Possums Sleep - Science Based?

[guevaraj]

I regularly see Possums Sleep recommended as a science-based infant sleep approach, rooted in research.

Data on its effectiveness appears to be mixed.

• This study (157 mother infant pairs), for example, found that while breastfeeding rates increased in the group exposed to the Possums sleep approach, overall sleep parameters were the same between the Possums group and the control group.
• This study (20 mother infant pairs) showed an improvement in infant sleep and maternal depression according to pre/post intervention questionnaires, though it did not include a control group so its IMO quite hard to unpack if this is related specifically to the intervention or just time.
• This study (64 parents) showed that on the whole, people liked the intervention though also did not include a control group.
• This study (author manuscript, 144 HCPs) suggests using the Possums training method with health care providers... teaches them about sleep, and about the method, effectively.

On the whole, these outcome results don't suggest to me that Possums sits heads and shoulders above other sleep training methods in terms of results. For example, graduated extinction (Ferber) has a broader body of evidence behind it that more commonly includes control groups, which would generally give me more confidence in that approach.

However, I regularly see Possums recommended online as one of the most science-based approaches to infant sleep and described as the only 100% science-based approach to sleep. I'd love to understand why. Is there more substantial science used in the method itself? Is this science-washing? What's going on here?

(FYI - the Possums website is down due to what sounds like financial trouble, so if there is more information to be gleaned elsewhere on the internet, please advise.)

 

[simondarok]

@guevaraj I don’t think Ferber and possums is an apples to apples comparison.

Ferber is a behaviouralism-based intervention focused on decreasing the amount of crying/signalling during the night time. My understanding is that it is fairly effective in that goal for many babies.

Possums is a more holistic approach regarding caregiver mental health, circadian rhythms and “cry-fuss” behaviour as Dr. Douglas refers to it - but more in the context of what is regarded as “ovetired” not in the context of night wakings.

I also think people who use either method have different proximal goals. I guess you could argue that overall most parents want to have a more pleasant and less stressful parenting experience but values and beliefs are going to inform what methods people deem acceptable to achieve those goals.

 

[guevaraj]

@simondarok Thanks, this is a great point. I partially compare it because it comes up so commonly in sleep training conversations but also because Douglas herself lays out her method as an alternative to sleep training and calls it a "parent baby sleep program." It also seems pretty specific in this doc where Table 1 lays out Possums vs behaviorist approaches vs normalizing night wakes (which I guess is a sort of layman's "not sleep training."

I also am not sure the rooting in caregiver mental health and circadian rhythms are that distinct between the two - e.g., Weissbluth's Healthy Sleep Habits, Happy Child (which generally advocates for an extinction based approach) is well cited and includes explanations of circadian biology, as justification for where and how behavioralist approaches may make a difference.

Definitely hear you on the different set of goals—I don't mean to say the approach itself is wrong, just that it's not clear to me that its an inherently more science-backed approach than other sleep management approaches for parents.

 

[simondarok]

@guevaraj I confess to not being familiar with a lot of sleep training lit but my understanding was that Ferber was the originator of what most modern sleep training is? So Weissbluth may be familiar with circadian rhythms and able to speak on them but I don’t know that they necessarily play a role in the Ferber approach inherently.

Whereas the focus on possums is a lot more based on having babies differentiate between night and day by having daytime be bright, stimulating, active etc.

I agree that possums is more of an “alternative to” sleep training rather than a form of it. However if someone really wanted they could probably use both approaches together with minimal issue.

The gist I get is that the effectiveness of Ferber is well supported and there is no convincing evidence of the theoretical harm for it. Unfortunately I feel like there’s a lot of corollary claims like that “babies need to be taught how to put themselves to sleep” which I have not seen a scientific backing for.

I think of possums as being sort of in it’s infancy. To me it seems pretty logical and in keeping with things I already know and my own experience with it was positive. I think it will take a bit of time before there’s more conclusive science. Just my layperson opinion though

 

[guevaraj]

@simondarok Both Weissbluth and Ferber you could say popularized the modern concept of sleep training (Ferber's first book was in 1985, Weissbluth's in 1987). The distinction between the two is generally that Ferber advocated for graduated extinction (timed checks) and Weissbluth advocated for full extinction (cry it out).

(Of course, sleep training as a concept predates them both, e.g., 1830s German medical literature suggests waiting to see if baby resettles on their own vs rushing to comfort, and "cry it out" was first documented as a term related to baby care in the 1890s.)

Both Weissbluth and Ferber I would see as generally equivalent in terms of how their ideas have influenced modern concepts of sleep training. Weissbluth specifically spends a significant section of the 5th edition of the book (and perhaps earlier ones, I just only read the 5th) talking about how day/night cycles develop in infants, HPA development, and the role of light and activity in helping infants distinguish day and night.

I think you're right that the effectiveness of the Ferber method is well documented and as you point out, the Possums method is newer. What I want to understand is if the Possums method is using better underlying science than other sleep training methods.

 

[fromtheearth]

@guevaraj In The Discontented Little Baby Book by Pamela Douglas, the reasoning behind the method is supported by citing many studies. I cannot tell if this is cherry picking or not, but maybe someone else can comment on that.

 

[guevaraj]

@fromtheearth Thank you! I read this piece (though not the book) which has an extensive citation list, but I have a few qualms (though I need to read it in more depth so these qualms may well be unfounded).

