Table 4.

Factors associated with LMC authorship in oncology RCTs

	Univariate logistic regression		Multivariable logistic regression
Variable	OR (95% CI)	p-value	OR (95% CI)	p-value
Year
For every 1-year increase	1.11 (1.02 – 1.20)	0.01	1.12 (1.02 – 1.24)	0.02
Site
Lung	1.00	Referent	1.00	Referent
Breast	1.38 (0.82 – 2.33)	0.22	1.34 (0.70 – 2.56)	0.38
Liver/colorectal/stomach	0.66 (0.34 – 1.27)	0.21	0.52 (0.24 – 1.10)	0.09
Funding
Not for profit/Mixed	1.00	Referent	1.00	Referent
Industry	3.63 (2.00 – 6.58)	<.0001	3.54 (1.85 – 6.78)	0.0001
Not specified	0.88 (0.44 – 1.79)	0.73	0.95 (0.45 - 2.03)	0.90
Multi-center
No	1.00	Referent	1.00	Referent
Yes	1.24 (0.77 – 2.00)	0.38	0.91 (0.52 – 1.58)	0.74
Placebo-controlled
No	1.00	Referent	1.00	Referent
Yes	3.08 (1.57 – 6.07)	0.001	2.57 (1.19 – 5.54)	0.02
Treatment type
Basic/Limited	1.00	Referent	1.00	Referent
Enhanced/Maximal	1.11 (0.68 – 1.82)	0.68	0.61 (0.32 – 1.16)	0.13
Treatment aim
Adjuvant	1.00	Referent	1.00	Referent
Both	3.67 (1.48 – 9.06)	0.005	5.12 (1.81 – 14.48)	0.002
Metastatic	3.38 (1.75 – 6.55)	0.0003	4.00 (1.90 – 8.43)	0.0003
Supportive measures	2.67 (0.91 – 7.79)	0.07	1.21 (0.35 – 4.17)	0.76
Design
Factorial/multiple arms	1.00	Referent	1.00	Referent
Simple 2 arm	0.96 (0.49 – 1.90)	0.91	0.73 (0.34 – 1.58)	0.43
Ethics
Not documented	1.00	Referent	1.00	Referent
Documented	1.36 (0.73 – 2.54)	0.33	0.76 (0.37 – 1.56)	0.45

Outcome variable is having at least one LMC author.