Skip to main content

Table 3 Univariable and multivariable logistic regression derived odds ratios (OR) and 95% confidence intervals (CI) for the effect of year of publication, journal, continent of corresponding author, ethical approval, involvement of statistician, trial registration, significance of results, conflict of interest, funding, impact factor and number of authors on the likelihood of SR inclusion

From: Are orthodontic randomised controlled trials justified with a citation of an appropriate systematic review?

Predictor variables Category Univariable analysis Multivariable analysis
OR (95%CI) p-value OR (95%CI) p-value
Journal AJODO Reference    
ANGLE 1.50 (0.59, 3.78) 0.390   
EJO 1.27 (0.54, 3.01) 0.587   
OCR 1.20 (0.32, 4.47) 0.786   
AOJ Not estimable   
JOO Dropped (exactly same % with AJODO)   
JO 1.00 (0.17, 5.88) 1.00   
Continent of corresponding author Europe Reference    
Americas 1.45 (0.50, 4.18) 0.491 1.22 (0.41, 3.61) 0.72
Asia or other 0.41 (0.21, 0.78) 0.007 0.36 (0.18, 0.71) 0.003
Ethical approval No approval or exempt from approval Reference    
Ethical approval obtained 1.69 (0.54, 5.27) 0.367   
Involvement of statistician Not reported Reference    
Reported 1.08 (0.66, 1.76) 0.755   
Trial registration No Reference    
Yes 1.41 (0.75, 2.67) 0.284   
Significance of results Not significant Reference    
Significant 1.00 (0.55, 1.83) 1.000   
Conflict of interest Conflicts exist and declared Reference    
No conflicts to declare 1.09 (0.56, 2.04) 0.782   
Not clearly declared 1.79 (0.20, 15.92) 0.600   
Funding Industry funded and declared Reference    
No industry sponsorship/funding to declare 0.57 (0.29, 1.11) 0.100   
Not clearly declared 0.89 (0.33, 2.38) 0.820   
Year of publication Per unit 1.07 (0.96, 1.18) 0.220 1.09 (0.98, 1.22) 0.11
Impact factor Per unit 1.52 (0.76, 3.06) 0.237   
Number of authors Per unit 1.07 (0.93, 1.22) 0.339