Table 4. Optimal models found for Eqs 4 & 5.

Regression output	Eq 4 DP ~ PA4RMS + (PA4RMS |Participant)	Eq 5 DP x NJI ~ PA6RMS + (1|Participant)
FE β Coefficient *	-2.18	-1.02
FE Standard error*	0.51	0.33
P-value	<0.005	<0.005
RE-Participant intercepts variance*	3.08	2.27
RE-Participant slopes variance*	1.37	-
RE-residual variance*	3.84	5.32
Inter-class coefficient (ICC)	0.44	0.34
Pseudo-R2 (Fixed-effects only)	0.37	0.17
Pseudo-R2 (Total)	0.70	0.45
Restricted-Maximum Likelihood	178.3	196.3

(*FE = Fixed effect, RE = Random effect).