Akiskal HS. Developmental pathways to bipolarity: are juvenile-onset depressions pre-bipolar? J Am Acad Child Adolesc Psychiatry. 1995;34(6):754–63.

Article  CAS  PubMed  Google Scholar 

Altamura AC, Dell’Osso B, Berlin HA, Buoli M, Bassetti R, Mundo E. Duration of untreated illness and suicide in bipolar disorder: a naturalistic study. Eur Arch Psychiatry Clin Neurosci. 2010;260(5):385–91.

Article  PubMed  Google Scholar 

Angst J, Adolfsson R, Benazzi F, Gamma A, Hantouche E, Meyer TD, et al. The HCL-32: towards a self-assessment tool for hypomanic symptoms in outpatients. J Affect Disord. 2005;88(2):217–33. https://doi.org/10.1186/s12888-016-0831-8.

Article  PubMed  Google Scholar 

Angst J, Meyer TD, Adolfsson R, Skeppar P, Carta M, Benazzi F, et al. Hypomania: a transcultural perspective. World Psychiatry. 2010;9(1):41–9.

Article  PubMed  PubMed Central  Google Scholar 

Baldessarini RJ, Tondo L, Vázquez GH, Undurraga J, Bolzani L, Yildiz A, et al. Age at onset versus family history and clinical outcomes in 1,665 international bipolar-I disorder patients. World Psychiatry. 2012;11(1):40–6.

Article  PubMed  PubMed Central  Google Scholar 

Bechdolf A, Ratheesh A, Wood SJ, Tecic T, Conus P, Nelson B, et al. Rationale and first results of developing at-risk (prodromal) criteria for bipolar disorder. Curr Pharm Des. 2012a;18(4):358–75.

Article  CAS  PubMed  Google Scholar 

Beck AT, Epstein N, Brown G, Steer RA. An inventory for measuring clinical anxiety: psychometric properties. J Consult Clin Psychol. 1988;56(6):893–7.

Article  CAS  PubMed  Google Scholar 

Berk M, Brnabic A, Dodd S, Kelin K, Tohen M, Malhi GS, et al. Does stage of illness impact treatment response in bipolar disorder? Empirical treatment data and their implication for the staging model and early intervention. Bipolar Disord. 2011;13(1):87–98.

Article  PubMed  Google Scholar 

Biederman J, Faraone SV, Wozniak J, Mick E, Kwon A, Cayton GA, et al. Clinical correlates of bipolar disorder in a large, referred sample of children and adolescents. J Psychiatr Res. 2005;39(6):611–22.

Article  PubMed  Google Scholar 

Brand S, Luethi M, von Planta A, Hatzinger M, Holsboer-Trachsler E. Romantic love, hypomania, and sleep pattern in adolescents. J Adolesc Health. 2007;41(1):69–76.

Article  PubMed  Google Scholar 

Brand S, Angst J, Holsboer-Trachsler E. Is the increase of hypomanic stages during adolescence related to gender and developmental tasks? World J Biol Psychiatry. 2010;11(3):594–602.

Article  PubMed  Google Scholar 

Brand S, Gerber M, Pühse U, Holsboer-Trachsler E. “Bright side” and “dark side” hypomania are associated with differences in psychological functioning, sleep and physical activity in a non-clinical sample of young adults. J Affect Disord. 2011;131(1–3):68–78.

Article  PubMed  Google Scholar 

Carta MG, Angst J. Screening for bipolar disorders: a public health issue. J Affect Disord. 2016;205:139–43. https://doi.org/10.1016/j.jad.2016.03.072.

Article  CAS  PubMed  Google Scholar 

Cate Carter TD, Mundo E, Parikh SV, Kennedy JL. Early age at onset as a risk factor for poor outcome of bipolar disorder. J Psychiatr Res. 2003;37(4):297–303.

Article  Google Scholar 

Cattell RB. The scree test for the number of factors. Multivariate Behav Res. 1966;1(2):245–76.

Article  CAS  PubMed  Google Scholar 

Chen X, Cai H, Bai W, Sha S, Cheung T, Ungvari GS, et al. Validation of the 33-item Hypomania Checklist-External Assessment in Screening Adolescents for Bipolar Disorder. Front Psychiatry. 2022;13: 897357.

Article  PubMed  PubMed Central  Google Scholar 

Correll CU, Penzner JB, Lencz T, Auther A, Smith CW, Malhotra AK, et al. Early identification and high-risk strategies for bipolar disorder. Bipolar Disord. 2007a;9(4):324–38.

