What does the evidence tell us about “cry it out” ?

What is the Ferber method? Also known as “graduated extinction,” the Ferber method is an infant sleep training program developed by Richard Ferber, pediatrician and founder of the Boston Children’s Sleep Center. In a series of training sessions, caregivers leave their children alone for strictly-timed intervals, ignoring any protests and cries they might hear. When the method works, children gradually accept that no one will come to their aid, and, as a result, their behavior becomes less disruptive (Reid at al 1999).

infant in crib looking sad or pensive

If you’re considering sleep training for your child, this article will help you decide if graduated extinction is right for you. Here I discuss the following:

  • What can the experts agree about?
  • How does the Ferber method work?
  • What are the arguments for and against graduated extinction?
  • Is the Ferber method effective? Is it harmful?
  • Why hasn’t the research yet settled the controversy?
  • What are the “gentler” alternatives, and how do they measure up?

As I explain below, other methods of sleep training — methods that do not involve leaving babies alone to cry — have been tested and judged effective. Desperate, tired parents have more than one option. 

What can the experts agree about?

Although Ferber sleep training is controversial, researchers agree on many points.

Point 1: The Ferber method is not appropriate for young babies

Young babies need to feed at night, and their sleep-wake patterns are still immature. For these and other reasons, even researchers who advocate Ferber sleep training warn that sleep training is inappropriate for babies under 6 months old (France and Blampied 1999; Owens et al 1999; Douglas and Hill 2013).

Instead, parents can try out a number of safe, age-appropriate tactics for improving their babies’ sleep. For more information, see my articles about infant sleep problems and infant sleep aids.

Point 2: The Ferber method is not appropriate for children who have a conditioned fear of being left alone, or who have a conditioned vomiting response

Common sense suggests that traumatized kids should not be subjected to graduated extinction, and advocates of Ferber sleep training agree. If past experiences have taught your child to fear being left alone — and/or to respond to separation by vomiting — you should consult with a behavioral psychologist about the most appropriate approach to sleep training (France and Blampied 1999).

Point 3: The Ferber method is not appropriate as a treatment for most child sleep problems

When parents consider sleep training, it’s usually because their children are experiencing bedtime problems and/or disruptive night wakings. The Ferber method seems like a possible solution. But is it?

Graduated extinction is designed for one, narrow purpose: to get children to fall asleep without parental soothing. Judged on this basis, the method is effective (see “Arguments in favor of the Ferber method,” below). But the Ferber method is NOT designed to treat many of the sleep problems that cause bedtime battles and night wakings. For instance, the Ferber method doesn’t address

Is one of these conditions making nighttime difficult? If so, you’ll want to tackle this first, before your attempt graduated extinction. Otherwise, you risk ignoring a potentially important medical issue…or worsening a behavioral problem. So talk with your pediatrician about your concerns, and review the appropriate therapies.

For help identifying (and treating) your child’s sleep troubles, see my articles on bedtime problems, night wakings, and nighttime fears.

Point 4: The Ferber method does not teach children how to fall asleep

As Richard Ferber himself acknowledges, graduated extinction doesn’t teach children how to fall asleep on their own (Ferber 2006). Children are simply denied access to their parents, and left to work it out for themselves.

If you really want to help your child fall asleep, try this alternative to the Ferber method — a sleep training program known as “positive routines with faded bedtime.” Unlike Ferber sleep training, the “positive routines” program will teach your child how to relax and prepare for bed (Adams and Rickert 1989). You can also help your child fall sleep by following these practices:

  • Dim the lights in the evening
  • Avoid exercise and stimulating activities before bedtime
  • Avoid stimulants (like caffeine) and hard-to-digest foods before bedtime
  • Help your child cope with nighttime fears

And be mindful about the way you respond to your baby in the middle of the night. As I note in my articles about newborns and older infants, babies often sigh, jerk, or vocalize during sleep, and parents sometimes misinterpret this behavior. They assume their babies are signalling for attention, so they swoop in — and end up waking a sleeping infant! If you hang back for a bit, you may find that your baby will resume sleeping more quietly…without requiring any caregiving.

Point 5: Studies leave important questions unanswered

Researchers agree that babies under the age of 6 months should not undergo graduated extinction training. But what about older babies? Are there any risks or long-term side-effects?

Studies of human infants confirm that crying is physiologically stressful — increasing a baby’s blood pressure, heart rate, and cortisol levels (Levesque et al 2000; Luddington-Hoe et al 2002), and research suggests that infant cortisol levels are higher when they are left alone to cry (Blunden et al 2022). It’s also clear that many parents are distressed by the process of graduated extinction (Blunden and Dawson 2020). Could training lead to adverse changes in a child’s development — or in the parent-child relationship?

