What sleep training method is the best?

What the evidence says

There isn't one 'winner' among sleep training methods. A randomized trial published in Pediatrics compared graduated extinction (checking in at intervals) with bedtime fading (gradually moving bedtime later) against a no-training control group, and found both methods significantly cut how long babies took to fall asleep and how much they woke overnight, with no rise in stress hormone levels and no differences in attachment security or emotional/behavioral problems a year later. A broader review of psychologists' recommendations describes the two main approaches: standard extinction ('cry it out'), where parents don't respond to crying after a consistent bedtime routine and usually see results within three to five days, and graduated extinction, which is slower but lets parents check in periodically and is generally more popular for that reason.

A systematic review and meta-analysis of behavioral sleep interventions found they reduce child sleep problems and improve mothers' sleep quality, though the same review did not find a clear effect on the exact number of night wakings or on maternal depression, showing the benefits vary by outcome measured. A small pilot trial comparing a gentler 'responsive' approach with controlled crying found sleep results were similar between groups, but mothers using the responsive method reported less stress, suggesting the 'best' method may depend on which outcome (baby's sleep vs. parental stress) matters most to your family. One dissenting systematic review focused on infants younger than 6 months concluded that behavioral sleep training in that very young age group hasn't been shown to reduce crying or prevent later sleep or mood problems, and flagged a risk that pushing sleep training too early could backfire.

This lines up with general advice that most structured sleep training is designed for and studied in babies 6 months and older. No Canadian body has issued a guideline ranking sleep training methods against each other; Canadian pediatric sleep sources focus more on safe sleep practices and general sleep hygiene than on picking a single 'best' training technique.