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Effects on infants of an intervention aimed at reducing night waking and signaling in 6-to-12 month old… Hall, Wendy A.; Saunders, R. A.; Clauson, Marion Isobelle; Carty, E. M.; Janssen, P. A. 2006

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Infant Sleep Intervention  1  Effects on Infants of an Intervention Aimed at Reducing Night Waking and Signaling in 6-to12Month Old Infants  W.A. Hall, RN, PhD Associate Professor, University of British Columbia School of Nursing T. 201, 2211 Westbrook Mall Vancouver, British Columbia, Canada, V6T 2B5 Telephone: 1(604)822-7447 Fax: 1(604)822-7466 Email: hall@nursing.ubc.ca R.A. Saunders, M.R.C.P. (UK), F.R.C.P. (C) Clinical Associate Professor, Faculty of Medicine, University of British Columbia M. Clauson, RN, MSN Senior Instructor, University of British Columbia School of Nursing E.M. Carty, RN, M.N. Director, Division of Midwifery, Department of Family Practice, University of British Columbia P.A. Janssen, RN, PhD Assistant Professor, Department of Health Care and Epidemiology, Faculty of Medicine, University of British Columbia  Acknowledgements: Funding from the British Columbia Medical Services Foundation grant # BCM02-4007; contributions by our study coordinator, Cheryl Segaric, research assistant, Ann Laing, and the study families; and thoughtful critiques by Dr. Owens, Editor of the Journal, and our reviewers. This paper was presented at the 2nd Canadian Sleep Society Congress.  Infant Sleep Intervention  2  Abstract This quasi-experimental one group pre and post-test pilot study evaluated an intervention aimed at reducing night waking and signaling for infants between 6 and 12 months of age. Thirty-nine healthy infants and their parents were recruited. Thirty-five infants completed the intervention and data collection. Both parents participated in a group teaching session with telephone followup for 2 weeks. Actigraphy and sleep diary data were collected at baseline and 6 and 16 weeks post-intervention. We hypothesized a decrease in length and number of infant waking and crying periods and an increase in longest night sleep and nap time. Following the intervention, infants had significantly reduced length of night crying and number of wakes and longer night sleep periods. The intervention warrants evaluation with a randomized controlled design.  This is an Author's Accepted Manuscript of an article published in Behavioral Sleep Medicine, 4(4), 242-261. 2006. Copyright Taylor & Francis, available online at http://www.tandfonline.com/10.1207/s15402010bsm0404_4  Infant Sleep Intervention  3  A common pediatric disturbance for which parents seek advice is waking and crying repeatedly at night after 6 months of age (Howard & Wong, 2001). Between 15 to 35% of all children between 6 months and 5 years of age show some type of sleep disturbance (Thunström, 2000). Most pediatric sleep problems are behaviorally based; obstructive sleep apnea is rare in infants, represents only 1 to 2% of sleep problems, and peaks in 2- to 6-year-olds (Halbower & Marcus, 2003; Howard & Wong). In infants, timing of sleep and waking is regulated by a circadian pacemaker (about 24hour), which is entrained to the light-dark cycle; a homeostatic process in which a need for sleep accumulates during waking (sleep pressure) and is satisfied during sleep; and ultradian cycling (less than 24-hour) between active sleep (REM) and quiet sleep (non-REM) within a given sleep episode (Peirano, Algarín, & Uauy, 2003). Longest sleep time at night rather than total sleep time is a sensitive indicator of sleep-wake organization or the ability for an infant to consolidate sleep and develop diurnal patterns (Anders & Keener, 1985). Long sleep periods lasting up to 6 hours at about 6 weeks after birth gradually lengthen to 8 or 9 hours and shift into the night; by 6 months of age the longest sleep period is about 50% of total sleep time (de Weerd & van den Bossche, 2003). The circadian cycle begins to emerge at 6 weeks of age and a diurnal pattern of sleep and wakefulness is established by 12 weeks of age, with daytime sleep consolidated into well defined naps (Peirano et al.). Two prevailing well defined sleep states in infants are REM sleep or Active sleep and non-REM Sleep or Quiet Sleep (de Weerd & van den Bossche, 2003). Quiet and active sleep change to non-REM and REM sleep, respectively, over the course of infancy. By three months of age, sleep onset REM periods begin to be replaced by non-REM sleep onset periods and, although REM periods continue to recur in 50-60 minute periods, the amount of REM sleep in each cycle shifts so that REM predominates in the later sleep cycles and non-REM Stage 4 sleep  Infant Sleep Intervention  4  predominates during earlier cycles (Anders & Taylor, 1994). The proportion of REM (active sleep) decreases to 25% by 6 months of age (de Weerd & van den Bossche). The REM-nonREM ultradian periodicity of 90 minutes is not observed until adolescence (Anders & Taylor). Study of spontaneous awakenings out of sleep in the first year of life has revealed a decrease in the number of awakenings out of REM sleep and a shortening of wakefulness after awakenings out of quiet (non-REM) sleep (Ficca, Fagioli, Giganti, & Salzarulo, 1999). In Sleep Onset Association Disorder (SOAD) infants learn to fall asleep only with certain conditions, such as being fed, and do not learn to self-soothe; an infant who experiences brief night arousals that occur at the end of each sleep cycle is unable to return to sleep without parents providing the conditions associated with falling asleep (Owens, 2004). Factors that have been associated with SOAD can include feeding infants back to sleep at night, co-sleeping (infant sleeping in the parents’ bed), and parental presence with sleep onset (Thunström, 1999; Touchette et al., 2005; Zuckerman, Stevenson, & Bailey, 1987). Ramos (2003) has made a distinction between reactive co-sleeping, where parents may respond to sleep problems after unsuccessful ‘sleep training’ by co-sleeping, and intentional cosleeping, where parents choose to co-sleep because they believe it is best for their infants. Reactive co-sleeping has been associated with sleep disturbances (Ramos). Infants’ night waking and related sleep problems have also been associated with difficult temperaments; however, the direction of the relationship has not been substantiated (Atkinson, Vetere, & Grayson, 1995; Halpern, Anders, Coll, & Hua, 1994; Sadeh, 2004). Despite numerous correlation-based studies, the causes and risk factors for pediatric sleep disturbances are not well specified (France & Blampied, 2004). While some infants grow out of night waking, between 25 to 45% continue to