TABLE 4. Literature Review of Key Outcome Domainsa.

Study Authors	Behaviors
	Sucking	Breathing	Feeding	Competence/Problems	Arousal	Sleeping/Sedated	Resting (Drowsy)	Fussing/Crying
Kron et al10 (1976)	X		X
LaGasse et al11 (2003)	X			X	X
Gewolb et al18 (2004)	X	X	X
Maguire et al8 (2015)			X		X	X	X	X

^aDescription of study domains: (1) sucking characteristics included (a) sucking rate (sucks per minute), (b) average suck duration (seconds per suck), (c) percentage time during the experiment that the infant is actively sucking (suck time/total time x 100), and (d) sucking burst (interburst interval, proportion sucking, and burst per minute); (2) breathing characteristics included swallow-breath and breath-breath intervals; (3) feeding characteristics included feeding, nutrient consumption, and swallowing; (4) competence characteristics included the appropriateness of state for feeding; and (5) arousal characteristics include the predominant behavioral state.