The influence of minority stress-related experiences on mental wellbeing for trans/gender-diverse and cisgender youth: a comparative longitudinal analysis.

Trans and gender-diverse (TGD) adolescents are likely to experience poorer mental health and wellbeing than their cisgender peers. Minority stress theory has developed as a possible explanation for some of this disadvantage: factors such as increased bullying and discrimination lead to excess stress and reduced wellbeing. However, the evidence base remains limited. This study drew on secondary data analysis of the #BeeWell longitudinal cohort over 2 years ( = 26 042, aged 12-13 at time one, T1). We report two unregistered hypotheses relating to T1 (autumn 2021) data which was available at the time of stage-one submission: H1, mean differences in T1 wellbeing; H2, mean differences in T1 minority-related stressors. These are followed by two registered hypotheses relating to T2 (autumn 2022) data: H3, replication of T1 mean differences in T2 wellbeing; H4, predictions were made about the strength of the association between T1 minority-related stressors, controlling for sexuality and T2 wellbeing across T1 gender identity groups. At both time points cis-females, TGD and those who preferred not to say their gender had lower wellbeing than cis-males (CM), with the largest effect evident for the TGD group. TGD adolescents also showed the largest disadvantage (mean difference) compared with CM for minority stressors. Counter to H4 and minority stress theory, gender was not found to moderate the effect of minority stressors on later wellbeing. Our findings highlight the vulnerability of the TGD group in terms of wellbeing and minority stressors and are discussed with relevance for policy and future research.