exhibit problems with night waking at 1 (Jenkins, Owen, Bax, & Hart, 1984) and 3 years of age  Infant Sleep Intervention  5  (Zuckerman et al., 1987). Sleep problems first presenting in infancy can persist into the preschool and school-aged years and become chronic (Mindell, Kuhn, Lewin, Meltzer, Sadeh, & Owens, in press). Children with sleep problems in infancy are more likely to have instances of night waking as preschoolers than those who did not have reported sleep problems in infancy (Thome & Skulladottir, 2005). Behavioral and emotional problems in children have also been associated with sleep problems (Dahl, 1998). In a longitudinal study, preschool children who slept less than 9 hours were more likely to be inattentive and unable to concentrate and to demonstrate aggressive behavior by age 4 and a half than children who had slept more than 10 hours (Touchette, Petit, Paquet, Tremblay, & Montplaisir, 2004). Internalizing (withdrawn and anxious) and externalizing (aggressive and overactive) behavior and somatic problem scores have been significantly higher for preschool children whose infant sleep problems persisted than for those whose sleep problems were resolved (Lam, Hiscock, & Wake, 2003). Toddlers with sleep problems have demonstrated reduced approachability, adaptability, and persistence at tasks (Scher, Epstein, Sadeh, Tirosh, & Lavie, 1992). In longitudinal studies, sleep difficulties as an infant have been associated with adverse clinical and behavioral indicators at 5 and 10 years of age, specifically more health care visits and sleeping problems at 5, and more hospital visits and temper tantrums at 10 (Pollock, 1992). None of these associations can be interpreted as causal. British researchers conducted analyses to estimate costs to the National Health Service directly related to infant crying and sleeping problems. When they compared groups of children up to 12 weeks age that were exposed to either behavioral interventions, written information, or regular services, they concluded that costs of contacts with health care professionals typically incurred by regular service groups up to 12 weeks post birth were in excess of 1 million dollars (USD) annually, not including costs from indirect influences (Morris, St. James-Roberts, Sleep,  Infant Sleep Intervention  6  & Gillham, 2001). Treating children with behavioral interventions incurred small additional costs but produced a significant benefit by 12 weeks of age, which was not the case for the written intervention. Given the far-reaching effects of pediatric sleep problems, evaluation of effective treatment approaches is crucial. Treatment of sleep problems through behavior modification has decreased nighttime waking (Minde, Faucon, & Falkner, 1994), without negative side effects (Adams & Rickert, 1989; Ferber, 1985; Ramchandi, Wiggs, Webb & Stores, 2000). Kuhn and Elliott (2003) have characterized extinction and graduated extinction as well-established interventions for frequent night waking. Extinction, otherwise known as systematic ignoring or letting the infant cry, has been described as the fastest behavioral approach for eliminating settling difficulties and night waking (France, Henderson, & Hudson, 1996; Reid, Walter, & O’Leary, 1999); however, parents have been reluctant to use the approach as they find it difficult to listen to their infants cry without intervening (Ferber; Minde et al; Ramchandi et al.; Reid et al.). Although graduated extinction takes longer to obtain an effect, because parents fade successive checks over time, it permits parents to withdraw the reinforcing behavior that supports the sleep problem without abandoning the infant at night (Finn Davis, Parker, & Montgomery, 2004; France et al.). Both extinction and graduated extinction focus on managing night waking episodes without attending to day time routines or the environment. Regular daytime sleep patterns are also important to nighttime sleeping because overtired infants have more interrupted sleep at night (Child and Youth Health, 1994). Routines can help to settle children, particularly temperamentally irregular infants who do not fall asleep naturally at the same time each night (Howard & Wong, 2001); however, many interventions have not included daytime scheduling. Stimulus control, which involves pre-bed routines, regular time of day and a fixed sleeping place have been provided to improve infant settling (Owens, France, &  Infant Sleep Intervention  7  Wiggs, 1999). Standardized bedtime routines have been included in many studies; however, they have not been evaluated as a stand-alone intervention (Mindell et al., in press) Ramchandi and colleagues (2000) indicated, because there was no evidence to support one type of sleep intervention over others, studies should evaluate a variety of treatments. Owens, Palermo, and Rosen (2002) highlighted the need for combined behavioral strategies, rather than focusing on a single approach in pediatric clinical practice, because individualized programs, which have allowed some tailoring to parents’ preferences, have been consistently associated with high success rates in clinical research. Parental compliance issues associated with some approaches such as extinction have significantly limited positive outcomes. Combining interventions permits parents to emphasize strategies based on their assessment of the problem and reinforces consistent approaches to infants’ behavioral sleep difficulties over the whole day. Although multi-faceted interventions do not permit the analysis of the efficacy of individual interventions, they have high ecological validity, because clinicians are more likely to combine strategies when working with parents (Mindell et al., in press). In response to some parents’ refusal to use systematic ignoring, a number of Australian agencies have introduced controlled comforting (graduated extinction), daytime and bedtime routines, and information about sleep to assist parents resolve their infants’ behavioral sleep problems (Ngala, 2004; Tweddle Child & Family Health Service, 1998). A randomized trial of a similar intervention, offered in three private consultations, was carried out in Australia with infant sleep changes based on maternal report (Hiscock & Wake, 2002).The intervention group had resolution of sleep problems in 53 out of 76 children versus a control group resolution for 36 out 76 infants.  