Advocates of graduated extinction training note that no studies yet have demonstrated that the Ferber method causes lasting harm. But the truth is we lack the kind of research that might truly settle the issue. To see what I mean, consider the following.

Testing graduated extinction: How to design a study that addresses key concerns

A well-designed experimental study isolates those variables that concern us, and contrasts them with a control condition that doesn’t include those variables.

In this case, one of the key areas for concern is leaving a crying infant in a setting where the baby can’t see, hear, or otherwise detect the presence of a caregiver.

As noted below, this feature of the Ferber method stands in stark contrast with the cross-cultural and evolutionary norm for infant care, which is for babies to fall asleep in the comforting presence of caregivers. Does this divergence from the species norm change the way children develop?

To find out, we need an experiment that contrasts infant isolation with its natural counterpart: babies going to bed with the awareness that their caregivers are present (i.e., in the same room) and responsive (i.e., ready to attend, rather than ignore, infants that become distressed).

We also need to take care that other factors are held constant. This includes baseline characteristics, like stressors in the home, but it also includes changes introduced during the experiment.

For instance, if parents in one group receive special instruction in how to time feedings for optimal sleep, the same training should be given to parents in the other condition. Otherwise, we won’t be able to tease apart causation. We won’t know which aspects of the experimental manipulation (learning about timed feedings, or practicing the Ferber Method) affected the outcome.

Finally, we need to address crucial aspects of quality control:

  • Did all parents in the treatment condition follow the same procedures?
  • If some families dropped out of the study, do we know how this might have biased the results?
  • Have the researchers devised objective measures for determining long-term outcomes (like the development of emotional regulation, personality, and attachment security)?
  • How large is the study, and what kind of families participated?

And before we reach any broad conclusions, we need to consider the specific characteristics of the study population. Can we generalize the results to other groups — including people living in different cultures?

It’s a lot to think about, but it’s necessary if we want to address questions relevant to the debate. Unfortunately, as I note below, no study yet has met the first criterion (contrasting graduated extinction with species-normal nighttime care), let alone all of them. So despite decades of research, we still know surprisingly little about how the key features of graduated extinction might influence a child’s behavior, development, and family relationships.

How does the Ferber method work?

The Ferber method is actually a variant of a sleep training program called “extinction.”

Extinction sleep training is based on the assumption that children have sleep problems because they have learned to depend on parental soothing to put them to sleep. Whenever kids are denied this parental soothing, they may stall, plead, cry, or throw tantrums to delay bedtime. Because they can’t fall asleep by themselves, kids will also be disruptive if they awaken during the night.

Parents who “give in” to their children’s demands for attention are reinforcing the problem behaviors. So the solution is for parents to put their children to bed (while they are still awake) and then leave them alone. If children cry, parents are instructed to ignore it. Parents aren’t supposed to check on their babies again unless it seems absolutely necessary (Owens et al 1999).

The Ferber method departs from extinction training in one key respect: It permits parents to check on their children, but only briefly, and according to a strict schedule.

To illustrate, the first night of Ferber training looks like this:

  1. Parents put their child to bed and then stay away for 3 minutes.
  2. After a brief check (during which the parents refrain from picking up or holding the child) the parents leave again—this time for 5 minutes.
  3. Subsequently, parents wait 10 minutes between checks until the child finally falls asleep.

For each night that follows, parents gradually increase the time between check-ins. For instance, on the second night, parents might wait 5 minutes before the first check-in, 10 minutes before the second check-in, and 12 minutes before all subsequent visits. On subsequent nights, these intervals might stretch to 20 minutes or more.

How quickly does the Ferber method work?

Some parents who try Ferber sleep training see improvements within a few days. In studies testing graduated extinction, parents may complete training within 4 weeks (e.g., Reid et al 1999).

But there are complications. During training, babies often experience “extinction bursts” — bouts of crying and distress that are more intense than anything parents have encountered before. And to some parents, this just isn’t worth it. It’s too disturbing. So they abandon the method before seeing any improvement’s in their children’s behavior.

In addition, training may fail if parents are inconsistent, and sometimes “give in” to their children’s pleas. For this reason, Ferber advises parents to stick to the routine, even if a child becomes so upset that he or she vomits. In this event, parents should clean up the mess quickly, and then leave the room and continue training (Ferber 2006). If you aren’t ready for this kind of consistency — if this runs counter to your values or instincts — the Ferber method isn’t a good fit.

