PROPOSAL SUMMARY Significance: Loneliness has become a public health imperative given mounting evidence of associated morbidities when it is not addressed, including increased risks for Alzheimer's disease and related dementias (ADRD). Over 40% of older adults are estimated to suffer from loneliness, further underscoring the pressing need for study. In February 2020, the National Academies recommended more research into known risk factors of loneliness to inform novel screening and intervention strategies. One particular risk factor, hearing loss (HL), affects two-thirds of all adults over the age of 70 years in the United States and is projected to increase by an estimated 70% over the next four decades. The proliferation of HL can exacerbate distal outcomes like ADRD that are associated with loneliness. Current loneliness interventions have shown limited efficacy, and the vast majority do not clearly address HL. As a potentially modifiable risk factor, studying HL's relationship with loneliness will add to the evidence base and contribute to developing effective solutions. This training proposal supports the applicant's long-term goals to promote healthy aging through improving understanding of hearing health and its role in facilitating healthy social connections. The proposal will lay the groundwork for a program of research established using the NIH Stage Model for Intervention Development as a guiding framework. Specific Aims: Through a sequential explanatory mixed methods design, we aim to: (1) Examine pure tone audiometry's association with loneliness and hearing handicap as a moderator, (2A) Describe perceptions and experiences of loneliness and hearing handicap among older adults with HL, and (2B) Integrate data from aims 1-2A to explain the contributing roles of HL and hearing handicap to loneliness. Approach: Aim 1 involves multivariable adjusted logistic regression models examining additive and multiplicative interactions from hearing handicap scores reported through a validated survey on the association between a gold standard measure of HL (audiometry) and loneliness (Three-Item UCLA Loneliness). Methods include secondary analyses of population data from a community-based, racially/ethnically and regionally diverse older sample. Aim 2A involves analyses conducted via recommended guidelines for Qualitative Description with data collected from theoretically-guided interviews with purposively sampled community-dwelling older adults. Aim 2B involves using joint displays arraying quantitative and qualitative data to explain thematic findings. Fellowship Training: As the first audiologist in the PhD program at Johns Hopkins Nursing, the proposed transdisciplinary training will prepare the applicant through rigorous coursework, professional development activities, and mentored research experiences to successfully complete the aims of this proposal and advance the findings into subsequent innovative translations as a clinician scientist an...