Does the type of competing interest statement affect readers' perceptions of the credibility of research? Randomised trial -- Schroter et al. 328 (7442): 742 Data Supplement

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Table A Analysis of variance results: mean values (95% confidence intervals) and significance levels

	Interest	Importance	Relevance	Validity	Believability
Competing interest*	P=0.12	P=0.035¶	P=0.009**	P<0.001††	P=0.025‡‡
	N 3.21, F 3.06, G 3.26	N 3.29, F 3.03, G 3.16	N 3.44, F 3.13, G 3.35	N 3.16, F 2.82, G 3.12	N 3.49, F 3.20, G 3.36
Paper†	P<0.001	P<0.001	P<0.001	P<0.001	P<0.001
	H 2.90 (2.77 to 3.02)	H 2.84 (2.71 to 2.95)	H 2.30 (2.86, 3.13)	H 2.86 (2.73, 2.99)	H 3.11 (2.98, 3.24)
	P 3.46 (3.35 to 3.57)	P 3.48 (3.37 to 3.59)	P 3.62 (3.50, 3.74)	P 3.20 (3.09, 3.32)	P 3.59 (3.48, 3.71)
Interaction between competing interest and paper	P=0.012§	P=0.31	P=0.29	P=0.23	P=0.007§§
	H: N 3.02, F 2.62, G 3.05	H: N 2.98, F 2.63, G 2.91	H: N 3.18, F 2.72, G 3.09	H: N 3.06, F 2.56, G 2.97	H: N 3.33, F 2.77, G 3.23
	P: N 3.39, F 3.51, G 3.47	P: N 3.60, F 3.43, G 3.41	P: N 3.70, F 3.54, G 3.62	P: N 3.26, F 3.09, G 3.27	P: N 3.65, F 3.63, G 3.49
Age‡	P=0.001	P=0.031	P=0.001	P<0.001	P=0.007
Sex¶¶	P=0.011	P=0.028	P=0.008	P=0.021	P=0.016
	M 3.07, F 3.29	M 3.06, F 3.26	M 3.18, F 3.43	M 2.93, F 3.14	M 3.24, F 3.46

*N=none declared, F=financial statement, G=grants statement.

†H=Herpes paper, P=Problem Lists paper.

‡All ratings increased with age.

§For Herpes paper alone, rating for “financial statement” significantly lower than that for “none declared” and for “grants statement.”

¶Rating for “financial statement” significantly lower than that for “none declared.”

**Rating for “financial statement” significantly lower than that for “none declared.”

††Rating for “financial statement” significantly lower than that for “none declared” and for “grants statement.”

‡‡Rating for “financial statement” significantly lower than that for “none declared.”

§§For Herpes paper alone, rating for “financial statement” significantly lower than that for “none declared” and for “grants statement.”

¶¶M=male, F=female.

Significant interactions between age, sex, and type of competing interest:

Importance: sex´competing interest (P=0.026)

Male: N 3.14, F 2.83, G 3.22

Female: N 3.44, F 3.23, G 3.10

For men alone, the rating for “financial statement” was significantly lower than the other two statements.

Believability: sex´competing interest (P=0.033)

Male: N 3.54, F 3.01, G 3.16

Female: N 3.43, F 3.38, G 3.56

For men alone, the rating for “financial statement” was significantly lower than for “none declared.”