Updated on
February 26, 2026
|
February 26, 2026
Compare overlapping symptoms of ADHD, autism, PDA, ODD and SpLD across six classroom domains. Interactive matrix helps SENCOs distinguish conditions and build APDR evidence for referral.
A Year 4 pupil stares out the window during carpet time. He fidgets, interrupts, and avoids writing tasks. His teacher suspects ADHD. The SENCO notices he also struggles with unstructured break times and becomes distressed by changes to routine. That looks more like autism. His parents report extreme demand avoidance at home, where he uses charm and distraction to escape tasks. Now PDA enters the picture.
This scenario plays out in thousands of UK classrooms every week. Teachers observe behaviours but lack a structured framework for distinguishing which condition drives which presentation. The reality is that neurodevelopmental conditions share symptoms. A child who "can't sit still" might have ADHD, autism, or both. A child who refuses tasks might have ODD, PDA, or an unidentified specific learning difficulty causing avoidance.
Neurodevelopmental conditions share neurological roots. The prefrontal cortex, which governs executive function, attention emotional regulation, and impulse control, develops atypically across ADHD, autism, and PDA profiles (Kern et al., 2015). sensory processing differences cut across all five conditions discussed here. And emotional dysregulation, once considered unique to ADHD, appears in virtually every neurodevelopmental profile when environmental demands exceed the child's capacity to cope.
The DSM-5 removed the diagnostic exclusion that previously prevented dual ADHD-autism diagnoses (American Psychiatric Association, 2013). This single change acknowledged what teachers had long observed: conditions cluster. A meta-analysis by Rommelse et al. (2010) found shared genetic factors between ADHD and ASD, with siblings of autistic children showing elevated ADHD traits at three times the population rate.
For SENCOs, this clustering creates a practical challenge. Standard referral pathways are condition-specific. A CAMHS referral for ADHD follows one route. An autism assessment follows another. If the child also presents with demand avoidance, a third conversation begins. The Symptom Overlap Matrix below helps you map what you observe before deciding where to refer.
Understanding each condition's core features helps SENCOs distinguish overlapping presentations in the classroom.
| Condition | Core Feature | What You See in the Classroom |
|---|---|---|
| Autism (ASD) | Differences in social communication and restricted/repetitive patterns | Misses social cues, prefers routine, intense topic focus, sensory sensitivity, literal interpretation of language |
| ADHD | Persistent inattention, hyperactivity, and impulsivity | Fidgets, blurts out answers, loses equipment, struggles with sustained focus, seeks novelty |
| PDA Profile | Extreme avoidance of everyday demands driven by anxiety | Uses social strategies (charm, distraction, excuses) to avoid tasks, appears socially capable but controlling, extreme emotional responses to perceived demands |
| ODD | Pattern of angry/irritable mood, argumentative behaviour, vindictiveness | Deliberately annoys others, refuses adult requests, blames others, loses temper frequently |
| SpLD | Specific difficulties with reading, writing, maths, or motor coordination | Written output below verbal ability, avoids reading aloud, inconsistent performance, slow processing, reversals in writing |
Each condition has a recognisable core. The difficulty begins when a child presents features from two or three columns simultaneously, which research suggests is more common than presenting with a single "clean" diagnosis.
Classroom behaviours that teachers observe fall into six observable domains. Within each domain, symptoms frequently cross condition boundaries.
Social difficulties appear across multiple conditions, but the underlying mechanism differs. An autistic child may struggle to read facial expressions because of differences in social cognition (Baron-Cohen, 1997). A child with ADHD may miss social cues because they were not attending when the cue occurred. A child with a PDA profile may appear socially skilled in one-to-one interactions but struggle in group settings where demands increase.
What the teacher sees: A pupil who talks over others during group work, stands too close to peers, or gives responses that seem unrelated to the conversation topic. All three conditions produce this behaviour, but the cause is different each time.
How to distinguish: Track whether the social difficulty is consistent (ASD) or variable depending on interest and arousal levels (ADHD). If the child uses sophisticated social strategies to avoid demands but struggles with genuine reciprocal friendship, consider PDA.
Inattention is the symptom most commonly attributed to ADHD, yet it appears across every condition in this guide. Autistic children may appear inattentive during whole-class teaching but sustain deep focus on preferred topics for hours. Children with SpLD may "zone out" during reading because the cognitive load of decoding leaves no capacity for comprehension.
What the teacher sees: A pupil who stares out the window during teacher exposition but produces detailed artwork during free choice time.
How to distinguish: Map the pattern. If inattention is task-specific and worst during reading/writing, investigate SpLD first. If inattention is pervasive across all contexts but improves dramatically with novelty, ADHD is more likely. If attention is intense but narrow, focused exclusively on the child's interests, autism is the stronger fit.
Meltdowns, shutdowns, and emotional outbursts occur across ASD, ADHD, PDA, and ODD. The trigger and recovery pattern differ.
