Generation Victoria (GenV) is a longitudinal, population-based study of Victorian children and their parents that will bring together data on a wide range of conditions ,exposures and outcomes. GenV blends study-collected, study-enhanced and linked data. It will be multi-purpose, supporting observational, interventional, health services and policy research within the same cohort. It is designed to address physical, mental and social issues experienced during childhood, as well as the antecedents of a wide range of diseases of ageing. It seeks to generate translatable evidence (prediction, prevention, treatments, services) to improve future wellbeing and reduce the future disease burden of children and adults.

The GenV Cohort 2020s is open to all children born over a two-year period, and their parents, residing in the state of Victoria Australia. The GenV Cohort 2020s is preceded by an Advance Cohort of children born between 5 Dec 2020 and 3 October 2021, and their parents. This comprises all families recruited at GenV's Vanguard hospital (Joan Kirner Women's and Children's) and at birthing hospitals throughout Victoria as GenV scaled up to commence recruiting for the GenV Cohort 2020s. The Advance Cohort have ongoing and full participation in GenV for their lifetime unless they withdraw but may have less complete data and biosamples.

GenV aims to create large, parallel whole-of-state birth and parent cohorts for discovery and interventional research. The four cornerstones of GenV's first decade are:

• Consented Cohort - Targeting all Victorian children born in a 2-year period and their parents, with the first major recruitment period targeting newborns and infants
• Biosamples - Curation of residual universal biosamples and collection of new biosamples
• Accessing existing data - Continuously-updated linkage to or ingestion of extensive administrative, service, geospatial and clinical datasets, including prospectively-collected datasets from before the child's birth
• Early School Wave - GenV-led phenomic assessment during the child's early school years.

Additional foundations activities are:

• GenV-collected survey data
• Integrated studies - Collaborative observational or interventional research studies embedded within or alongside GenV, with ethically-supported agreements that include arrangements for data sharing.
• IT and data platforms - to support all GenV activities including user research data access.

GenV focuses on 10 big issues: COVID, healthy pregnancy, healthy newborns, equity, climate & environment, mental health, healthy development, allergy & immunity, infection, and obesity & diabetes, with a cross cutting commitment of population genomics. These focus areas drive current planning for data collection but are not intended to be exhaustive and may change over the life of the project.

GenV partnered with all birthing hospitals across Victoria (i.e. 58 hospital sites). In-hospital face-to-face recruitment took place during the newborn period (December 2020 - November 2023). Recruitment visits were completed by trained study staff with clinical and/or research backgrounds, including initial GenV-collected data and biosamples. GenV remains open to eligible families through phone and/or self-guided recruitment.

Participant-provided data are collected digitally (e.g. via website or smart phone app) about four times per year from age 3 months to 1 year, then 6-12 monthly until 5 years, taking 3-20 minutes per session. A face-to-face visit is planned for when the index child is around 6-years of age, completed by trained study staff with clinical and/or research backgrounds. The project duration is expected to be at least 10 years and potentially lifelong for its participants, dependent on study funding and willingness to continue.

GenV estimated that the sampling frame for the main Cohort 2020s would comprise 150,000 children,150,000 birthing parents, and 130,000 (i.e. for 90 percent of children) second parents. GenV's recruitment rate is around 30% of all Victorian families with an eligible child. With a current sample size of 50,000 children, calculations show that this can detect odds ratios of around 1.3 for an outcome with 1.5% prevalence and an exposure with 20% prevalence.

Inclusion Criteria (Children):

• Birth date between 4th October 2021 and 3rd October 2023
• Live at the time of recruitment
• Residing in Victoria at the time of recruitment
• Has a legally acceptable representative capable of understanding the informed consent document and providing consent on the child's behalf, who provides a signed and dated informed consent form (e.g. a parent/guardian)

Inclusion Criteria (Adults):

• Be a parent or guardian of a child who meets the eligibility criteria above
• Provide a signed and dated informed consent form or have a legally acceptable representative capable of understanding the informed consent document and providing consent on the participant's behalf.

Exclusion criteria:

• Children who are deceased at the time of recruitment (i.e. still born or died after birth) and their parents/guardians
• Families unable to provide informed consent in any of the languages available

All children living in the state of Victoria, Australia, born between 4th October 2021 and 3rd October 2023, and their parents/guardians.

GenV is designed as an Open Science resource. Privacy-protected child and parent research data will be made available spanning:

• Individual physical and mental health, education, social and bioassay data
• Neighbourhood data (eg pollution, childcare)

Data will in general be made available after completion and data preparation for entire waves of data collection. An access policy is currently under development.

GenV's biosamples are small in volume and depletable. Therefore, bioassay requests are most likely to proceed if they:

• Are for all participants in GenV (or for the whole subgroup with that biosample)
• Would be valued by many researchers
• Generate broad, not hypothesis-specific, biodata (eg -omics panels)
• Are supported by funding and quality processes.

The first wave of data is expected to become publicly available in 2026. Subsequent releases will follow completed waves of data collection and are expected to be available indefinitely. Limited data are accessible to some collaborators prior to this, for example to support specific operations of integrated studies.

Data will be made available to approved end-users for analyses that achieve the aims in the approved proposal. Approval is based on:

• The research aims to improve health, development, or wellbeing
• The proposed use of the data is covered by ethical approval
• GenV assesses the safety and expertise of the applicant and the institution/organisation
• Samples/data are used with participant privacy protection in place
• Users agree to GenV's conditions of use.