Challenges in diagnosing attention-deficit/hyperactivity disorder in pediatric practice: A regional and global perspective

Table 1 Comparison of Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and International Classification of Diseases, 11^th Revision diagnostic criteria for attention-deficit/hyperactivity disorder

Feature	Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (American Academy of Pediatrics, 2013)	International Classification of Diseases, 11th Revision (World Health Organization, 2022)
Disorder name	Attention-deficit/hyperactivity disorder (ADHD)	Attention deficit hyperactivity disorder (ADHD)
Classification	Neurodevelopmental disorders	Neurodevelopmental disorders
Core symptom domains	Inattention, hyperactivity/impulsivity (two domains)	Inattention, hyperactivity/impulsivity (two domains)
Subtypes/presentations	Three presentations: Predominantly Inattentive; predominantly hyperactive/impulsive; combined	No subtypes; describes severity of symptoms and predominant pattern
Symptom criteria	≥ 6 symptoms (children)/≥ 5 (adolescents/adults) in each domain lasting ≥ 6 months	At least several symptoms from both domains are required (no strict numeric threshold)
Age of onset	Symptoms must be present before age 12	Symptoms must begin during the developmental period, typically before age 12
Impairment requirement	Symptoms must cause clear impairment in social, academic, or occupational functioning	Symptoms must interfere with personal, family, social, educational, or occupational life
Cross-situational presence	Symptoms must be present in two or more settings	Symptoms must be evident in more than one context
Comorbidity approach	Allows ADHD diagnosis with ASD and other psychiatric conditions	Also allows ADHD with comorbid conditions, including ASD
Severity specifiers	Mild, moderate, severe based on the number and impact of symptoms	Descriptive text is used to indicate severity and functional impact
Emphasis	Symptom count and strict threshold adherence	Clinical judgment, functional impairment, and contextual factors

Table 1 shows that the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition is more quantitative and structured, using specific symptom counts and subtypes. In contrast, the International Classification of Diseases, 11^th Revision (ICD-11) adopts a more clinician judgment-based approach, emphasizing functional impairment without strict numeric thresholds. Both systems now recognize comorbidity with autism spectrum disorder, which was not allowed in earlier ICD versions. ADHD: Attention-deficit/hyperactivity disorder; ASD: Autism spectrum disorder.

Table 2 Attention-deficit/hyperactivity disorder symptoms vs common mimicking conditions

Attention-deficit/hyperactivity disorder symptom/feature	Possible mimicking conditions	Key differentiating features
Inattention	Learning disabilities (e.g., dyslexia, auditory processing disorder); absence seizures; depression	Learning disabilities often show specific academic skill deficits; absence seizures involve brief staring spells with no awareness; depression may show inattention with low mood and anhedonia
Hyperactivity	Anxiety disorders; ASD; sensory processing disorder	Anxiety often causes fidgeting from internal distress, not impulsivity; ASD may involve repetitive behaviors and poor social reciprocity; sensory issues are context-dependent and linked to specific stimuli
Impulsivity	Bipolar disorder; ODD; normal developmental behavior in preschoolers	Bipolar disorder includes episodic mood elevation and risk-taking; ODD involves deliberate defiance rather than spontaneous impulsivity; preschool impulsivity often improves with age and structure
Difficulty sustaining attention	Sleep disorders (e.g., obstructive sleep apnea, insufficient sleep); trauma and PTSD	Sleep disorders show fatigue, snoring, and poor morning arousal; PTSD may include hypervigilance, intrusive thoughts, and avoidance
Poor academic performance	Intellectual disability; specific learning disorders; environmental neglect	Intellectual disability involves global developmental delay; learning disorders are subject-specific; environmental factors often improve with intervention
Behavioral problems in school	Language disorders; hearing impairment; conduct disorder	Language/hearing issues lead to frustration-based behaviors; conduct disorder involves intentional aggression and rule-breaking

ASD: Autism spectrum disorder; ODD: Oppositional defiant disorder; PTSD: Post-traumatic stress disorder.

