To intervene or not to intervene : effects of behavioural sleep interventions on infant attachment quality.
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
This study aimed to explore the relationship between infant sleep disturbance (ISD) and attachment quality in 1-year-old infants, within two groups of families differing in their help-seeking preferences; and to investigate the effects of behavioural sleep interventions (BSI) on infant attachment and family wellbeing. A mixed design of pre-/ post-test prospective longitudinal and single-case design with a multiple baseline across participants was employed, with four data collection phases over 4 to 6 months. Twenty four participants (age range = 11-16 mo., M = 13.16 mo., SD =1.32; 58% boys) completed the first phase and 18 participants completed all four phases of the study (n = 10 completed a BSI, n = 8 provided comparison data). Attachment was measured via the Strange Situation Procedure at baseline and follow-up. Sleep patterns were measured continuously while the severity of sleep problems, infant perceived and observed negative emotionality, parental cognitions about infant sleep, nighttime and daytime behaviours, and parental wellbeing were measured once at each phase. The standard multiple regression analyses with n =24 revealed that ISD and attachment variables were not associated at baseline. ISD was associated with parental nighttime involvement, feeding beliefs, nighttime limit setting difficulties and less infant negative emotionality. Intervention (n = 13) and comparison (n = 11) groups at baseline were different in their cosleeping practices and the onset age of ISD. A Discriminant Function Analysis indicated that parents who wanted to receive a BSI were more likely to set limits at night-time and their infants cried less during a short separation. Visual analysis of time-series data from all phases indicated that after receiving a BSI 80% of the intervention infants no longer had ISD and comparison infants continued having ISD with only small improvements. Analysis of point-per-phase data using the modified Brinley Plots showed that BSIs did not cause any harm to the infant, parent, and their attachment relationship and improved the overall family wellbeing. A gradual improvement in infants’ sleep in the comparison group was predicted by having consistent secure attachment. Overall, ISD was not found to be related to infant attachment quality and treatment outcomes indicated positive results in favour of intervening with ISD.