First, it's relatively self referential - while the reference list is extensive, the most common references I found were to Douglas' own prior work. That can be normal if you're doing field pioneering work but always tends to raise personal flags for me because you'd ideally like to see a set of independent researchers validating and reproducing findings.

In a few places, it felt to me that the language was a fair bit stronger than what the underlying sources stated. I checked out a few and felt the conclusions were overstated, but have not gone through the entire source material. For one example, in the section around tired cues, Douglas writes: Prescriptive lists of tired cues teach parents to read their babies through a “tired” filter—constantly looking for and finding signs that their baby needs more sleep (Reyna & Pickler, 2009; Swain et al., 2007)

Reyna & Pickler is was published in 2009 in the Journal of Obstetric Gynecologic and Neonatal Nursing (impact factor 2.042/10). It articulates why synchrony between mother/infant pairs is useful in feeding, and what tools and working models researchers have to measure and evaluate them.

Swain is an incredibly well cited article from the Journal of Child Psychology and Psychiatry (impact factor 7.035/10) looking at the brain basis of parenting. It also looks at how responsiveness to infant cues wires and rewires parental brains, and looks at some of the neurobiology of how changes are occurring.

Neither, as far as I can tell, say anything at all about how a list of tired cues teach parents to read babies through a tired filter. This is .... concerning? I would read that sentence from Douglas and assume that Reyna and/or Swain is a study done on parents that looked at (for example) how telling parents a set of infant cues changed their behavior or perhaps led to them putting their babies down too much. But instead, that sentence is all opinion—the cited studies emphasize that parents and babies should be responsive to one another and a bit of how that happens and how we measure it, but don't say anything at all about how the wrong list of cues can change parental behavior.

Again, I haven't gone through the whole citation list in detail so its entirely possible I've picked an example that isn't indicative of Douglas' broader approach. And on its face, the concept that infants do best when parents respond to them most of the time makes sense (and is, IMO, not in conflict with sleep training since generally parents sleep train because their ability to be safe, responsive caregivers is compromised). So I don't necessarily quibble with the general point of view that responding to infant needs is a valid sleep training approach—but I'm not sure I am convinced that Douglas' method is the most-science-based-of-them-all (if that's even a thing).

 

[paulinderjeetkhokher]

@guevaraj It never seemed to me that Possums was about sleep training. More like understanding infant sleep and adjusting your expectations to tolerate it.

 

[ft89]

@paulinderjeetkhokher This is my take too - I read the book during pregnancy and what I really took from it was to trust my instincts and to not get too hung up on sleep just take baby outside and crack on with your day if they simply won’t sleep. I did like referring back to it in the early newborn days when I thought I was losing my marbles due to the lack of sleep and found it wasn’t a prescriptive parenting book which was a nice change from others I’d read. I took the advice in the book with a a grain of salt and used it as one of many pieces of information I’ve based my parenting (and approach to sleep) on.

 

[paulinderjeetkhokher]

@ft89 I agree. It totally saved my sanity and still does as my LO still wakes at night but those techniques have helped me so much to just kind of live with it and still have a full life, knowing eventually he will sleep more.

 

[guevaraj]

@paulinderjeetkhokher Thanks! The reason I thought of it as sleep training (and again the website is down so it's entirely possible its framed differently in how they describe the approach) is that Douglas calls out a few times that there is a behaviorist sleep paradigm, there is an evolutionary sleep paradigm, then there is Possums (see Table 1 here).

Understanding infant sleep and adjusting your expectations to tolerate it would be the "existing alternative paradigm" in that table, which is distinct from how she characterizes Possums - Douglas is proposing specific interventions that improve maternal sleep efficiency (and so presumably infant sleep) which is why I think of it as sleep training.

Instead of creating daytime schedules or suggesting controlled crying, her interventions are greater day time activities, nighttime sensory cues and activities that increase sleep pressure alongside parental acceptance therapy.

 

[paulinderjeetkhokher]

@guevaraj Oh, I guess I could see that. I think her revolution is just moving away from all of the 1950s Ferber type stuff that still dominates most of sleep training, and returning to following the infant's natural pattern, while going about your normal business. Traditional sleep training has become so entrenched that just ignoring all those rules really does seem revolutionary, lol. Take a look at the website once it's back up. There's some good info there.

 

[the_precious_one]

@guevaraj My take on it may be a bit unconventional. I think it's not really possible for one sleep approach to be much more science-backed than others (assuming none are total quackery).

To me, infant sleep biology research - sleep rhythms, sleep cycles, the need for baby to self-settle during brief forays into light sleep for the longest sustained sleep period to lengthen, etc. - has been around for a while and is fairly easy to understand, and so most decent sleep programs and approaches incorporate this core information in one form or another. It's sleep ecology though and the "how do we get to that self-settling" that differs between approaches. And that - which path to self-settling is better or more science-backed - is difficult to study and compare. For example, if the Possums approach is shown to improve breastfeeding rates and somewhat ease parental stress, is it more or less science-backed than graduated extinction that shows faster results in terms of longer sustained sleep stretches for the baby and lower PPD for parents? Would we assign the same or different weight to these outcomes?

If I were to create a sleep program, I would explain the sleep biology and then let parents choose whichever (safe and responsive) path of getting there speaks to them. I think this would be solidly rooted in science, but I bet it wouldn't be marketable as it's not catchy or specific enough.

Sorry for the ramble - this question of what is truly science-based has been on my mind lately!

 

[guevaraj]

@the_precious_one This is really fascinating - while I agree it wouldn't sell well, that is absolutely the sleep program I'd probably want to do!