Table 5. Linear regression: usefulness value.

Predictor	Estimate	SE	Statistic	P value	95% CI
(Intercept)	6.84	0.55	12.50	0.00	(5.76 to 7.93)
Sample	<0.01	<0.01	−1.00	0.32	(−0.01 to 0.00)
Continent of trial conduct
Europe	−0.46	0.36	−1.26	0.21	(−1.18 to 0.26)
North America	0.01	0.43	0.03	0.98	(−0.83 to 0.85)
Journal type
General medicine	−0.45	0.48	−0.93	0.35	(−1.41 to 0.51)
Orthopedics	0.07	0.37	0.19	0.85	(−0.65 to 0.80)
Funding source
Hospital	0.66	0.43	1.54	0.13	(−0.19 to 1.50)
Self-funded/no outside funding	0.93	0.39	2.42	0.02	(0.17 to 1.69)
Impact factor of the journal	0.25	0.09	2.77	0.01	(0.07 to 0.43)