Infant Sleep Intervention  8  Research Design and Objectives The pilot study used a quasi-experimental one-group pre and post-test design following an intervention. The objectives were to examine changes in infants’ sleep patterns and behavior following the intervention and to determine the feasibility of measurement procedures. We hypothesized: 1) a decrease in length and number of awake and crying periods at night, 2) an increase in longest sleep time at night, and 3) an increase in length of nap times. Sample Thirty-nine infants, whose parents were calling for assistance with infant behavioral sleep problems, were recruited through the Newborn Hotline in a large Western Canadian city. Inclusion criteria comprised infants who were healthy, living in two-parent families, in a home with a working telephone, and waking 2 or more times per night or for more than 20 minutes for 4 nights per week over 2 or more months. This definition was developed from Richman’s (1981) and Carey’s (1974) criteria. Infants were excluded who were multiples, receiving medication for sleep problems, being treated for respiratory problems, being treated for neurological problems or diagnosed with mental retardation. Parents documented their ethnicity, education and income levels, feeding activities, co-sleeping activities, numbers of children, and length of time as a couple. Those variables were of interest to accurately describe the sample and examine changes in co-sleeping and night feeding, because they have been associated with sleep problems. The parents constituted a multi-ethnic, middle class, well-educated group. The number of infants decreased from baseline to time one, because we had 4 families drop out of the study for reasons of marital breakdown, extended family objections to the intervention, and resolution of the problem before the intervention. There were no demographic differences in the drop-outs. The infants were 50% male and female ranging from 6 months to 10.5 months. Parents were in  Infant Sleep Intervention  9  average family income brackets with college education and mixed ethnicity: Canadian, European, Chinese and Aboriginal. The parents (N=78) ranged in age from 27 to 53 years (M = 35.2) and reported being with their partners between 13 and 156 months (M = 67.5 months or 5.6 years). The majority of couples (84.8%) had one child. Education ranged from 9 to 26 years, with 48.8% of parents completing between 17-20 years of education (M = 16.7). Sixty-one percent of parents identified themselves as Canadian. Chinese parents constituted 15% of the sample and South Asian parents constituted 11%. Family income ranged between $10,000 to greater than $110,000 with the majority reporting a family income between $60,000 and $89,000 at each time point. The infants’ demographic characteristics are summarized in Table One. Of 105 days of sleep diary and actigraphy data, which included 2 to 3 naps per day, there were 22 episodes where infants napped in a car or a stroller. Fifteen infants had teething episodes that were equally distributed over times 1, 2, and 3. None of the families reported using motion during the night to put infants to sleep. Eight infants developed colds during the course of the 105 days of data collection: 2 infants at time 1, 5 infants at time 2, and 1 infant at time 3. It was not feasible to change the timing of the measures. Six actigraphs were purchased for the study and the groups were staggered to rotate the instruments. Staggering groups created situations where, following a week of baseline data for a new group, there was a week of time 2 data collection for a different group, followed by time 3 data collection for a third group. The Intervention Protocol Each infant and his/her parents were assigned to an intervention group to a maximum of 6 families per group. There was a total of 7 groups (3 groups of 5 and 4 groups of 6). All groups received the same intervention. Because this was a pilot study to test the feasibility of the intervention and measurement, a control group was not used. The intervention required both  Infant Sleep Intervention  10  parents to be involved in a mandatory 2-hour teaching session, complete charts, and receive telephone support. Parents were reimbursed for parking and childcare expenses. The teaching session provided information about a) normal infant sleep, b) negative sleep associations, c) bedtime routines, d) organized daytime schedules and naps, e) controlled comforting, and f) parents looking after themselves. With controlled comforting (graduated extinction), parents were provided with information about responding to their infants’ crying during sleep periods by comforting their infants in their cots up to a maximum of 10 minutes, with increasingly longer time intervals out of the room from 2 minutes to 10 minutes and to fade their response over time. Two videos were shown; one that captured normal infant sleep and one that presented a couple’s perceptions about living with and trying to resolve an infant sleep problem. The information session incorporated a question period for parents’ specific concerns. Parents were requested to use the content (reducing negative sleep associations, instituting bedtime routines, organizing daytime schedules and naps, and using controlled comforting) to assist their infants directly after the teaching session. They were encouraged to complete the feeding-sleeping charts (Figure 1) and controlled comforting charts (Figure 2) that were provided. The charts helped parents document their infants’ routines during the day and the controlled comforting they offered at night. These charts were an important element of the intervention because they could indicate subtle improvements in infants’ patterns. Feed-sleep charts can reinforce treatment and increase parents’ awareness of children’s patterns (Seymour, Bayfield, Brock & During, 1983). Controlled comforting charts highlight subtle improvements in waking and crying episodes and encourage parents to trust their observations (Largo & Hunziker, 1984). Following the teaching session, the study coordinator called to offer telephone support twice weekly for 2 weeks. The short time frame for telephone follow-up was warranted, because  Infant Sleep Intervention  11  investigators have reported significant decreases in waking time as early as one week after initiating interventions (Sadeh, 1994; Seymour, Brock, During, & Poole, 1989). During the telephone calls, the parent most involved in the intervention described strategies, progress, any difficulties, and asked questions about refining approaches. The coordinator offered support and encouragement. She clarified questions about the content but did not offer additional suggestions beyond those provided in the protocol. Calls varied in length from 10 to 60 minutes (M = 20 minutes). Most parents appreciated the coordinator’s support; some expressed disappointment that the calls were not continued past 2 weeks. Method Participants were visited one week prior to the intervention by a graduate research assistant who