Commentary: Does 'cry it out' really have no adverse effects on attachment? Reflections on Bilgin and Wolke (2020)

In their recent paper published in JCPP, Bilgin and Wolke (2020a) argue that leaving an infant to 'cry it out', rather than responding to the child's cries, had no adverse effects on mother-infant attachment at 18 months. This finding opposes evidence across a wide range of scientific fields. Here, we outline several concerns with the article and argue against some of the authors' strong claims, which have already gained media attention, including a report on the NHS website. We suggest that the authors' conclusions should be considered one piece of a larger scientific whole, where 'cry it out' seems, overall, to be of detriment to both attachment and development. Crucially, we are concerned that this study has issues regarding power and other analytical decisions. More generally, we fear that the authors have overstated their findings and we hope that members of the public do not alter their parenting behaviours in line with such claims without further research into this controversial topic.