“…Preterm infants receiving this developmental care show increases in the amount of quiet sleep (Bertelle, Mabin, Adrien, & Sizun, 2005); sucking, oral sucrose feeding, and facilitated tucking showed greater occurrences of quiet sleep and fewer occurrences of fussing and crying during heelstick procedures than those receiving routine care (Liaw et al, 2013). Other factors associated with preterm infant sleep during hospitalization include postmenstrual age (PMA; Holditch-Davis, 2010), gender (Ledergerber, Jost, Schulzke, Weber, & Datta, 2015;Tikotzky et al, 2015), the pain caused by intrusive procedures (Bonan et al, 2015), illness severity (Lan, Yin, Chen, Chang, & Liaw, 2017), and feeding methods (breast or formula feeding; Huang et al, 2016;Rudzik & Ball, 2016). These variables also should be considered when assessing interventions for improving preterm infants' sleep.…”