obtained signed consent and baseline data (time 1). At 6 (time 2) and 16 weeks (time 3) after the teaching session, the baseline measures (infant demographic, sleep diaries, and actigraphy) were repeated for all participants. At the three time points, parents applied to their infant an actigraph that was worn 24 hours a day, except for baths, over three days. Actigraphs collect continuous, objective sleep/rest/activity data of which parents are unaware (Sadeh, Hauri, Kripke, & Lavie, 1995). Simultaneously, parents completed sleep diaries that documented their infants’ sleep, waking and crying episodes, and feeding 24 hours a day over 3 days. The sleep diaries provided space for recording dates, bedtimes, rising times, each waking time, length of wake time, if crying was involved, parents’ responses to settle their infants, any infant illnesses, and daytime napping and feeding schedules. To determine whether there was a decrease in length and number of awake and crying periods, an increase in longest sleep time, and an increase in nap time, the actigraphic data and sleep diary data were either averaged over the three days (number of infant crying episodes,  Infant Sleep Intervention  12  length of infant crying episodes, and length of longest night sleep period) or totaled over the 3 days (total nap time and total sleep time) in order to compare the infants at each time point. Because co-sleeping has been associated with infant sleep problems, McNemar’s test was used to compare the infants on presence of co-sleeping. It was also used to compare breastfeeding rates at times 1, 2 and 3. On number and length of night crying episodes, longest sleep period, total sleep time and total nap time, paired-sample t tests were used to compare the groups from time 1 to time 2 and from time 2 to time 3. To decrease the risk of a type 1 error, Bonferonni’s correction was used where the p value accepted as significant was divided by the number of comparisons (Field, 2000), in this case, 7 comparisons at times 2 and 3. Thus, in all statistical analyses, two-tailed p = 0.007 was accepted as the level of significance. Correlations were used to examine the relationships between actigraphic data and sleep diary data. Effect sizes, using Cohen’s formula, were calculated only for the variables that were significant at p < 0.007, except for average length of crying time with significance at p = 0.02 and number of sleep diary wakes with significance at p = .01. In order to determine possible differences that could have resulted due to differences in age and development, General Linear Model Analysis was run to compare the infants by age groups (5 to 9 months) and (9.5 to 12 months) on changes in longest sleep periods by sleep diary and actigraphic data. Wilcoxon’s Signed Ranks Test was undertaken to examine change in average longest sleep for infants. Pearson’s r was used to examine correlations among sleep diary and actigraphic data. Results Following the intervention, there was a significant increase in the average duration of longest sleep on sleep diary and actigraphy data, and a significant decrease in the average number of wakes on actigraphy and diary data and duration of total night crying based on parents’ sleep diary data (Table 2). At time 2, there was no significant increase in infants’ total  Infant Sleep Intervention  13  nap time, or total sleep time, based on the sleep diary data. The Wilcoxon Signed Ranks Test compared the average longest night sleep time from sleep diary and actigraphy data at time 1 and 2. For sleep diary data, twenty-seven of the 34 children changed in a positive direction; only 7 changed in a negative direction (Z = -3.26, asymp. significance = .001). Of the seven who decreased their longest sleep time one infant was being feed to sleep and fed during the night back to sleep every 3 hours and 5 parents reported their infants were teething (n = 3) or had a cold (n = 2) over the 3 day data collection period. For the actigraphy data, 16 of 23 infants changed in a positive direction and 7 changed in a negative direction (Z = -2.677, asymp. significance = .007). The group of infants whose actigraphic data showed a decrease at time 2 included 3 of the 7 infants who had a decrease based on the diary data. The remaining 4 infants had diary times that increased. Two actigraphy recordings were missing for two infants who decreased their longest sleep period on sleep diary data. To determine whether the changes in the variables persisted, comparisons were made between 6 and 16 weeks post-intervention. The changes in average duration of longest sleep and night crying and number of night crying episodes remained stable at time 3, with no significant difference between 6 and 16 weeks. There were no significant differences in length or number of actigraphic wakes or diary wakes during the night from time 2 to time 3. There was a significant decrease in the length of nap times from time 2 to time 3, which would be expected based on the children’s increasing ages and different developmental stages. There was also a decrease in total sleep time, based on sleep diary data from time 2 to time 3 (Table 2). At time 1, 81.8% of the mothers reported that they were breastfeeding. Although the proportion of infants breastfeeding at time 2 (70%), was less than at time 1, the difference was not statistically significant (McNemar’s test, p = .08 from time 1 to 2). The decreased rate of breastfeeding between time 2 (70%) and time 3 (54%) approached significance (McNemar’s test,  Infant Sleep Intervention  14  p = .04). At time 3, 57% of the infants were between the ages of 11.5 and 16 months and 72% of their parents were also working outside the home. Because we were discouraging reactive cosleeping in 6-to 12-month old infants, concerns had been raised by breastfeeding advocates that the intervention would interfere with breastfeeding. The breastfeeding rate of British Columbian mothers at 6 months post birth is reported at 55% (Statistics Canada, 2005); therefore, we concluded that breastfeeding was not dramatically reduced following the intervention. Co-sleeping was defined as the child sleeping in bed with the parent or parents for all or part of the night. In this sample, all parents reported that co-sleeping was reactive rather than intentional. Following the intervention, co-sleeping changed significantly from 70% yes at time 1 to 74% no at time 2 (McNemar’s test, p <.000). Although there was a slight increase reported in co-sleeping from time 2 (25.7% yes) to time 3 (26.1 yes), this change was not statistically significant (McNemar’s test, p = 1). Co-sleeping occurred fewer times per week from time 1 to time 3. Using the repeated measures, with the children