RESEARCH ON "CRYING IT OUT" IN INFANCY Below is a summary of a review of the literature on the use of crying it out (CIO) in infancy (Gordon, Hill, & Forisha, 2006). Click here to download pdf. (Note: Poster pdf's are formatted for 11x17 paper.)
Research Summary:
While experts contend that parents should begin using varying amounts of crying in order to get their infants to sleep as early as 3-6 months of age, very little research has been actually conducted on children under 1 year. The majority of research on crying it out (CIO) has been conducted on toddlers and preschoolers.
Though infants under 1 year were often included, the research samples included children from wide age ranges (e.g. 6-48 months) and did not indicate the results of the study by age. So, it is unclear how the infants in the sample fared.
Only 1 study looked at infants (6-12 mos) exclusively and this study found no difference between the CIO group and control at a 4-month follow-up. The researchers suggest that this indicates that some sleep problems resolved without intervention as the infant developed.
Only 2 studies have included any infants under 6 months.
There has been no research on the use of CIO with infants younger than
4 months.
The effects of prolonged crying before sleep in infancy has never been studied.
Gordon, M. D., Hill, S. L., & Forisha, B. (2006, July). Is "crying it out" appropriate for infants? A critical review of the literature on the use of extinction in infancy. Poster presented at
the World Infant Mental Health Conference, Paris, France.
Abstract:
"Sleeping through the night" is widely accepted both as a developmental
milestone for infants, as well as a desirable event for parents;
however, there is little agreement on what constitutes normal sleep
development. While some research indicates that many infants continue
to wake at night throughout the first year, a considerable body of work
now suggests that sleeping through the night is a critical skill to be
acquired in the first 6 months. It is further suggested that parents
are significant contributors to their infants sleep difficulties.
While a variety of sleep management techniques have been tested
empirically, the most popular and well- documented approach involves the
extinction of the infants crying behavior through the withholding of
the reinforcer, parental response (crying it out). Variations of the
technique include letting the child cry for longer and longer intervals
before responding (graduated extinction, systematic ignoring, controlled crying), to
simply letting an infant cry until he/she falls asleep (cold turkey,
pure extinction). While no standard exists for the appropriate time to
begin the intervention, popular parenting advice suggests beginning
around 6 months; however, more recently parent-targeted sleep advice
advocates letting an infant cry at bedtime and during the night
beginning at as early as 3 - 4 months. Parents are told that extended
crying is not harmful to their baby and that no negative side-effects
of crying it out have been found.
A review of the key literature
supporting the use of extinction in infancy, however, reveals that the
majority of studies were not conducted on infants, but rather on
toddlers and preschoolers. Only a small subset of empirical
investigations included any infants under 1 year in the sampleand, of
those, only 2 included infants under 6 months. No studies have focused
on infants exclusively. Infants were generally included as part of a
larger sample drawn from wide age ranges (e.g. 6 - 48 months). None of
the studies indicated how many infants under 1 year were included in
the sample. In addition, outcome data was not analyzed for potential
effect variations by age. As a result, the effects of crying it out for
infants under 1 year have yet to be adequately investigated. Further,
the notion that extended crying is not harmful for infants has never
been empirically investigated.
While the stress that a crying or
wakeful infant places upon a family cannot be minimized, this paper
nevertheless recommends that research on crying it out in the first
yearas well as the advice that proceeds from itbe reexamined in light
of new understandings of early brain development and the role of
distress modulation in an infants developing self-regulatory
capacities.