Welcome to the final report on the TANDem project. In this report we will summarise key activities, achievements and celebrations from year 4 of the project and present some overall reflections on our journey with the TANDem project.

The TAND consortium set out to develop a set of international consensus recommendations for the identification and treatment of TAND. These focus on the seven natural TAND clusters (Autism-like, Dysregulated behaviour, Eat/Sleep, Mood/Anxiety, Overactive/Impulsive, Neuropsychological, and Scholastic clusters), and an eighth wraparound Psychosocial cluster.

We are delighted to announce that the new checklist, the TAND-SQ, has been developed and is now published in the journal of Pediatric Neurology. The full checklist can be accessed via the article and can be used freely by families and individuals living with TSC.

Thank you to all our presenters who made the 2023 TAND Mini-Symposium such a great success! We had approximately 80 participants attend the event and engage in fruitful discussions about a wide range of presentations on TAND topics. Read further for access to the abstracts and recording of the event.

On TSC Global Awareness Day (15 May) we celebrate the power of research in partnership with TSC families. Watch this short movie to learn more about the TANDem project.

An international group of experts in the TAND consortium met with local families, clinicians and researchers to present up-to-date information on TSC, TAND, the TANDem project, and discussed issues of local interest to participants in round-table discussions.

In this report we present key milestones over the last year and highlight some important and exciting activities and achievements by the TAND consortium during this period. It was exactly 10 years ago, in 2012, that the term ‘TAND’ (TSC-Associated Neuropsychiatric Disorders) was coined at an international consensus conference in the USA.

The TAND consortium hosted an online Mini-Symposium in April 2022. Emerging and established TAND researchers across the globe were invited to submit abstracts for short ‘rapid fire’ presentations on their research.

The annual report 2021 documents the progress that has been made in the second year of the TANDem project in the context of COVID-19, illustrating the remarkable resilience and ongoing commitment of the TAND Consortium members to the project and its greater goals.

The TANDem consortium presented an abstract at the 24th World Congress of the International Association of Child & Adolescent Psychiatrists and Allied Professions (IACAPAP) organized virtually in December 2020.

An update on the TANDem project was presented at the annual DCAP (Division of Child and Adolescent Psychiatry) research mini-symposium virtually held on 27th November 2020.

At the International TSC Research Symposium organized virtually on 13th November 2020 an update was given on the first year of the TANDem project.

On 9-11 November 2020 a virtual TAND consortium consensus meeting took place to look back on all the work done in the first year of the project, and to set the goals and focus for the next year.

The first annual report documents the very hard work that has been done in year 1 to get the TANDem project going, encouraged by the dedication and hard work of all TANDem Consortium members, and by the ongoing support and enthusiasm for the project from the global TSC community.

The TANDem project had a launch meeting in November 2019 which took place at the Katholieke Universiteit Leuven (KUL) from 17–19 November 2019. The meeting was coordinated by Stephanie Vanclooster and hosted by Liesbeth De Waele.

We were delighted to present our TANDem poster at the 22nd Society for the Study of Behavioural Phenotypes (SSBP) International Research Symposium in Birmingham, UK.