Our clinicians
The clinicians behind every assessment.
Every MAPP assessment is designed, led and overseen by the clinicians on this page. Their credentials are stated plainly, so you know exactly who you will be working with. Everyone who works with us works or has worked in autism assessment services, and is thoroughly vetted.
Dr Jason Crabtree
Co-Founder · Consultant Clinical Psychologist
HCPC registration PYL03919 · DClinPsy, PhD, MSc, BSc · Chartered Psychologist (CPsychol) · Associate Fellow of the British Psychological Society (AFBPsS)
Jason is a Consultant Clinical Psychologist with over 20 years’ experience working with autistic adults. He has developed and led NHS adult autism diagnostic and post-diagnostic services, primarily in north London.
He is Clinical Director of the Doctorate in Clinical Psychology at University College London, and has taught on autism and psychological therapy at UCL, the University of East London, and on the University of Birmingham’s Masters in Autism course.
Jason is an active researcher. He has presented on autism at national and international conferences and co-authored research papers in peer-reviewed journals. He served with the National Autistic Society Accreditation Programme for more than ten years, as an accreditation team member, team leader and panel member.
Jason cares about outcomes for autistic people in the broadest sense: psychological wellbeing, and access to every part of life that supports it.
Dr Catherine Cheung
Co-Founder · Principal Clinical Psychologist
HCPC registration PYL32865 · DClinPsy (UCL), MSc, BSc (Hons)
Catherine is a Principal Clinical Psychologist and leads a specialist NHS adult autism service in central London. She completed her BSc in Psychology, her MSc in Cognitive and Decision Sciences, and her Doctorate in Clinical Psychology at University College London.
Catherine has two decades of experience working with autistic and neurodivergent individuals and their families. She is formally trained in autism diagnostic assessment (ADOS-2, ADI-R), adult ADHD assessment (DIVA-5) and cognitive assessment (WAIS-IV), and in adapting evidence-based psychological therapies for autistic and ADHD adults. Her particular expertise is in the presentation of autism in women, in late-diagnosed adults, in high-achieving individuals, and in people who mask their autistic traits. Her work is neuroaffirmative and strengths-based, in the NHS and at MAPP alike.
Before her current roles, Catherine worked across NHS inpatient, community and research settings, with people navigating complex mental health needs, physical and neurological health conditions, and neurodevelopmental differences.
Catherine is committed to holistic, individualised work: understanding each person through their life experiences, cultural and social contexts, strengths and values, and thinking beyond diagnostic labels. Together with her clients, she carefully understands their life stories, holding different potential explanations and perspectives in mind. She works in English, Cantonese and Mandarin, and works sensitively across cultural, ethnic and social backgrounds.
Begin
Start with a conversation.
Tell us a little about yourself and what has brought you here. A senior clinician replies in writing within two business days.