divided by age groups (5 to 9 months) and (9.5 to 12 months) means for the sleep diary and actigraphic data were compared for longest sleep periods over the three time points. Mauchly’s test was not significant showing that the condition of sphericity was met for the actigraphy data (W (2, 14) = .669, p = .109) and for the sleep diary data (W (2, 25) = .81, p = .1). In other words the variances of the differences between levels were not significantly different. On the basis of actigraphy data, there were no significant differences within subjects by age (F (1, 12) = 2.73, p = .124), but there was a significant difference for sleep by time (F (1, 12) = 11.41, p = .005). For the sleep diary data, F was not significant by age (F (1, 23) = 1.67, p = .2), but was significant by time (F (1, 23) = 16.7, p = .000). In both cases, the older age group’s mean longest sleep time increased both from time 1 to  Infant Sleep Intervention  15  time 2 and from time 2 to time 3. The younger age group’s mean longest sleep time increased from time 1 to time 2 but was essentially the same at time 3. The actigraphs provided by the manufacturers did not include the Sadeh algorithm for analysis of infant data (Sadeh et al., 1995). A co-investigator examined the utility of the actigraph settings by doing 5 test runs using both Zero Crossing (ZCM) and Lo-PIM (Proportional Integral Mode) settings simultaneously with two separate actigraphs attached on the same limb strap. Both the settings were equivalent in term of movement detection, recording the same 1-minute epochs as sleep or wake within 1% or better but the Lo-PIM provided more detail. The Lo-PIM setting, which did not permit the use of the Sadeh algorithm, was selected. The only significant difference between the UCSD-PIM and the Sadeh-ZCM algorithm was in the number of epochs and their weighting before and after the index epoch which the algorithm used to ‘rescore’ the index epoch as sleep or wake. Each record was manually scored and the difference was removed. Epochs scored by raw automatic scoring as wake but lasting less than 5 minutes were rescored as sleep. After the manual scoring, the automated statistical analysis was run for final results. Only corrected actigraphy data were used for statistical analyses. The correlations between actigraphic and sleep diary data for number of wakes and longest sleep time were examined. From the sleep diaries, number of wakes was equated with the infants signaling the parents with crying because that was how the parents knew their children were awake. The correlations between the sleep diaries and actigraphic average numbers of wakes were high and significant at time 1 (r = .86, n = 32, p = .000) and time two (r = .58, n = 28, p = .001). At time three, the correlation between the actigraphic and sleep diary average numbers of wakes was not significant (r = .30, n = 30, p = .10). For longest sleep time, there was a significant correlation between the actigraphy and diary data at time 1 (r = .87, n = 32, p = .000) and the p value approached significance at time 2 (r = .47, n = 28, p = .01). At time 3, the  Infant Sleep Intervention  16  correlation between the actigraphy and sleep diary longest sleep time also approached significance (r = .358, n = 29, p = .056). For average length of actigraphic wakes and night crying, there were significant correlations between the actigraphy and the diary data at times 1 (r = .64, n = 32, p = .000) and 2 (r = .63, n = 28, p = .000). At time 3, the correlation for average length of actigraphic wakes and night crying was not significant (r = .25, n = 34, p = .19). We assume that the children were not signaling when they were awake. Discussion In summary, following a behavioral intervention for infant sleep problems, we found a significant positive decrease in total night crying by sleep diary and average number of wakes by actigraphy. There was also a significant increase in longest sleep period by actigraphy and sleep diary. The average number of wakes and length of night crying by sleep diary decreased but the decreases were not significant (p = .02 and .01), because we used the Bonferroni correction, with p = .007. There was no significant increase in nap time or total sleep time. The study findings were limited by the number and characteristics of the participants. Consequently, generalization of the study findings is limited to other populations who meet the inclusion and exclusion criteria specified. The study design did not include the use of a control group. The control group was not included because the investigators (a) planned the study as a pilot, (b) recruited a group already self-selected by calling the hotline, (c) and deemed non-intervention for 4 months unacceptable to parents, and contrary to community service providers’ contract. Without the use of a control group, we cannot conclude that the study findings are the result of the intervention, as opposed to other extraneous variable(s), or a combination of both. There could have been developmental changes in the infants’ sleep patterns that influenced the study findings. Despite these limitations, the variety of analyses undertaken and results strongly support the efficacy of the  Infant Sleep Intervention  17  intervention. On the basis of the paired t-tests, there was a large effect size for decreased numbers of infant wakes by actigraphy during the night, increased longest sleep period by actigraphy and sleep diary, and total night crying by sleep diary. There were moderate effect sizes for decreased total night crying, number of wakes, and average length of night crying, and increased longest sleep period by sleep diary. Co-sleeping (in parents’ beds) was significantly reduced. We discouraged co-sleeping because, universally, the parents in our study indicated that they preferred not to co-sleep with their infants and had done so out of desperation to increase their own sleep at night; most parents indicated co-sleeping had failed to be effective. In cases where infants are light sleepers, cosleeping may actually serve to disrupt their nighttime sleep. The parents in our study were using reactive co-sleeping, which Ramos (2003) has suggested can be associated with reduced parental satisfaction with sleeping arrangements and with parents who reacted early in the first 12 months of an infant’s life to night waking. The improvement in most of the infants’ sleep in association with the reduction in co-sleeping is congruent with work that has linked co-sleeping to infant sleep problems (St. James-Roberts, Sleep, Morris, Owen, & Gillham, 2001; Thunström, 1999: Touchette et al., 2005); however, as Ramos points out, family sleeping arrangements and their consequences are too complex to