‘Paediatric bipolar disorder’ (PBD) is a controversial diagnosis where often prepubertal children as well as adolescents, who may have a range of psychiatric disorders or symptoms, are diagnosed with a severe mental illness requiring lifelong medication. Clinically, it has often been applied in the United States but rarely in most other countries. A meta-analysis (Van Meter et al., Journal of Clinical Psychiatry, 2011, 72, 1250) claimed that the prevalence of PBD was similar to adults at 1.8% with no difference between the United States and other countries. This conclusion has been highly cited. Login using your SSSFT NHS OpenAthens details for full text.