Why Is ADHD Underdiagnosed in Girls but Overdiagnosed in Boys? 

The ADHD gender diagnosis gap reflects a longstanding imbalance in how the condition is recognised across sexes. Boys are more likely to be diagnosed, sometimes prematurely, while girls are often overlooked entirely. This is not because ADHD is less common in girls, but because it often looks different, and those differences are frequently missed. 

One major reason for the gap is the inattentive presentation of ADHD, which is more common in girls. Unlike the classic hyperactive symptoms often seen in boys, girls with ADHD may appear quiet, daydreamy, or emotionally sensitive. These behaviours are less likely to disrupt a classroom or draw concern, leading to delayed or missed diagnosis. 

Understanding the Sex Differences Behind the Diagnosis Gap 

External vs Internal Symptoms  

Boys more often exhibit external behaviours like fidgeting, blurting out answers, or acting impulsively, traits that prompt quicker referrals. Girls, however, may struggle silently with organisation, focus, or emotional overwhelm, which can be mistaken for shyness or anxiety rather than ADHD. 

Diagnostic Criteria Bias  

Traditional diagnostic frameworks were developed primarily using male-dominated samples, meaning they do not always reflect how ADHD manifests in girls. This contributes to the sex differences in recognition and diagnosis. 

Impact of Misdiagnosis and Missed Diagnosis 

 While boys face the risk of overdiagnosis, girls are more likely to go without support, leading to increased rates of anxiety, depression, and low self-esteem later in life due to untreated ADHD. 

Closing the ADHD gender diagnosis gap starts with awareness. Clinicians, teachers, and parents must be trained to recognise the full spectrum of ADHD symptoms across all genders. For more tailored support, visit providers like ADHD Certify for personalised consultations.

For a deeper dive into ADHD diagnosis and treatment, read our complete guide to Mislabelling Behavioral Issues as ADHD.