Arguments in favor of the Ferber method

Is the Ferber method effective?

According to scientific studies, extinction sleep training–including Ferber sleep training–is associated with the following positive outcomes (Mindell et al 2006):

  • Children who complete training are less likely to throw bedtime tantrums
  • Children who complete training are more likely to settle down at night within ten minutes
  • Children who complete training are less likely to awaken their parents during the night
  • Parents who complete training report improvements in their own stress levels, mood, and interactions with their children

In addition to these positive results, parents have reported improvements in their childrens’ daytime behavior, perhaps because sleep training “graduates” were getting more sleep at night (Mindell et al 2006).

For parents enduring nights of sleeplessness and emotional turmoil, these outcomes are extremely important. Advocates of graduated extinction point out that parents who are sleep-deprived are at higher risk for depression and marital conflict (Mindell et al 2006). Such parents may develop negative feeling toward their children and the parent-child relationship suffers as a result. If parents can stop or reduce their children’s disruptive nighttime behavior, the whole family will benefit.

But the Ferber method isn’t the only sleep training program that delivers these benefits.

As noted below, alternatives to the Ferber method — training programs that don’t involve leaving children alone to “cry it out”– have similar track records (e.g., Skulladotir et al 2003; Matthey and Črnčec. 2012; Blunden et al 2022). For this reason, it’s important to consider the potential costs of graduated extinction.

Arguments against the Ferber method

Is the Ferber method harmful?

Although studies show that extinction sleep training can be very effective in eliminating bedtime protests and stalling tactics, many people worry about potential side effects.

Leaving children alone to cry seems to violate our deepest instincts, and no wonder.

For most of human history, our ancestors ‘ biggest sleep problem was almost certainly the avoidance of predators. Like modern-day hunter-gatherers, our ancestors slept communally and shared “watch” duties (Worthman and Melby 2002). Children snuggled  up to their parents and siblings. If children cried out, it was important to soothe them quickly.

Moreover, it was important for babies to forge close, personal ties to their caregivers. They required care and feeding for many years before they could survive on their own. In a world where 40% of children died before their 15th birthdays (Kaplan et al 2000), success depended on having somebody looking out for you — somebody who understood your needs and was committed to meeting them. No wavering. No neglect.

So ignoring an infant’s distress was a sign that something was wrong. And leaving a child alone would have constituted abandonment, if not attempted infanticide (Hrdy 2009). It therefore shouldn’t surprise us if our ancestors evolved emotional and behavioral responses to keep parents and children close.

Our evolutionary past has left its stamp in our brains. When young children are left alone at night, they may experience one of the most primal and powerful stressors known to young animals–separation anxiety (Panksepp 2000). Separation anxiety is a panic response arising from a primitive part of brain that also processes information about physical pain (Panksepp 2000).

What happens when we ignore this response? And what happens when parents act as if they are insensitive to their children’s distress? How does the Ferber method affect the stress response system? The development of attachment relationships, emotional skills, and personality traits?

In this context, it’s important to keep in mind that we can’t assume that everything is all right because a baby doesn’t cry.

In an experiment on babies in a hospital nursery, researchers recorded brain EEGs while infants experienced different forms of stimulation, including a painful heel stick. The researchers discovered there was no association between infant crying and evidence of pain signalling in the brain. Some babies cried when they were in pain, others did not. Some babies cried more intensely when they were in pain, others did not (Maitre et al 2017).

The absence of crying wasn’t a reliable indicator of a baby’s distress. Might the same be true among babies undergoing “cry it out” sleep training? When babies stop crying, it could indicate that they’re no longer distressed. Or it might merely indicate that they have given up trying to signal a caregiver who doesn’t respond. Consistent with the latter possibility, a study of babies undergoing extinction training reports that infants had stopped crying in response to parental separation. However, the babies’ cortisol levels remained elevated (Middlemiss et al 2012).

So the Ferber method has provoked concern from a broad array of parents, pediatricians, researchers, and therapists (e.g., Sears and Sears 1996; Commons and Miller 1998; Sunderland 2006). And, as noted above, we need more research to address these concerns. But why is that?

Why the research hasn’t yet sorted this out

If you’ve followed stories in the popular media, you might have gotten the impression that the controversy is over. Haven’t studies demonstrated that graduated extinction is a safe, cost-free way to solve a child’s sleep problems? The answer is no, and the reason is straightforward: Currently we lack studies that meet our design criteria.

