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Adult ADHD Diagnostic Assessment

ADHD diagnostic assessments aim to build a clear, evidence-based understanding of an adult’s attention profile, executive functioning, and day-to-day needs. Our assessments are delivered in a structured and supportive way, helping individuals access appropriate treatment and support.

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Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental condition characterised by differences in attention regulation, activity levels, and impulse control that impact daily functioning across settings. Presentation can vary significantly between individuals and may change over time as demands increase.

What is ADHD?

An ADHD assessment may be helpful for adults who:

Struggle with attention, focus, or completing tasks
Find organisation, planning, or time management difficult
Experience restlessness or feel constantly “on the go”
Act impulsively in conversations, decisions, or spending
Feel overwhelmed managing everyday responsibilities

Who Are Assessments For

When an Assessment May Be Helpful

An ADHD assessment may be helpful when:

An adult has longstanding attention or organisational difficulties
Demands of work or daily life are becoming harder to manage
Challenges are affecting employment, relationships, or wellbeing
There are ongoing questions despite previous support or strategies
An individual wishes to explore diagnosis and treatment options

What the Assessment Involves

Step 01

Initial enquiry and screening begins with an initial enquiry and completion of screening questionnaires to understand presenting concerns and consider whether a full ADHD assessment is appropriate.
Step 02

Review and planning involves careful consideration of the information provided so that the assessment approach is tailored to the individual, and in some cases alternative recommendations may be made.
Step 03

Clinical diagnostic interview explores attention, impulsivity, activity levels, executive functioning, and the impact of these differences across education, employment, relationships, and day-to-day life.
Step 04

Developmental history focuses on how attention and behavioural differences have presented over time, helping to evidence the neurodevelopmental nature of ADHD.
Step 05

Clinical integration brings together information from interviews, questionnaires, and supporting evidence to inform diagnostic decision-making.
Step 06

Written report and feedback involves sharing a comprehensive diagnostic report, followed by a feedback appointment to discuss outcomes and recommendations.

Report Recognition & Professional Standards

Assessments at Seafield Psychology are conducted by HCPC-registered Clinical Psychologists and other appropriately registered professionals, including Registered Nurses and Speech and Language Therapists. All clinicians involved in the assessment process have several years of experience delivering neurodevelopmental assessments within NHS services.

Assessments are overseen by Dr Catriona Amberton, Clinical Director of Seafield Psychology and Team Lead for a commissioned autism diagnostic service in West Essex. This ensures that assessment processes mirror established NHS pathways in structure, governance and clinical standards.

Assessments are aligned with NICE guidance and are based on a comprehensive, multi-informant approach, incorporating clinical interview, developmental history and validated rating scales, with information gathered from relevant settings (for example home and school, where appropriate). Reports are suitable for sharing with schools, GPs, employers, local authorities and other professionals, and can support EHCP processes and requests for reasonable adjustments where appropriate.

Assessment may also inform decisions about behavioural strategies, educational adjustments, or onward referral where appropriate.

Waiting Times

Appointments are typically available within a few weeks of initial enquiry. Following completion of the assessment process, reports are usually provided within two to three weeks.

NHS waiting times for neurodevelopmental assessments can often extend to many months or longer. A private assessment can offer clarity and support sooner, allowing families to move forward with appropriate understanding and planning.