. Author manuscript; available in PMC: 2019 Jan 1.

Published in final edited form as: J Exp Psychol Gen. 2017 Oct 23;147(1):139–146. doi: 10.1037/xge0000374

Table 2.

Results of hierarchical linear regression analysis on sleep onset latency. Mean arterial pressure is collapsed across pre- and post-writing observations.

	Without Covariates			With Covariates
	Step 1	Step 2	Step 3	Step 1	Step 2	Step 3	Step 4
Mean Arterial pressure				β = .29^*	β = .33^*	β = .33^*	β = .30^*
Sleep Diary SOL				β = .30^*	β = .28^*	β = .27^*	β = .23^†
Writing List Condition	β = −.30^*	β = −.29^*	β = .44		β = −.30^*	β = −.29^*	β = .20
List Specificity (number of items written)		β = −.07	β = .46^*			β = −.06	β = .29
Condition x List Specificity Interaction			β = −1.02^**				β = −.67^†
F statistic	F(1,55) = 5.40	F(1,54) = 0.31	F(1,53) = 7.75	F(2,50) = 6.83	F(1,49) = 6.15	F(1,48) = 0.23	F(1,47) = 3.64
ΔR²	.089^*	.005	.12^**	.215^**	.088^*	.003	.050^†

Abbreviations: PRMQ = Prospective and Retrospective Memory Questionnaire; SOL: sleep onset latency

^†

indicates p < .10,

indicates p < .05,

^**

indicates p < .01.