Table 1 Search Terms for PubMed

Domain of connectedness

(“hikikomori” OR “socially withdrawn youth” OR “youth social withdrawal” OR “severe social withdrawal” OR “acute social withdrawal” OR “protracted social withdrawal” OR “prolonged social withdrawal” OR “primary social withdrawal” OR “hidden youth”) AND (connectedness OR relationships OR community OR peers OR friends OR friendship)

Domain of hope and optimism

(“hikikomori” OR “socially withdrawn youth” OR “youth social withdrawal” OR “severe social withdrawal” OR “acute social withdrawal” OR “protracted social withdrawal” OR “prolonged social withdrawal” OR “primary social withdrawal” OR “hidden youth”) AND (hope OR optimism OR “belief in recovery” OR “motivation to change” OR “positive thinking” OR “valuing success” OR dreams OR aspirations)

Domain of identity

(“hikikomori” OR “socially withdrawn youth” OR “youth social withdrawal” OR “severe social withdrawal” OR “acute social withdrawal” OR “protracted social withdrawal” OR “prolonged social withdrawal” OR “primary social withdrawal” OR “hidden youth”) AND (identity OR gender OR “sexual orientation” OR culture OR “dimensions of identity” OR “rebuilding positive identity” OR “redefining positive identity” OR stigma)

Domain of meaning in life

(“hikikomori” OR “socially withdrawn youth” OR “youth social withdrawal” OR “severe social withdrawal” OR “acute social withdrawal” OR “protracted social withdrawal” OR “prolonged social withdrawal” OR “primary social withdrawal” OR “hidden youth”) AND (“meaning in life” OR “meaning of mental illness” OR “mental illness experience” OR “meaning of experience” OR “social roles” OR “social goals” OR “rebuilding life” OR spirituality OR “quality of life”)

Domain of empowerment

(“hikikomori” OR “socially withdrawn youth” OR “youth social withdrawal” OR “severe social withdrawal” OR “acute social withdrawal” OR “protracted social withdrawal” OR “prolonged social withdrawal” OR “primary social withdrawal” OR “hidden youth”) AND (empowerment OR “strength-based” OR “focusing upon strength” OR “control over life” OR “personal responsibility”)