Table 3.

Partial correlations between sleep parameters (Nights 1 and 2) and Day 2 digit span backward performance (controlling for Day 1 digit span backward performance) within the patients with Parkinson's disease taking dopaminergic medication

Sleep variables	Night 1 (pre-training)	Night 2 (during training)
Total sleep time	0.059	−0.049
Sleep efficiency	0.087	−0.023
Sleep latency	0.079	0.023
% Stage 1	−0.068	−0.156
% Stage 2	−0.160	−0.195
% Slow-wave sleep	0.304	0.373*
% REM	0.089	0.155
AHI	−0.141	−0.005
PLMS index	0.146	0.108
Dream enactment	0.094	0.061
Lowest SaO2	0.112	0.188
Sa02 <90% (min)	−0.018	−0.318

*P < 0.05, after adjusting for multiple testing using the Hochberg method (Norman and Steiner, 2000).

AHI = apnoea–hypopnoea index; PLMS = periodic leg movements; SaO₂ = oxygen saturation.