Table III.

Summary of the best fitting linear mixed-effects model for the SPL data with the predictors of group, level and set and interaction terms for level and set and level and professional, with the random effect term of subject. The reference levels are level 70, set 2 and group 0.

	Estimate	Std. Error	df	t-value	p-value
Intercept	73.74	1.017	19	72.51	0.0001
Level 80	2.08	0.311	24073	6.69	0.0001
Level 90	4.70	0.311	24073	15.12	0.0001
Set 1	0.73	0.270	24073	2.70	0.0070
Set 3	1.29	0.270	24073	4.78	0.0001
Group 1	4.81	1.421	19	3.39	0.0032
Level 80·Set 1	−0.29	0.381	24073	−0.77	0.4428
Level 90·Set 1	0.09	0.381	24073	0.24	0.8126
Level 80·Set 3	−0.92	0.381	24073	−2.40	0.0164
Level 90·Set 3	−1.34	0.381	24073	−3.52	0.0004
Level 80·Group 1	−0.81	0.311	24073	−2.60	0.0092
Level 90·Group 1	−1.74	0.311	24073	−5.59	0.0001

Significance codes: <0.001; <0.01; <0.05; <0.1