Table 4.

Graded stimulus volume-esophageal reflex response relationships across maturation and during sleep vs. awake states

		Awake - Time 1		Awake - Time 2		Sleep - Time 1		Sleep - Time 2
Reflex	Media	Odds Ratio (95% CI)	P Value	Odds Ratio (95% CI)	P Value	Odds Ratio (95% CI)	P Value	Odds Ratio (95% CI)	P Value
UES contractile reflex	Air	1.2 (0.9–1.4)*	0.06	3.5 (1.7–6.9)*	0.0004	1.9 (1.1–3.3)	0.02	1.6 (0.98–2.7)	0.06
	Water	10.9 (0.4–308)	0.2	2.8 (0.6–12.3)	0.2	2.2 (1.2–3.8)	0.006	4.9 (1.6–15.3)	0.006
	Apple Juice	2.6 (1.6–4.3)	0.0001	0.7 (0.1–5.1)	0.7	3.7 (1.7–8.4)	0.001	3.1 (1.7–5.6)	0.0002
LES relaxation reflex	Air	3.6 (1.3–10.1)	0.01	1.5 (0.6–3.3)	0.4	1.3 (0.9–1.9)	0.2	1.3 (1.0–1.7)	0.04
	Water	12.0 (0.1–1096.8)	0.3	2.6 (0.6–12.2)	0.2	1.3 (0.7–2.4)	0.4	1.7 (1.1–2.8)	0.02
	Apple Juice	12.9 (1.5–108.8)	0.02	3.3 (0.5–22.2)	0.2	1.2 (0.7–2.3)	0.5	2.7 (1.3–5.3)	0.006
Peristaltic reflex	Air	30.2 (0.7–1386.3)	0.08	1.5 (0.7–3.3)	0.3	1.1 (0.8–1.6)*	0.5	3.4 (1.4–8.2)*	0.006
	Water	0.6 (0.1–3.1)	0.6	1.7 (0.1–22.7)	0.7	1.9 (0.9–4.0)	0.1	2.8 (1.6–4.9)	0.0002
	Apple Juice	1.1 (0.5–2.5)*	0.8	190.7 (5.5–6578.4)*	0.003	1.7 (0.9–3.2)	0.1	2.6 (1.3–5.3)	0.006

Values are expressed as odds ratio and 95% confidence intervals;

^*P < 0.05, maturational difference between time 1 and time 2.

Multiple logistic regression and GEE methods were applied to evaluate the relationship between the response (binary outcome of the three specific reflexes, i.e., UES contractile reflex, LES relaxation reflex, Peristaltic reflex) and the independent variables (maturational stages, sleep stages, media, and graded volume). Significant odds ratio indicate a positive correlation between volume increments and the predictive reflex. For example, with a unit increase in dose volume of air, the occurrence of UES contractile reflex with awake stage at time-1 study was 1.2 times versus 3.5 times at time-2 study, and the dose-response relationship is advanced with maturation.