Loneliness as a public health issue in context: capturing experiences and social determinants of loneliness in diverse young adults in London & Tokyo

Initial evidence highlights high rates of depression, anxiety and suicidality in transgender and gender diverse (TGD) youth populations. However, despite many studies investigating mental health inequalities between LGBT+ and non-LGBT+ youth in the past two decades, very few quantitative studies have investigated inequalities among TGD participants as compared to their cisgender peers. The few extant studies evidencing such inequalities have only been carried out in the USA and New Zealand, among majority-White, English-speaking samples. Moreover, a major barrier to high-quality research in this area is that no consensus exists on appropriate strategies for identifying TGD youth in health surveys, because there is scarce research investigating transgender young people's views on suitability of gender identity questions or questionnaires used.

It therefore remains unknown how mental health outcomes may differ in these populations across diverse cultural settings, or in contexts with greater or lesser social acceptance of TGD people. This is especially relevant given increasing hostility towards transgender people in countries such as the UK, or countries where LGBTQ+ acceptance and visibility remains low, such as Japan. In such climates of increasing scrutiny towards transgender rights and gender-affirming care, high-quality evidence from quantifying a) the scale and b) the reasons for mental health and social inequalities among TGD youth is essential for persuading policymakers of the necessity of supportive interventions.

This mixed-methods project, embedded within a larger Wellcome Award-funded project investigating impacts of gendered social environments on young people's mental health, aims to address this evidence gap. This project will consist of three sub-studies, answering the following research questions:
1) What questionnaire items are most appropriate for identifying transgender and gender questioning young people in quantitative adolescent population health surveys?
Qualitative focus groups will be carried out with TGD young people in London and Tokyo to assess appropriateness and saliency of existing gender measurement strategies, and to allow refinement or development of new questionnaire items for use in future surveys.

2) What are the disparities in mental health outcomes (depression, anxiety) between transgender and gender diverse youth compared to their cisgender peers? To what extent do discrimination/victimisation explain these inequalities? A new survey capturing gender (using the measurement strategies developed in #1) and depression, anxiety and self-harm among secondary school-age adolescents will be conducted in London and Tokyo. Quantitative analysis will be conducted on this data to compare risk of mental health outcomes among TGD young people compared to gender-majority peers; interaction terms will be included in these models to investigate a) the extent to which victimisation experiences can account for this gap and b) whether the size of these inequalities differs between youth in the two countries (given differing levels of transgender visibility and acceptance).

3) What are the momentary and cumulative effects of affirmation/discrimination experiences on mental health outcomes in transgender young people? Using experience sampling methodology (ESM) administered via smartphones, intensive longitudinal data will be collected from transgender young people on the impact of gender-affirming and discriminatory experiences in context. Quantitative analyses of this data will be conducted to determine moment-to-moment and longitudinal impacts of these experiences on mental health outcomes.