Article  PubMed  Google Scholar 

Correll CU, Penzner JB, Frederickson AM, Richter JJ, Auther AM, Smith CW, et al. Differentiation in the preonset phases of schizophrenia and mood disorders: evidence in support of a bipolar mania prodrome. Schizophr Bull. 2007b;33(3):703–14.

Article  PubMed  PubMed Central  Google Scholar 

Costello EJ, Egger H, Angold A. 10-Year research update review: the epidemiology of child and adolescent psychiatric disorders: I. Methods and public health burden. J Am Acad Child Adolesc Psychiatry. 2005;44(10):972–86.

Article  PubMed  Google Scholar 

Craighead WE, Curry JF, Ilardi SS. Relationship of children’s depression inventory factors to major depression among adolescents. Psychol Assess. 1995;7:171.

Article  Google Scholar 

Crump C, Sundquist K, Winkleby MA, Sundquist J. Comorbidities and mortality in bipolar disorder: a Swedish national cohort study. JAMA Psychiat. 2013;70(9):931–9.

Article  Google Scholar 

Faedda GL, Serra G, Marangoni C, Salvatore P, Sani G, Vázquez GH, et al. Clinical risk factors for bipolar disorders: a systematic review of prospective studies. J Affect Disord. 2014;168:314–21. https://doi.org/10.1016/j.jad.2014.07.013.

Article  PubMed  Google Scholar 

Faedda GL, Baldessarini RJ, Marangoni C, Bechdolf A, Berk M, Birmaher B, et al. An International Society of Bipolar Disorders task force report: Precursors and prodromes of bipolar disorder. Bipolar Disord. 2019;21:720–40.

Article  PubMed  Google Scholar 

Feng Y, Xiang YT, Huang W, Wang G, Feng L, Tian TF, et al. The 33-item Hypomania Checklist (HCL-33): a new self-completed screening instrument for bipolar disorder. J Affect Disord. 2016;190:214–20. https://doi.org/10.1016/j.jad.2015.09.057.

Article  PubMed  Google Scholar 

Ferrari AJ, Stockings E, Khoo JP, Erskine HE, Degenhardt L, Vos T, et al. The prevalence and burden of bipolar disorder: findings from the Global Burden of Disease Study 2013. Bipolar Disord. 2016;18(5):440–50.

Article  PubMed  Google Scholar 

Forty L, Smith D, Jones L, Jones I, Caesar S, Fraser C, et al. Identifying hypomanic features in major depressive disorder using the hypomania checklist (HCL-32). J Affect Disord. 2009;114(1–3):68–73. https://doi.org/10.1016/j.jad.2008.07.017.

Article  PubMed  Google Scholar 

Fritz K, Russell AMT, Allwang C, Kuiper S, Lampe L, Malhi GS. Is a delay in the diagnosis of bipolar disorder inevitable? Bipolar Disord. 2017;19(5):396–400.

Article  PubMed  Google Scholar 

Gamma A, Angst J, Azorin JM, Bowden CL, Perugi G, Vieta E, et al. Transcultural validity of the Hypomania Checklist-32 (HCL-32) in patients with major depressive episodes. Bipolar Disord. 2013;15(6):701–12.

Article  PubMed  Google Scholar 

Geller B, Luby J. Child and adolescent bipolar disorder: a review of the past 10 years. J Am Acad Child Adolesc Psychiatry. 1997;36(9):1168–76.

Article  CAS  PubMed  Google Scholar 

Geller B, Fox LW, Clark KA. Rate and predictors of prepubertal bipolarity during follow-up of 6- to 12-year-old depressed children. J Am Acad Child Adolesc Psychiatry. 1994;33(4):461–8.

Article  CAS  PubMed  Google Scholar 

Geller B, Williams M, Zimerman B, Frazier J, Beringer L, Warner KL. Prepubertal and early adolescent bipolarity differentiate from ADHD by manic symptoms, grandiose delusions, ultra-rapid or ultradian cycling. J Affect Disord. 1998;51(2):81–91.

Article  CAS  PubMed  Google Scholar 

Geller B, Zimerman B, Williams M, Bolhofner K, Craney JL, Delbello MP, et al. Diagnostic characteristics of 93 cases of a prepubertal and early adolescent bipolar disorder phenotype by gender, puberty and comorbid attention deficit hyperactivity disorder. J Child Adolesc Psychopharmacol. 2000;10(3):157–64.

Article  CAS  PubMed  Google Scholar 

Goldstein BI, Birmaher B, Carlson GA, DelBello MP, Findling RL, Fristad M, et al. The International Society for Bipolar Disorders Task Force report on pediatric bipolar disorder: knowledge to date and directions for future research. Bipolar Disord. 2017;19(7):524–43.