Project Summary This proposal seeks continued support to expand a powerful new health equity resource, the National Couples’ Health and Time Use Study (NCHAT). NCHAT is the only population-representative study (N = 3,642 ages 20- 60) with large subsamples of sexual and gender diverse (SGD; 45%) and racially and ethnically diverse (RED; 38%) coupled adults fielded during the pandemic with comprehensive measurement including groundbreaking state and county structural racism, sexism, and cis heterosexism measures. The COVID-19 pandemic and the co-occurring period of intense racial trauma exacerbated and laid bare the health inequities experienced by RED and SGD populations in the US. Attacks on the SGD and RED populations are ongoing with alarming numbers of targeted harmful policies. Health disparities for RED and SGD populations are preventable, and identifying their social determinants and underlying mechanisms is urgent. Aim 1. Reinterview and refresh the NCHAT sample. We propose to collect four additional waves of survey data and two waves of time diary and experience sampling method data. These short and frequent surveys allow flexibility with the inclusion of new content tracking the impacts of period shocks, such as COVID-19 or the aftermath of racial trauma, and the factors that exacerbate or mitigate these impacts during an era of growing mental health crises. As nearly 30% of individuals in their twenties identify as SGD, a refresher and oversample to include 300 new respondents will be added. Aim 2. Open the NCHAT panel so a diverse body of health equity scholars drive question content. Current population data infrastructure on health disparities is outmoded because 1) only select researchers decide on survey content and 2) a focus on repeated measurement can stymie innovation. Working with our inclusive advisory board, we seek to upend this system and ignite cutting-edge research with the inclusion of items contributed by health equity scholars across disciplines and institutions. These data will be rapidly released. Aim 3. Assess SGD trajectories of mental health in an era of escalating threats to SGD families. We will test vulnerabilities (structural and interpersonal discrimination and SES); strengths (social support, SGD socialization, identity centrality); and family functioning as mechanistic predictors during a period of growing anti- LGBTQ+ bills. Aim 4. Examine RED trajectories of mental health with a focus on recovery and deterioration. We will evaluate how couple stability and relationship functioning, social and community support, and structural and interpersonal experiences of discrimination act as mediators and moderators of trajectories of mental health in the wake of the pandemic and continuing racial trauma. Without longitudinal data and flexible measurement, scientific knowledge about the mechanisms underlying RED and SGD disparities will be stymied. This multi-disciplinary team is deeply invested and committed to amel...