| Non-intervention | 0.24 | 1.27 (0.78–2.06) | 0.34 | ||||||
| Review registration based on full-text | |||||||||
| Yes | Ref | ||||||||
| No | -0.26 | 0.77 (0.52–1.16) | 0.21 | ||||||
| Continents of origin of the reviews | 0.48 | ||||||||
| North America | Ref | ||||||||
| South America | -0.23 | 0.80 (0.38–1.67) | 0.55 | ||||||
| Europe | -0.27 | 0.76 (0.38–1.52) | 0.44 | ||||||
| Asia | 0.21 | 1.24 (0.63–2.42) | 0.53 | ||||||
| Africa | - | - | - | ||||||
| Oceania | -0.03 | 0.97 (0.29–3.22) | 0.96 | ||||||
| Countries of origin of the reviews | |||||||||
| Developing | Ref | ||||||||
| Developed | -0.15 | 0.86 (0.58–1.29) | 0.47 | ||||||
| Abstract type | |||||||||
| Structured | Ref | Ref | Ref | ||||||
| Non-structured | -0.83 | 0.43 (0.25–0.74) | < 0.01* | -0.75 | 0.48 (0.28–0.82) | < 0.01* | -0.73 | 0.48 (0.28–0.83) | < 0.01* |
| Review access based on homepage | |||||||||
| Yes | Ref | Ref | |||||||
| No | 0.63 | 1.87 (1.25–2.79) | < 0.01* | 0.19 | 1.21 (0.78–1.86) | 0.40 | |||
| Review access based on internet | |||||||||
| Yes | Ref | ||||||||
| No | 0.12 | 1.12 (0.52–2.43) | 0.77 | ||||||
| Journal type | |||||||||
| Dentistry | Ref | ||||||||
| Other | -0.34 | 0.71 (0.40–1.26) | 0.24 | ||||||
| Journal access | |||||||||
| Subscription or hybrid | Ref | Ref | Ref | ||||||
| Open access | -1.40 | 0.25 (0.14–0.45) | < 0.01* | -1.25 | 0.29 (0.15–0.54) | < 0.01* | -1.35 | 0.26 (0.14–0.47) | < 0.01* |
| Journal reporting a COI policy in the instructions to authors | |||||||||
| Yes | Ref | ||||||||
| No | -0.30 | 0.74 (0.17–3.23) | 0.69 | ||||||
| Journal reporting the type of COI in the instructions to authors | 0.63 | ||||||||
| Financial | Ref | ||||||||
| Non-financial | - | - | - | ||||||
| Both | -0.25 | 0.78 (0.42–1.47) | 0.44 | ||||||
| Only say that authors need to report COI | -1.03 | 0.36 (0.10–1.32) | 0.12 | ||||||
| No information | -0.55 | 0.58 (0.12–2.77) | 0.49 | ||||||
| Journal impact factor** | 0.03 | 1.03 (0.91–1.17) | 0.63 | ||||||
| Number of citations*** | -0.002 | 0.998 (0.995–1.001) | 0.21 | ||||||
| Number of authors | -0.02 | 0.98 (0.91–1.06) | 0.59 | ||||||
| Nagelkerke R2 | Not applicable | 0.076 | 0.075 | ||||||