be explained only by single variables. The coordinator noted in her field notes that, after completing the charts, many parents were surprised to find an absence of routines in their infants’ lives. They described improvements in their children after routines were established. These findings fit with Seymour et al.’s (1983) assertions that it is helpful to increase parents’ awareness of their infants’ patterns or lack of patterns. Our intervention also used controlled comforting in combination with other treatment components. In a number of reviews, graduated extinction (controlled comforting) has been  Infant Sleep Intervention  18  strongly supported as an effective intervention for behavioral sleep problems (Meltzer & Mindell, 2004; Mindell et al., in press; Owens et al., 1999); however, Mindell et al. have indicated that most studies have involved multi-component treatment packages. We also emphasized establishing daytime schedules and bedtime routines and reducing negative sleep associations that included rocking or feeding infants to sleep and feeding infants who were between 6 and 12 months of age every 2 to 3 hours with waking at night. We made those suggestions while emphasizing the importance of breastfeeding for a long as possible. A comparison with the literature incorporating graduated extinction for infants with sleep problems revealed studies that effectively reduced infant sleep problems and compared graduated extinction with other methods (Sadeh, 1994), combined graduated extinction with routines (Pritchard & Appleton, 1988; Thunström, 2000), or used two-step graduated extinction (Eckerberg, 2002). Hiscock and Wake (2002) provided the most similar treatment to our study because they incorporated controlled comforting and information about normal sleep patterns, bedtime routines and naps, and negative sleep associations such as overnight feeding; however, their study was a randomized controlled trial and involved 3 private consultations with sleep management plans. Many sleep interventions have involved extensive counseling sessions on a one-to-one basis. Our intervention was of short duration and capitalized on parental support in a group class. In field notes, parents indicated that the group setting helped to ‘normalize’ their perceptions of infant sleep problems and enabled them to feel that they were not alone. Owens et al. (1999) found no publications of empirical evaluations of group interventions. A literature search of Pub Med, Psych Info, Web of Science, and Medline revealed no publications since 1999 describing a group intervention. English and Scottish investigators have described using group approaches to  Infant Sleep Intervention  19  pre-schoolers’ behavioral sleep problems that spanned 6 to 7 weeks of meetings (Balfour, 1988; Carpenter, 1990; Szyndler & Bell, 1992). This study used actigraphic data. Actigraphic data are important because they can discriminate between sleep-disturbed (infant waking) and control children, with an assignment rate of 79% to 91% (Sadeh, Lavie, Scher, Tirosh, & Epstein, 1991) and have documented improvement in sleep following treatment (Sadeh, 1994). Infants who are unable to self-soothe usually vocalize when they fully awaken at night. In this study, the recorded number of nocturnal wakes and length of nocturnal wakes on the sleep diaries correlated well with the actigraphic data at time 1 and time 2. We surmise that the lack of significant correlations at time 3 represented waking that was documented by actigraphy but was not signaled to the parents, because the children settled themselves back to sleep. Because some research has indicated a decrease in the number of awakenings out of REM sleep and a shortening of wakefulness after awakenings out of quiet (non-REM) sleep (Ficca et al., 1999), it is possible that the duration of wakefulness out of sleep made signaling less likely. An alternative explanation is the effectiveness of the intervention for infants learn to put themselves back to sleep. The actigraphic and sleep diary data for longest sleep periods were significantly correlated at times 1 and 2, with time 3 approaching significance. The lack of significant correlation at time 3 could reflect our decision to use the Lo-Pim setting for actigraphy, as opposed to Zero Crossing with Sadeh’s infant algorithm analysis (Sadeh et al., 1995). The LoPim setting was intended to increase the sensitivity for movement detection during waking for young infants, but could have increased actigraphic sensitivity to REM ‘near-arousals’ or partial arousals between sleep cycles in older infants, thereby reducing the correlations for longest sleep between the actigraphic and sleep diary data. Alternatively, the divergence of correlation could  Infant Sleep Intervention  20  merely represent progressively increasing change in the parents’ perception of infants’ sleep quality over the 3 time points. The difficulty with demonstrating significant correlations at time 3 could be partly related to our loss of actigraphy data. Several actigraphs were returned to the manufacturing company for repair when they malfunctioned at time 3 (5 cases of missing data) and, despite training, there was operator error in initializing and downloading actigraphs (1 case of missing data at time 3). The Wilcoxon-signed rank test indicated that 7 pairs did not show an increase in longest sleep time, with three infants changing in the same direction for the actigraphy and the diary data. The actigraphic data were in the opposite direction for the other 4 comparisons with sleep diaries. That difference suggests that the actigraphs may have been recording REM ‘near-arousals’ or partial arousals between sleep cycles as waking episodes for older infants. Parental perception was also an important feature of the diaries that could have affected their recording of wake periods. The general linear modeling of repeated measures showed significant differences in longest sleep period changes on sleep diary data and actigraphy data over time but not by age group. That finding suggests that, following the intervention, there were similar changes in longest sleep pattern that were not attributable to developmental stage. This age group has also been treated by other investigators (Hiscock & Wake, 2002) and much larger age ranges have been treated by Eckerberg (2002), 4 months to 18 months, and Thunström (2000) who treated 6to 18-month-old-children. The 6-to 12-month-old infants in our study had much improved sleep following the intervention, with most infants moving in a positive direction for longest sleep by sleep diary and actigraphy. The lack of improvement in some infants suggests that those children did not ‘grow  Infant Sleep Intervention  21  out’ of the problem. Most changes stayed stable at time 3, which indicated changes in sleep patterns persisted for at least 4 months. The intervention in this study combined a number of approaches to infant behavioral sleep problems, as recommended by Owens et al. (2002). Parents commented that the group format was helpful and effective for their educational session. Time effective, group formats have not been empirically studied previously. The study was useful for illustrating potential technical problems associated with the design. The strength of the findings in this small sample of infants suggest that it is important to evaluate this time-effective, group intervention in community settings using a randomized controlled trial design.  