Table 3 Common rating scales used in attention-deficit/hyperactivity disorder assessment

Rating scale	Target informants	Purpose	Age group	Common use setting	Strengths	Limitations
Vanderbilt ADHD diagnostic rating scale	Parents, teachers	Symptom assessment and impairment screening; aligned with DSM criteria	6-12 years	Primary care, pediatrics	Freely available; easy to administer; covers ADHD and comorbidities (ODD, anxiety, etc.)	Limited depth; may be less sensitive in older adolescents; relies on subjective reports
Conners Comprehensive Behavior Rating Scales	Parents, teachers, youth	Detailed behavioral profiling, ADHD symptoms, and comorbid conditions	6-18 years	Specialized clinics, research	Comprehensive; validated for multiple disorders; norm-referenced	Requires purchase; time-consuming; may be impractical in busy primary care settings
ADHD rating scale-5	Parents, teachers	Frequency-based symptom rating aligned with DSM-5	5-17 years	Pediatric/psychology clinics	Updated for DSM-5; relatively quick to administer; standardized scoring	Focused solely on ADHD; does not assess broader behavioral issues
Swanson, Nolan, and Pelham Questionnaire (version IV)	Parents, teachers	Screens for ADHD and ODD	6-18 years	School and clinical settings	Freely accessible; based on DSM-IV; includes ODD items	Slightly outdated (DSM-IV); limited coverage of impairment
Strengths and difficulties questionnaire	Parents, teachers, self	Broad behavioral and emotional screening including attention problems	4-17 years	Schools, research, screening	Brief; assesses strengths as well as difficulties; available in many languages	Less specific for ADHD; may miss subtleties in symptom severity
CBCL	Parents	Comprehensive behavioral and emotional problem screening	6-18 years	Mental health and research	Strong psychometric properties; assesses broad psychopathology	Requires purchase and scoring software; not ADHD-specific
Teacher report form	Teachers	Teacher’s view of behavior; complements CBCL	6-18 years	Schools, research	Valuable classroom perspective; standardized tool	Limited to teacher input; not ideal for initial screening alone

ADHD: Attention-deficit/hyperactivity disorder; CBCL: Child behavior checklist; DSM: Diagnostic and Statistical Manual of Mental Disorders; ODD: Oppositional defiant disorder.

Table 4 Red flags suggesting alternative or additional diagnoses in attention-deficit/hyperactivity disorder evaluation

Red flag	Possible alternative/comorbid diagnosis	Clinical considerations
Global developmental delay or speech-language regression	ASD, intellectual disability	Consider formal developmental assessment; atypical social interaction or communication delays may indicate ASD rather than ADHD
Sudden onset of attention issues or behavioral changes	Trauma, acute stress reaction, seizure disorder	Explore psychosocial history, trauma exposure, or neurologic causes (e.g., seizures or head injury)
Nighttime symptoms (e.g., restlessness, tiredness in day)	Sleep disorders (e.g., obstructive sleep apnea, restless legs syndrome)	Sleep studies or ear, nose, and throat referral may be needed; ADHD-like symptoms can result from poor sleep quality
Severe mood swings, irritability, or aggression	Pediatric bipolar disorder, disruptive mood dysregulation disorder	Consider psychiatric referral; ADHD rarely causes episodic rage or mood lability independent of context
Excessive worry, fearfulness, or physical complaints	Anxiety disorders	Anxiety can lead to poor attention and school avoidance; distinguish internalizing symptoms from inattentiveness
Social withdrawal, anhedonia, poor appetite or sleep	Depression	Mood screening is warranted if signs of low motivation, fatigue, or sadness dominate
Academic difficulties in reading, writing, or math only	Specific learning disorders	Targeted psychoeducational testing may be needed to rule out dyslexia, dysgraphia, or dyscalculia
Oppositional or defiant behavior predominates	ODD, conduct disorder	Consider whether attention problems are secondary to behavior regulation or environmental issues
Seizure-like episodes, staring spells	Absence seizures, epilepsy	Neurology consult or electroencephalography may be indicated; brief inattentive spells could be seizure activity
Hallucinations, paranoia, disorganized thinking	Early-onset psychosis	Rare in children; prompt psychiatric evaluation is critical

ADHD: Attention-deficit/hyperactivity disorder; ASD: Autism spectrum disorder; ODD: Oppositional defiant disorder.

