. 2016 Oct 28;90(1):93–106. doi: 10.1007/s00420-016-1175-x

Table 3.

Associations between tremor parameters and cumulative exposure by level of sCotinine

Tremor parameters	sCotinine ≥ 5 (µg L⁻¹)^a (N = 56)				sCotinine < 5 (µg L⁻¹)^b (N = 39)
	β-Estimate	95% CI			β-Estimate	95% CI		P
	β-Estimate	Lower bound	Upper bound	p	β-Estimate	Lower bound	Upper bound	P
Postural tremor dominant hand
Tremor Intensity (ms⁻²)	0.019	0.005	0.033	0.009	−0.008	−0.018	0.002	0.12
Center Frequency (Hz)	0.29	0.09	0.50	0.006	0.13	−0.17	0.44	0.37
Frequency Dispersion (Hz)	−0.04	−0.15	0.06	0.42	0.10	−0.08	0.27	0.27
Harmonic Index	−0.004	−0.01	0.003	0.23	−0.001	−0.008	0.006	0.76
Postural tremor non-dominant hand
Tremor Intensity (ms⁻²)	0.02	0.007	0.04	0.006	−0.001	−0.008	0.006	0.79
Center Frequency (Hz)	0.40	0.20	0.61	<0.001	0.18	−0.04	0.41	0.10
Frequency Dispersion (Hz)	0.04	−0.06	0.15	0.41	0.05	−0.10	0.20	0.54
Harmonic Index	−0.003	−0.011	0.005	0.49	−0.001	−0.009	0.007	0.81
Rest tremor dominant hand
Tremor Intensity (ms⁻²)	0.013	0.002	0.023	0.02	−0.001	−0.01	0.007	0.73
Center Frequency (Hz)	−0.05	−0.24	0.14	0.60	0.11	−0.09	0.30	0.28
Frequency Dispersion (Hz)	−0.13	−0.27	0.006	0.06	−0.01	−0.20	0.17	0.88
Harmonic Index	0.00009	−0.005	0.005	0.97	−0.003	−0.009	0.003	0.35
Rest tremor non-dominant hand
Tremor Intensity (ms⁻²)	0.012	0.003	0.02	0.01	−0.001	−0.01	0.007	0.73
Center Frequency (Hz)	0.09	−0.12	0.30	0.39	0.03	−0.27	0.33	0.85
Frequency Dispersion (Hz)	−0.20	−0.35	−0.05	0.01	0.02	−0.17	0.20	0.84
Harmonic Index	0.002	−0.002	0.007	0.31	0.0	−0.007	0.007	0.97

^a sCotinine concentration: 576 µg L⁻¹ (range 8.5–1744 µg L⁻¹)

^b sCotinine concentration: 0 µg L⁻¹