For example, one study — highly touted in the media — tracked outcomes for more than 250 Australian infants over a period of 5 years (Hiscock et al 2007; Price at al 2012).

That sounds very promising, but there is a problem. This study didn’t actually test the effects of the Ferber method. Parents participating in the intervention received multiple forms of guidance, including:

  • background information about baby sleep patterns;
  • instructions for improving sleep by tweaking the timing of meals;
  • a recommendation to put babies to bed while they were drowsy, but still awake; and
  • personal coaching from an advice nurse.

Then parents were encouraged to choose one of two sleep training programs — graduated extinction, and an alternative approach that didn’t involve leaving babies alone.

Thus, the treatment condition amounted to a mixed bag. Parents got education, support, and coaching in a number of tactics, not just the Ferber method.

What about the control group? Parents assigned to the control condition weren’t encouraged by an assigned nurse to select a sleep training program. But parents in the control condition were at liberty to solicit advice from their regular medical providers, and they were free to adopt any nighttime strategies they wished.

Did some parents in the control condition attempt graduated extinction? We don’t know because the researchers didn’t collect information about this. But we know the parents were potentially motivated, and had the opportunity.

All the parents who participated in this study were selected because they had complaints about their infants’ sleep habits. And control-group parents didn’t just seek advice from their regular medical providers. Almost two-thirds of them said they had received help and advice from outside sources.

It wouldn’t be surprising, then, if some babies in the control group received Ferber-style sleep training.

So this study doesn’t permit us to evaluate the long-term effects of graduated extinction.

The treatment condition includes several different strategies lumped together, including many tactics that don’t involve leaving babies alone. Moreover, babies in the control group probably experienced some of the same training conditions that babies in the treatment group experienced.  What this study really tested was the effects of offering parents a package of education and support.

What about more recent experimental research?

Another group of investigators in Australia have applied a tighter focus to sleep training research (Grandisar et al 2016). They assigned some families to use graduated extinction, and contrasted the results with those of families assigned either to (1) a control condition, or (2) to a group practicing an alternative sleep strategy.

But once again, a lack of information prevents us from making key inferences.

For parents in the control group, researchers didn’t collect data on what techniques parents used to get their babies to sleep. Nor did they ask if babies slept in the same room with their parents, or somewhere else (Grandisar personal communication).

Likewise, for parents assigned to use the alternative sleep strategy, researchers didn’t collect data on sleep location for babies.

As a result, one of the variables of greatest concern to critics — whether or not babies were left to cry alone — was left uncontrolled and untested.

In addition, this study suffers from limitations related to small sample size and missing data. No more than 15 families were assigned to each condition, and many families failed to participate at certain points in the study.

For example, at the 3-month data collection time point, only about half the families checked in. The researchers filled in missing data with their own estimates (Grandisar, personal communication).

Missing data can have a big impact, particularly when we’re dealing with a small sample size to begin with. You can appreciate this if you consider a test the researchers conducted at the end of the study, 12 months after the start.

Only 7 out of 13 (54%) of families in the graduated extinction group had babies that were scored as securely attached to their parents. By contrast, babies in the control group fared a bit better: 5 out of 8 babies (63%) were scored as securely attached.

That might look bad for graduated extinction, but notice that fewer families in the control group actually participated in the test. If nobody had opted out of the attachment test, would the results have looked different?

So this research doesn’t target key questions about graduated extinction, and it’s limited by small sample size and missing data. As I write this in the fall of 2023, we are still waiting for randomized, controlled studies that can provide us with strong inferences about the long-term effects of leaving babies alone and deliberately ignoring their cries. 

Can we learn anything from non-experimental studies?

I think so. In a recent survey, researchers asked more than 2,000 parents about their experiences with sleep training. Some folks said they had used “cry it out” methods, like graduated extinction. Others said they had practiced more “gentle” techniques, like camping out. Were these choices linked with any long-term problems?

Not really. When it came to parents’ self-reported quality of life — and whether or not parents preceived their babies as securely attached — the groups were pretty much indistinguishable (Kahn et al 2023).

Similarly, a smaller, observational study tracked 178 babies from birth to 18 months, and noted how often parents left the infants to “cry it out.” Children who had been subjected to “cry it out” methods did not show higher rates of behavior problems at 18 months. Nor did they show any objectively observable differences in the nature of their attachment relationships (Bilgin and Wolke 2020).