Table 5 Challenges faced by pediatricians in attention-deficit/hyperactivity disorder diagnosis

Problem	Key challenge	Description
Symptom overlap with other conditions	Overlapping presentations with other disorders	ADHD symptoms may resemble or coexist with conditions like autism spectrum disorder, anxiety, depression, learning disabilities, sleep disorders, or trauma, complicating differential diagnosis
Subjectivity in assessment	Reliance on subjective reports	Diagnosis depends heavily on parental and teacher observations, which can vary due to bias, setting (home vs school), and lack of objective behavioral tools
Cultural and societal influences	Influence of social norms and stigma	Cultural expectations may lead to misinterpretation of normal behaviors; stigma may delay help-seeking, and gender biases may result in underdiagnosis in girls
Parental and teacher bias	Inconsistent or biased reporting	Emotional, cultural, or educational factors can lead to under-reporting or over-reporting by parents and teachers, leading to diagnostic ambiguity
Time constraints and limited training	Limited time and inadequate behavioral training	Short consultation times and variable ADHD training during residency limit pediatricians’ ability to conduct detailed developmental assessments
Lack of access to multidisciplinary evaluation	Systemic barriers to specialist referral and evaluation	Long waitlists, fragmented pathways, geographic and financial disparities, and high pediatric workloads hinder access to comprehensive ADHD assessment

ADHD: Attention-deficit/hyperactivity disorder.

Table 6 Symptom overlap between attention-deficit/hyperactivity disorder and common mimicking/co-occurring conditions

Condition	Overlapping symptoms with attention-deficit/hyperactivity disorder	Distinguishing features
Autism spectrum disorder	Inattention, impulsivity, hyperactivity, social difficulties	Restricted/repetitive behaviors, impaired social communication, sensory sensitivities, poor non-verbal cues, early developmental delays
Anxiety disorders	Restlessness, inattention, fidgeting, irritability	Worry, somatic complaints, symptoms worsen in specific situations, avoidance behavior, sleep disturbance tied to fear
Depression	Poor concentration, low motivation, irritability, social withdrawal	Anhedonia, persistent sadness, low energy, appetite/sleep changes, feelings of worthlessness
Learning disabilities (e.g., dyslexia)	Inattention, academic underachievement, task avoidance	Difficulty in specific academic domains (e.g., reading/spelling/math), performance improves with support, frustration limited to academic tasks
Sleep disorders (e.g., obstructive sleep apnea, insomnia)	Inattention, hyperactivity, emotional dysregulation	Snoring, restless sleep, daytime fatigue, symptoms improve with sleep correction, abrupt symptom onset
Oppositional defiant disorder	Impulsivity, defiance, difficulty following instructions	Intentional defiance, argumentative behavior, irritability toward authority, behavior mainly situational
Trauma/post-traumatic stress disorder	Inattention, irritability, hypervigilance, sleep problems	History of trauma, intrusive thoughts, avoidance behaviors, exaggerated startle response, emotional numbing

Table 7 Practice implications of delayed or inaccurate attention-deficit/hyperactivity disorder diagnosis

Consequences of delayed ADHD diagnosis
Misdiagnosed ADHD often presents as academic failure and behavioral issues
Delays increase family stress and disrupt home dynamics
Risk of comorbidities (e.g., anxiety, depression, oppositional defiant disorder) rises with untreated ADHD
Missed early intervention leads to entrenched symptoms and harder treatment
Accurate, timely diagnosis improves outcomes across education, behavior, and mental health

ADHD: Attention-deficit/hyperactivity disorder.