. Author manuscript; available in PMC: 2021 Jun 9.

Published in final edited form as: Dev Psychol. 2020 Jan 30;56(4):783–794. doi: 10.1037/dev0000894

Table 4.

Model Summaries for Change in RSA Reactivity From Age 2 to Age 15

Parameters	Unconditional	Linear	Quadratic	Bilinear	Quadratic-linear
Fixed effects
Intercept	0.544 (0.026)^***	−1.216 (0.098)^*	−1.064 (0.105)^***	−1.420 (0.120)^***	−1.211 (0.119)^***
Slope^a	—	−0.0007 (0.0004)^†	−0.008 (0.002)^***	−0.003 (0.001)^***	0.023 (0.003)^***
Acceleration^a	—	—	0.00003 (0.000008)^***	—	0.0004 (0.00005)^***
Slope^b	—	—	—	0.0007 (0.0006)	−0.002 (0.0007)^*
Resting RSA	—	0.290 (0.016)^***	0.314 (0.017)^***	0.300 (0.017)^***	0.295 (0.016)^***
Random effects
Intercept	0.075 (0.016)	0.100 (0.017)	0.107 (0.017)^***	0.136 (0.026)^***	0.151 (0.026)^***
Slope^a	—	—	—	0.00001 (0.00002)^†	0.00002 (0.00002)^*
Residual	0.529 (0.023)	0.399 (0.017)	−0.387 (0.017)	0.387 (0.019)	0.353 (0.018)
Model summary
AIC	3,114.34	2,791.96	2,779.52	2,788.45	2,700.49
BIC	3,129.95	2,820.05	2,810.71	2,830.03	2,747.27
LL	−1,554.17	−1,392.03	−1,383.76	−1,386.23	−1,341.25

Note. Model comparisons: linear vs. quadratic, p < .001; linear vs. bilinear, p < .01; quadratic vs. bilinear, p < .10; quadratic vs. quad-linear, p < .001; bilinear vs. quad-linear, p < .001. RSA = respiratory sinus arrhythmia; AIC = Akaike information criterion; BIC = Bayesian information criterion; LL = log-likelihood.

Spline 1.

Spline 2.

^†

p < .10.

p < .05.

^***

p < .001.