Infant Sleep Intervention  22  References Adams, L. A., & Rickert, V. I. (1989). Reducing bedtime tantrums: Comparison between positive routines and graduated extinction. Pediatrics, 84(5), 756-761. Anders, T. F., & Keener, M. (1985). 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Services and programs proven to be effective in managing pediatric sleep disturbances and disorders, and their impact on the social and emotional development of children. In Tremblay, R. E., Barr, R. G., Peters, RDeV. (Eds.). Encyclopedia on Early Child Development [online]. Montreal, Quebec: Centre of Excellence for Early Childhood Development: 2004: 1-8. Retrieved on December 29, 2005 from http:www.excellenceearlychildhood.ca/documents/France-BlampiedANGxp.pdf. France, K. G., Henderson, J. M. T., & Hudson, S. M . (1996). A three-stage approach to treating the sleep problems of infants and young children. Child and Adolescent Psychiatry Clinics of North America, 5(3), 581-599. Halbower, A. C., & Marcus, C. L. (2003). Sleep disorders in children. Current Opinion in Pulmonary Medicine, 9, 471-476. Halpern, L. F., Anders, T. F., Coll, C. G., & Hua, J. (1994). Infant temperament: is there a relation to sleep-wake states and maternal nighttime behavior? Infant Behavior and Development, 17, 255263. Hiscock, H. & Wake, M. (2002). Randomized controlled trial of a behavioural infant sleep intervention to improve infant sleep and maternal mood. British Medical Journal, 324, 1062-1065. Howard, B .J., & Wong, J. (2001). Sleep Disorders. Pediatrics in Review, 22(10), 327-342. Jenkins, S., Owen, C., Bax, M., & Hart, H. (1984). Continuities of common behaviour problems in preschool children. Journal of Child Psychology and Psychiatry, 25(1), 75-89. Kuhn, B. R., & Elliott, A. J. (2003). Treatment efficacy in behavioral pediatric sleep medicine. Journal of Psychosomatic Research, 54(6), 587-597.  Infant Sleep Intervention  24  Lam, P., Hiscock, H., & Wake, M. (2003). Outcomes of infant sleep problems: A longitudinal study of sleep, behavior, and maternal well-being. Pediatrics, 111(3), e203-e207. Largo, R. H., & Hunziker, U. A. (1984). A developmental approach to the management of children with sleep problems in the first three years of life. European Journal of Pediatrics, 142, 170173. Meltzer, L. J., & Mindell, J. A. (2004). Nonpharmacologic treatments for pediatric sleeplessness. Pediatric Clinics of North America, 51, 135-151. Minde, K., Faucon, A., & Falkner, S. (1994). Sleep problems in Toddlers: Effects of treatment on their daytime behavior. Journal of the American Academy of Child and Adolescent Psychiatry, 33(8), 1114-1121. Mindell, J. A., Kuhn, B., Lewin, D. S., Meltzer, L. J., Sadeh, A., & Owens, J. A. (in press). Behavioral treatment of bedtime problems and night wakings in infants and young children. Sleep. Morris, S., St. James-Roberts, I., Sleep, J., & Gillham, P. (2001). Economic evaluation of strategies for managing crying and sleeping problems. Archives of Diseases in Childhood, 84, 15-19. Ngala (2004). Secrets of good sleepers. Perth, Western Australia, Ngala. Owens, J. (2004). Services and programs proven to be effective in managing infant/child sleeping disorders and their impact on the social and emotional development of young children (0-5). Encyclopedia on Early Childhood Development. . In Tremblay, R. E., Barr, R. G., Peters, RDeV. (Eds.). Encyclopedia on Early Child Development [online]. Montreal, Quebec: Centre of Excellence for Early Childhood Development: 2004: 1-8. Retrieved December 27, 2005 from http: www.excellence-earlychildhood.ca/documents/OwensJANGxp.pdf. Owens, J. L., France, K. G., & Wiggs, L. (1999). Behavioral and cognitive-behavioral interventions for sleep disorders in infants and children: A review. Sleep Medicine Review, 3(4), 281-302.  Infant Sleep Intervention  25  Owens, J. A., Palermo, T. M., & Rosen, C. L. (2002). Overview of current management of sleep disturbances in children: II - Behavioral Interventions. Current Therapeutic Research, 63(SB), B38-B52. Peirano, P., Algarín, C., & Uauy, R. (2003). Sleep-wake states and their regulatory mechanisms throughout early human development. Journal of Pediatrics, 143, S70-S79. Pollock, J. I. (1992). Predictors and long-term associations of reported sleeping difficulties in infancy. Journal of Reproductive and Infant Psychology, 10, 151-168. Pritchard, A., & Appleton, P. (1988). Management of sleep problems in pre-school children. Early Child Development and Care, 34, 227-240. Ramchandi, P., Wiggs, L., Webb, V., & Stores, G. (2000). A systematic review of treatments for settling problems and night waking in young children. British Medical Journal, 320, 209-13. Ramos, K. D. (2003). Intentional versus reactive cosleeping. Sleep Research Online, 5(4), 141-147. Retrieved December 28, 2005 from http://www.sro.org/2003/Ramos/141/. Reid, M. J., Walter, A. L., & O’Leary, S. G. (1999). Treatment of young children’s bedtime refusal and nighttime wakings: A comparison of “standard” and graduated ignoring procedures. Journal of Abnormal Child Psychiatry, 27(10), 5-16. Richman, N. (1981). A community survey of characteristics of one-to-two-year olds with sleep disruptions. Journal of the American Academy of Child Psychiatry, 20, 281-291. St. James-Roberts, I., Sleep, J., Morris, S., Owen, C., & Gillham, P. (2001). Use of a behavioural programme in the first 3 months to prevent infant crying and sleeping problems. Journal of Pediatric Child Health, 37, 289-297. Sadeh, A. (1994). Assessment of intervention for infant night waking:parental reports and activity-based home monitoring. Journal of Consulting and Clinical Psychology, 62(1), 63-68.  