So when parents aren’t randomly-assigned to a particular caregiving intervention — but instead carrying out strategies of their own choosing — it isn’t clear that families are suffering any serious, systematic, adverse consequences. This doesn’t mean that specific types of sleeping training can’t cause problems for specific individuals. But it suggests that parents are weighing the pros and cons, and following through with strategies that seem to work for them.

Babies and parents alike show differences in temperament, and differences in the way they respond to “cry it out” situations. Parents who perceive graduated extinction to be especially distressing are likely to reject it, and they probably avoid stress-related complications as a result. By contrast, parents who embrace graduated extinction may tend to find it less difficult: They and their babies may be more amenable to the process, and therefore less likely to suffer adverse consequences.

So what are the best alternatives to the Ferber method, and how do they stack up?

As noted above, the Ferber method isn’t the only option for parents interested in sleep training. Two popular alternatives include

  • “Positive Routines with Faded Bedtime,” which teaches babies to form new, powerful associations between certain bedtime rituals and falling asleep; and
  • “Camping out” (also known as “Extinction with Parental Presence”), where you gradually encourage your baby to fall asleep independently, but do so without leaving your baby distressed and alone.

Elsewhere, I provide step-by-step instructions for employing these “gentle” methods. But the question here is…how effective are they when compared with the Ferber method?

In the only controlled, randomized scientific study to compare graduated extinction and “positive routines” head-to-head, there were no significant differences in treatment outcomes for children (Adams and Rickert 1989).

Similarly, experiments pitting graduated extinction against “camping out” either report no differences in infant and parent outcomes (Matthey and Črnčec 2012), or differences that favor camping out (Kahn et al 2020; Blunden et al 2022). In particular, camping out was found to be less stressful for parents, and more for helpful for babies suffering from high levels of separation anxiety (Blunden et al 2022; Kahn et al 2020). You can read more about it studies here.

The takeaway?

The Ferber method can be an effective way to reduce nocturnal crying, protests, and requests for parental soothing. But it’s not the only effective method available. When choosing any sleep training program, keep the following points in mind.

  • Make sure the procedure is age-appropriate.
  • Before you begin sleep training, screen your child for underlying conditions, and treat these conditions.
  • Consider your child’s individual temperament and personality, and what kinds of interventions you are comfortable with. For example, if your baby shows signs of separation anxiety, you will likely have more success with programs that don’t involve leaving your baby alone.
  • If your child has a conditioned fear of being alone or shows signs of conditioned vomiting, consult a behavioral therapist.
  • Once you’ve decided on a plan, make sure that all participating adults understand the procedure. Consistently is important for success.

More information about baby sleep

For help with infant sleep problems, see these evidence-based pages.

References: The Ferber methods and its alternatives

Adams LA and Rickert VI. 1989. Reducing bedtime tantrums: Comparison between positive bedtime routines and graduated extinction. Pediatrics 84(5): 756-761.

Blunden S, Osborne J, and King Y. 2022. Do responsive sleep interventions impact mental health in mother/infant dyads compared to extinction interventions? A pilot study. Arch Womens Ment Health. 25(3):621-631.

Blunden S and Dawson D. 2020. Behavioural sleep interventions in infants: Plan B – Combining models of responsiveness to increase parental choice. J Paediatr Child Health. 56(5):675-679.

Commons ML and Miller PM 1998. Emotional learning in infants: A cross-cultural examination. Paper presented at the American Association for the Advancement of Science, Philadelphia, PA, February, 1998.

Douglas P and Hill PS. 2013. Behavioral sleep interventions in the first six months of life do not improve outcomes for mothers or infants: A systematic review. J. Dev. Behav. Pediatr.  34: 497–507.

Eckerberg B. 2004. Treatment of sleep problems in families with young children: effects of treatment on family well-being. Acta Paediatr ;93:126-134.

Ferber R. 2006. Solving your child’s sleep problems: New, revised, and expanded edition. New York: Fireside.

France KG. 1992. Behavior characteristics and security in sleep disturbed infants treated with extinction. J Pediat Psychol 17: 467-475.

France KG and Blampied NM. 1999. Infant sleep disturbance: Description of a problem behaviour process. Sleep Medicine Reviews 3(4): 265-280.

Grandisar M, Jackson K, Spurrier NJ, Gibson J, Whitham J, Sved Williams A, Dolby R, Kennaway DJ. 2016. Behavioral Interventions for Infant Sleep Problems: A Randomized Controlled Trial. Pediatrics 137(6).

