Commentary: 'Ready or not here I come': developmental immaturity as a driver of impairment and referral in young-for-school-grade ADHD children. A reformulation inspired by Whitely et al. (2019).

The search for objective biological tests, sufficiently reliable, and predictive enough to be diagnostic of psychiatric disorders, continues apace - yet their discovery remains a distant dream. It seems increasingly unlikely that current diagnostic structures and concepts map biologically in a straight forward way - with heterogeneity within, and sharing across, existing diagnostic boundaries being the biological rule rather than the exception. Indeed, it now appears that the science of biological psychiatry is more likely to redraw those boundaries than it is to confirm and mark them (Sonuga-Barke, Journal of Child Psychology and Psychiatry, 2016, 57, 1). Clinical identification of childhood psychiatric disorders therefore remains, for the foreseeable future at least, an exercise in regulated social perception - reliant on the fallible and subjective judgements of parents, teachers and clinicians. Social perception of this sort is an active and motivated process and therefore prone, like all social perception, to bias and distortions - both systematic and idiosyncratic. Progress has certainly been made over the last 50 years in reducing such judgement bias by, for instance filtering perceptions through the lens of standardised instruments (questionnaires and interviews) with carefully operationalised items and a degree of reliability and validity. However, such instruments often play only a peripheral role in actual diagnostic encounters and when they are used, there is still sufficient ambiguity to leave open plenty of room for interpretation. When we acknowledge that psychiatric diagnoses are social constructions - we are not saying that symptoms of inattention, impulsivity and hyperactivity are not real or do not cluster together in meaningful ways or that they do not cause real distress and disability but that their interpretation and meaning are often informed by social constructs such as ethnic or gender norms and stereotypes (Meyer, Stevenson, & Sonuga-Barke, Journal of Attention Disorders, 2019).