Infant Sleep Intervention  26  Sadeh, A . (2004). A brief screening questionnaire for infant sleep problems: Validation and findings for an internet sample. Pediatrics, 113(6), e570-e577. Sadeh, A., Hauri, P. J., Kripke, D. F., & Lavie, P. (1995). The role of actigraphy in the evaluation of sleep disorders. Sleep, 18(4), 288-302. Sadeh, A., Lavie, P., Scher, A., Tirosh, E., & Epstein, R. (1991). Actigraphic home-monitoring sleepdisturbed and control infants and young children: a new method for pediatric assessment of sleep-wake patterns. Pediatrics, 87, 494-499. Scher, A., Epstein, R., Sadeh, A., Tirosh, E., & Lavie, P. (1992). Toddlers’ sleep and temperament: Reporting bias or a valid link? A research note. Journal of Child Psychology and Psychiatry, 33(7), 1249-1254. Seymour, F. W., Bayfield, G., Brock, P., & During, M. (1983). Management of night-waking in young children. Australian Journal of Family Therapy, 4(4), 217-223. Seymour, F. W., Brock, P., During, M., & Poole, D. (1989). Reducing sleep disruptions in young children: Evaluation of therapist-guided and written information approaches: A brief report. Journal of Child Psychology and Psychiatry, 30(6), 913-918. Szyndler, J., & Bell, G. (1992). Are groups for parents of children with sleep problems effective? Health Visitor, 65(8), 277-279. Statistics Canada (2005). Breastfeeding practices, females aged 15 to 55 who had a baby in the previous five years, Canada, provinces, territories and peer groups 2003. Retrieved, September 21, 2006 from http://www.statcan.ca/english/freepub/82-221-XIE/2006001/tables/2178_03.pdf. Thome, M., & Skuladottir, A. (2005). Changes in sleep problems, parents’ distress and impact of sleep problems from infancy to preschool age for referred and unreferred children. Scandinavian Journal of the Caring Sciences, 19(2), 86-94.  Infant Sleep Intervention  27  Thunström, M. (1999). Severe sleep problems among infants: Family and infant characteristics. Ambulatory Child Health, 5, 27-41. Thunstöm, M. (2000). A 2.5 -year follow-up of infants treated for severe sleep problems. Ambulatory Child Health, 6, 225-235. Touchette, E., Petit, D., Paquet, J., Boivin, M., Japel, C.,Tremblay, R. E. et al. (2005). Factors associated with fragmented sleep at night across early childhood. 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Pediatrics, 80, 664-671.  Infant Sleep Intervention  28  Table 1  Infant Demographic and Sleeping Characteristics  Time 1 N = 39  Category Age in months  Breastfeeding  Co-sleeping  Time 3 N = 35  Descriptor  Percent  Descriptor  Percent  Descriptor  Percent  5-6  23.3  7 – 8.5  35.2  9 – 11  43.3  6.5 - 8  34.5  9 – 11  43.8  11.5 – 13.5  28.8  8.5 - 10  25.8  11.5 - 14  21  14 - 16  27.9  10.5 – 12.5  16.4  Range -7.5 Gender  Time 2 N = 35  Mean – 8.1  Range – 7 Mean – 9.9  Range – 7  Mean - 12  Male  44.4  Male  43.8%  Male  45.9%  Female  55.6  Female  56.2%  Female  54.1%  Yes  81.8  Yes  70  Yes  53.6  No  18.2  No  30  No  46.4  Yes  70.1  Yes  25.7  Yes  26.1  No  29.9  No  74.3  No  72.5  0  29.9  0  74.3  0  72.5  1-3  15.6  1-3  10  2-3  2.9  4-6  6.4  7  15.7  6-7  24.6  7-9  48.1  Co-Sleeping times per week  Range – 9  Mean - 4  Range – 7  Mean – 1.3  Range – 7  Mean – 1.7  Infant Sleep Intervention  29  Figure 1 Weekly Sleep-Feed-Wake Chart This chart helps you to have an accurate picture of your infant’s sleeping, feeding, and waking patterns. Completing this chart will help you to see the progress you are making with your infant in developing routines and patterns. To fill in the chart, draw a line through the square when your infant is sleeping. Leave the spaces when your infant is awake clear. When your infant has been fed, print an F in the box. 6 am  7 am  8 am  9 am  10 am  11 am  12 md  1 pm  2 pm  3 pm  4 pm  5 pm  6 pm  7 pm  8 pm  9 pm  10 pm  11 pm  12 mn  1 am  2 am  3 am  4 am  5 am  Mon. Tues. Wed. Thurs. Fri. Sat. Sun.  Indicates sleeping Indicates awake F  F  Indicates feed  Note. Adapted from Sleep Right, Sleep T ight, by Tweddle Child & Family Health Service, 1998, Melbourne, Victoria, Australia. Copyright 1998 by the Tweddle and Family Health Service. Adapted with permission.  Infant Sleep Intervention  30  Figure 2 Controlled Comforting Chart Filling in this chart over a 24 hour period will enable you to see how much time you are spending settling your infant at night and resettling your infant after waking. It will help you see that over a few days the time you spend settling your infant is decreasing and how your situation has improved. When you look at your progress, you will feel more confident about how you and your infant are getting on. 6 am  7 am  8 am  9 am  10 am  11 am  12 md  1 pm  2 pm  3 pm  4 pm  5 pm  6 pm  7 pm  8 pm  0 min 5 min 10 min 15 min 20 min 25 min 30 min 35 min 40 min 45 min 50 min 55 min 60 min Total minutes spent settling  Put a tick in the box for the number of minutes you have spent and add up the ticks over 24 hours. Note. Adapted from Sleep Right, Sleep Tight, by Tweddle Child & Family Health Service, 1998, Melbourne, Victoria, Australia. Copyright 1998 by the Tweddle and Family Health Service. Adapted with permission.  9 pm  10 pm  11 pm  12 mn  1 am  2 am  3 am  4 am  5 am  Infant Sleep Intervention  31  Table 2. Infant Outcome Variables Category  Actigraph Longest Sleep T1-T2  Time 1 (T1)  Time 2 (T2)  M  SD  M  SD  200.9  72.9  287.2  105.4  Actigraph Longest Sleep T2-T3 Length of actigraph wakes T1-T2  16.4  6.8  14.9  16.6 18.0  11.0  12.0  2.9  2.3  1.7 5.6  2.2  3.6  2.9 238.4  99.0  360.3  414.2 401.7  158.2  411.9  342.4 11.2  4.5  6.0  Total Sleeptime Diary T2-T3  4.7 2114.2  178.8  1.6  106.9  115.4  3.8  Total Night Crying Diary T2-T3 Total Sleeptime Diary T1-T2  1.3  130.3  Total Nap Time Diary T2-T3 Total Night Crying Diary T1-T2  10.0  119.8  Longest Sleep Diary T2-T3 Total Nap Time Diary T1-T2  10.3  2.1  Actigraphy wakes T2-T3 Longest Sleep Diary T1-T2  77.2  1.4  Diary wakes T2-T3 Actigraphy wakes T1-T2  SD  10.1 11.0  3.7  T1-T2 or T2-T3  9.3  Length Crying Time Diary T2-T3 Diary wakes T1-T2  M  290.8  Length of actigraph wakes T2-T3 Length Crying Time Diary T1-T2  Time 3 (T3)  3.4  2164.4 180.3 2126.7  173.0  95 percent Confidence Interval  t-test  df  Significance (twotailed)  Effect Size  .95  M  SD  -86.4  123.9  -140.0  -32.8  -3.3  22  0.003  -1.9  77.6  -41.9  37.9  -0.1  16  0.9  1.5  10.4  -3.0  6.0  0.7  22  0.690  -1.5  12.7  -8.0  5.1  -0.5  16  0.64  6.1  13.8  1.2  10.9  2.6  33  0.016  1.0  11.8  -3.8  5.9  0.4  24  0.7  1.5  3.2  0.4  2.5  2.7  34  0.011  0.5  1.1  0.008  0.9  2.1  25  0.05  2.0  2.6  0.920  3.1  3.8  22  0.001  0.6  2.0  -0.430  1.6  1.2  17  0.25  -121.8  166.4  -180.8  -62.8  -4.2  32  0.000  -16.0  113.9  -62.0  30.1  -0.7  25  0.5  -10.2  205.4  -81.9  61.5  -0.3  33  0.8  121.9  143.7  63.9  180.0  4.3  25  0.000  5.2  5.9  3.1  7.3  5.1  33  0.000  1.2  3.1  -9.6  2.4  1.9  25  0.1  -50.2  267.7  143.5  -43.2  -1.1  33  0.3  140.6  324.3  6.7  274.4  2.2  24  0.04  0.56  0.64  0.97  1.10  1.20  


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