Hall WA, Hutton E, Brant RF, Collet JP, Gregg K, Saunders R, Ipsiroglu O, Gafni A, Triolet K, Tse L, Bhagat R, and Wooldridge J. 2015. A randomized controlled trial of an intervention for infants’ behavioral sleep problems. BMC Pediatr. 15(1):181.

Hrdy SB. 2009. Mother nature: Maternal instincts and how they shape the human species. NY: Ballantine Books.

Kahn M, Barnett N, and Gradisar M. 2023. Implementation of Behavioral Interventions for Infant Sleep Problems in Real-World Settings. J Pediatr. 255:137-146.e2.

Kaplan H, Hill H, Lancaster J, Hurtado AM. 2000. A Theory of Human Life History Evolution: Diet, Intelligence, and Longevity. Evolutionary Anthropology 9(4) 156-185.

Konner M. 2005. Hunter gatherer infancy and childhood: The !Kung and others.In:BS Hewlett and ME Lamb (eds): Hunter-gatherer childhoods: Evolutionary, developmental and cultural perspectives. New Brunswick, US: Aldine.

Levesque BM, Pollack P, Griffin BE and Nielsen HC. 2000. Pulse oximetry: What’s normal in the newborn nursery? Pediatric pulmonology 30(5): 406-412.

Luddington-Hoe SM, Cong X, and Hashemi F. 2002. Infant crying: nature, physiologic consequences, and select interventions. Neonatal Network 21(2): 29-36.

Maitre NL, Stark AR, McCoy Menser CC, Chorna OD, France DJ, Key AF, Wilkens K, Moore-Clingenpeel M, Wilkes DM, Bruehl S. 2017. Cry presence and amplitude do not reflect cortical processing of painful stimuli in newborns with distinct responses to touch or cold. Arch Dis Child Fetal Neonatal Ed.102(5):F428-F433.

Matthey and Črnčec. 2012. Comparison of two strategies to improve infant sleep problems, and associated impacts on maternal experience, mood and infant emotional health: a single case replication design study. Early Hum Dev. 88(6):437-42.

Middlemiss W, Granger DA, Goldberg WA, Nathans L. 2012. Asynchrony of mother-infant hypothalamic-pituitary-adrenal axis activity following extinction of infant crying responses induced during the transition to sleep. Early Hum Dev. 88(4):227-32.

Mindell JA, Kuhn B, Lewin DS, Meltzer LJ, Sadeh A and the American Academy of Sleep Medicine. 2006. Behavioral treatment of bedtime problems and night wakings in infants and young children. Sleep 29: 1263-1281.

Owens JL, France KG, and Wiggs L. 1999. Behavioural and cognitive-behavioural interventions for sleep disorders in infants and children: A review. Sleep Medicine Reviews 3(4): 281-302.

Panksepp J. 2001. Affective Neuroscience: The Foundations of Human and Animal Emotions. New York: Oxford University Press. Reid MJ, Walter AB, and O’Leary SG. Treatment of young children’s bedtime refusal and nighttime wakings: A comparison of “standard” and graduated ignoring procedures. Journal of Abnormal Child Psychology 27: 5-16.

Price AMH, Wake M, Epi GD, Ukoumunne OC, Hiscock H, Epi GD. 2012. Five-Year Follow-up of Harms and Benefits of Behavioral Infant Sleep Intervention: Randomized Trial. Pediatrics 130(4):643-51.(doi: 10.1542/peds.2011-3467)

Sadeh A. 1994. Assessment of intervention for infant night waking: Parental reports and activity-based home monitoring. J Consult Clin Psychol 62(1):63-8.

Sears W and Sears M. 1996. The fussy baby book: Parenting your high-need child from birth to age five. New York: Little, Brown and Company.

Skuladottir A, Thome M, and Ramel A. 2005. Improving day and night sleep problems in infants by changing day time sleep rhythm: A single group before and after study. Int J Nurs Stud. 42(8): 843-850.

Sunderland M. 2006. The Science of Parenting. New York: DK Publishing.

C.M. Worthman and M. Melby. 2002. Toward a comparative developmental ecology of human sleep. In: Adolescent Sleep Patterns: Biological, Social, and Psychological Influences, M.A. Carskadon, ed. New York: Cambridge University Press, pp. 69-117.

Was this article helpful? If so, try browsing through the parenting science index or use the search button at the top of the left hand column to find something specific.

Content last modified 9/2023. Portions of the text derive from earlier versions of the same article, written by the same author.

image of infant looking pensive in crib by SurkovDimitri / istock


Please enter your comment!
Please enter your name here