By Courtney Schley
Emily Oster, a professor of economics at Brown University, offers parents help in finding signals in the noise of parenting advice with her new book, Cribsheet: A Data-Driven Guide to Better, More Relaxed Parenting, from Birth to Preschool. In it, Oster tackles some of the big choices parents face in the early years of child-rearing, from breastfeeding to sleep to potty training. Oster doesn’t just analyze the advice coming from stalwarts like the AAP, CDC, and WHO as well as from strangers on social media; she also looks at the actual data, studies, and research on which those recommendations are built. The goal, Oster writes, is that “armed with the evidence and a way to think about decisions, you can make choices that are right for your family.”
Oster’s methodical, analytical approach resonates with how we aim to tackle these kinds of questions at Wirecutter when researching, testing, and recommending gear for babies and kids. We spoke with Oster about weighing risk and safety, the Rock ‘n Play recall, choosing baby formulas, and more.
The interview has been condensed and edited for clarity.
With Cribsheet, you were looking at bigger decisions, like “Do I breastfeed or do I formula feed?” and “Do I sleep train?” Could parents apply the same type of data analysis you used in Cribsheet to deciding what baby and kids gear to buy?
I think it is certainly the case that those decisions, as you say, probably aren’t as important or as big. But they have the same feature of cost and benefits. Particularly with baby products, there are a lot of claims or concerns about safety. It can actually be pretty hard to figure out what the data says about whether a product is safe or not. I think that is sort of amenable to the same kinds of analyses. In addition, a lot of this book is about decision making and how you weigh the costs, either of money or space in your house, against the benefits of whatever this product is.
You wrote about the Rock ‘n Play sleeper in your book, and said your daughter was a fan. I assume you heard about the recall that happened about two weeks ago. How would you approach a scenario like that?
We often assume in these discussions that the alternative is completely safe, that there’s some baseline where there would be no risk. So, you can use the Rock ‘n Play, which has this risk. Let’s stipulate that that risk is positive but small—probably very small. The question is, what else would you be doing? What is the alternative? This is where I think some of these discussions lose the thread, because they don’t think about what the alternative is.
For a lot of families, the Rock ‘n Play is a really useful way for them to get their kids to sleep. If the thing you’re going to do instead of using the Rock ‘n Play is go to sleep on the sofa with your baby, then that is much riskier. If the alternative is to have your kid asleep on their back alone in the crib, that probably is safer. We sometimes miss these kinds of “what is your alternative” questions, which I think should have a bigger part of the discussion.
Formula companies are investing a lot of research into developing new proprietary ingredients, with the idea that they will make formula more similar to breast milk and improve brain development or gut health. But they can cost two or three times as much as basic formulas, which the FDA and AAP say are nutritionally sound. How can parents navigate products like formula, where they see a lot of choice and big cost differences?
I used some formula with both of my kids. I used the basic Similac formula that came in the bottle. Particularly because of the emphasis on breastfeeding, there is a feeling that you’re starting from a baseline that formula is kind of bad. So if you’re going to do this terrible thing to your baby, at least you should spend some money to do it right.
These formulas are extremely similar. It’s an incredibly heavily regulated area. The scope of possible ingredients you can have is just very limited. Then you go, “Okay, but what about these extra things?” The answer is, we don’t know. If you think of the goal of formula as “Let’s put in all this stuff so it’s just as good as breast milk,” a lot of what I talk about in the book is that many of these reported benefits, particularly around things like brain development, I don’t think are supported in the data. Even the difference between formula and breast milk doesn’t actually seem to show up in the best studies.
Presumably the differences between different kinds of formulas has to be bounded by the difference between formula generically and breast milk. So that suggests that some of these claims are not likely to be highly supported in the data.
A few of these additives, particularly probiotics, actually seem to benefit a lot of kids, including kids who are breastfed. Some kids’ digestion is improved by probiotics no matter what they’re eating. So that’s sort of a long-winded way to say that I think it is unlikely we will learn that some formula additives are super important for anything.
I understand the strength of those marketing messages, where they put “helps grow brain” on the bottle …
[Laughs.] Who doesn’t want their kid to have a good brain? I want the bad brain, the low-brain formula.
That goes to the question of expense, which is a big concern for a lot of parents, understandably. “Am I putting my kid at risk, am I making a bad choice for them, if I want to buy the $50 car seat instead of the $250 car seat?” Do you think that data overall can help parents feel more comfortable choosing cheaper stuff for their kids?
I’m not sure data helps there so much as understanding how this kind of stuff is regulated. You can’t just make a car seat. There are actually rules about what kind of safety features your car seat has to have. Everyone, including the cheapo car seats, is adhering to that. There’s a sense in recognizing that that is helpful.
The studies that organizations rely on to make safety or behavioral recommendations aggregate risks and benefits across a big population. Do you think that overall a lot of parenting recommendations, whether about behavior or products, fail to take into account that these are going out to individual people who have a whole web of different influences, and even just preferences?
There are two pieces that I agree with, and would flesh out a little more. Let’s say for some product or some behavior, there is exactly one effect. If you do this, it gives you two IQ points, or whatever. This is a point I make in the book: Even if that data is exactly the same for everybody, the preferences of parents are going to determine what people actually want to do. By making these blanket recommendations, like “everybody should sleep like this” or “everybody should breastfeed,” we are ignoring that there are differences in preferences which should be taken into account.
There’s a separate and in some ways even more complicated issue, which is that it’s very unlikely that the effect of any behavior is exactly the same for everybody. Even when we do studies, we’re often looking for the average effect. The truth may be that for some people the effect of this is really positive, and for some people it’s kind of negative. That’s something we very rarely capture in our data, and it probably also relates to people’s preferences. So it may be that for people who really want to do something, who really want to co-sleep, maybe co-sleeping is more beneficial. Both of those things contribute to some of the even deeper limitations of what we can learn from data in these settings.
Read the original article on Wirecutter here.
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