Are There Specific Medical Tests to Differentiate ADHD from Other Conditions? 

Diagnosing ADHD requires careful consideration of a child’s medical and behavioural history, as many other conditions can mimic its symptoms. Medical tests to diagnose ADHD play an important role in ruling out other potential causes for symptoms like inattention, impulsivity, and hyperactivity.  

Screening Tools for ADHD Diagnosis 

The first step in diagnosing ADHD is often the use of standardised screening tools. These tools include questionnaires and rating scales, such as the Conners Rating Scales or Vanderbilt Assessment Scales, which help clinicians assess the frequency and severity of ADHD symptoms.  

However, ADHD-like symptoms may also be present in children with other physical conditions, such as sleep disorders, hearing impairments, or thyroid problems. In such cases, medical tests are essential to rule out these conditions. For example, blood tests can be used to check for deficiencies in nutrients such as iron or vitamin B12, both of which can cause symptoms similar to ADHD. Thyroid function tests can help detect thyroid imbalances, which can lead to attention and behavioural issues. 

In addition to screening tools, a physical examination can be used to rule out other potential conditions like vision problems, seizure disorders, or neurological conditions, all of which can mimic ADHD symptoms. If medical conditions are suspected, further specialised tests may be recommended to confirm the diagnosis. 

While medical tests to diagnose ADHD are not used to directly confirm the condition, they are essential for differentiating ADHD from other physical conditions that share similar symptoms. A comprehensive evaluation ensures that individuals receive the correct diagnosis and appropriate treatment. 

Visit providers like ADHD Certify for personal consultations and expert guidance tailored to your unique situation. 

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Differential Diagnosis of ADHD.

Avery Lombardi, MSc

Author

Avery Lombardi is a clinical psychologist with a Master’s in Clinical Psychology and a Bachelor’s in Psychology. She has professional experience in psychological assessment, evidence-based therapy, and research, working with both child and adult populations. Avery has provided clinical services in hospital, educational, and community settings, delivering interventions such as CBT, DBT, and tailored treatment plans for conditions including anxiety, depression, and developmental disorders. She has also contributed to research on self-stigma, self-esteem, and medication adherence in psychotic patients, and has created educational content on ADHD, treatment options, and daily coping strategies.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy. 

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.