An autistic meltdown is typically triggered by sensory overload or unexpected change and follows a predictable build-up (Mazefsky et al., 2013). The child may not respond to verbal de-escalation during the crisis. An ADHD-related emotional outburst tends to be impulsive, triggered by frustration or perceived unfairness, and resolves quickly once the frustration passes. PDA-driven distress escalates specifically around demands and may present as panic rather than anger. ODD-related defiance tends to be directed at specific adults and persists beyond the immediate trigger.
What the teacher sees: A child who throws a chair during a maths lesson.
How to distinguish: Ask three questions: (1) Was there a sensory or routine trigger? (ASD) (2) Was the child asked to do something? (PDA) (3) Is this behaviour targeted at a specific adult and sustained? (ODD) (4) Did it resolve within minutes once the frustration passed? (ADHD)
Sensory processing differences are formally recognised as part of the autism diagnostic criteria (DSM-5) but also appear in ADHD (Ghanizadeh, 2011), DCD/dyspraxia (within SpLD), and PDA profiles. A child who covers their ears during fire alarms might be autistic, or they might have ADHD with sensory over-responsivity, which recent research suggests affects up to 60% of children with ADHD.
What the teacher sees: A pupil who refuses to wear the school jumper, complains about classroom lighting, or becomes distressed in the dinner hall.
How to distinguish: Sensory difficulties that are consistent across settings and linked to specific modalities (always auditory, or always tactile) point toward ASD. Sensory difficulties that fluctuate with emotional state and arousal suggest ADHD. If sensory complaints increase specifically when demands are attached ("put your jumper on for PE"), consider whether demand avoidance is driving the apparent sensory difficulty.
Executive function encompasses planning, organising, task initiation, working memory, and cognitive flexibility. Deficits appear in every condition discussed here, making this the domain with the highest overlap.
An ADHD presentation typically shows deficits in inhibition and working memory (Barkley, 2012). Autistic executive function difficulties tend to cluster around cognitive flexibility and set-shifting (Hill, 2004). PDA profiles show intact executive function when self-directed but significant difficulty when executive demands are placed by others. SpLD executive function difficulties are often secondary to the cognitive load of compensating for the underlying learning difficulty.
What the teacher sees: A pupil who cannot start an essay despite understanding the topic, loses their PE kit weekly, and cannot sequence a multi-step science experiment.
How to distinguish: If the child can plan and organise activities they have chosen but falls apart with adult-directed tasks, consider PDA. If executive difficulties are worst during literacy/numeracy, investigate SpLD. If difficulties are pervasive regardless of task type or interest, ADHD or ASD are more likely.
Academic underperformance can mask neurodevelopmental conditions or be masked by them. A highly intelligent autistic child may achieve age-related expectations while struggling enormously with the social and sensory demands of the classroom. A child with dyslexia may develop behavioural difficulties that lead to an ODD or ADHD referral, while the underlying reading difficulty remains unidentified.
What the teacher sees: A pupil whose written work is dramatically below their verbal ability, or a pupil who achieves well in tests but refuses to complete classwork.
How to distinguish: Compare standardised test scores with classroom output. A significant gap between verbal reasoning and written production suggests SpLD. High capability with task refusal points toward PDA or demand-related anxiety. Inconsistent performance that varies day-to-day (rather than task-to-task) is characteristic of ADHD.
The interactive tool below allows you to select two or three conditions and compare their overlapping symptoms across all six domains. Select the conditions you are considering for a specific pupil, and the matrix will highlight which symptoms are shared and which are unique to each condition.
Symptom Overlap Matrix
Select two or three conditions below to compare overlapping symptoms across six classroom domains. Download the PDF comparison as evidence for your APDR cycle.
After using the matrix, download the PDF comparison as evidence for your Assess-Plan-Do-Review cycle. The output provides a structured record of your observations that can accompany a referral to educational psychology or CAMHS.
The SEND Code of Practice (DfE, 2015) requires schools to follow a Graduated Approach before seeking external assessment. The symptom overlap framework fits directly into this cycle.
| APDR Stage | What You Do | Tool to Use |
|---|---|---|
| Assess | Structured classroom observation across 6 domains for 2-4 weeks | Symptom Overlap Matrix (above) |
| Plan | Identify likely conditions and plan targeted classroom adjustments | Differentiation guidance from the matrix, condition-specific strategy cards |
| Do | Implement adjustments for 6-8 weeks, tracking frequency and intensity of target behaviours | Behaviour tracking sheets, ABC charts |
| Review | Compare pre- and post-intervention data; decide whether to continue, adjust, or escalate | Symptom Overlap Matrix re-assessment + PDF comparison |
Refer to educational psychology or CAMHS when:
The structured evidence from the Symptom Overlap Matrix strengthens your referral because it demonstrates to external professionals that school-level assessment has been systematic and thorough. Educational psychologists report that referrals accompanied by structured observational data lead to faster, more accurate assessments (Frederickson & Cline, 2015).
Symptom overlap becomes even more complex when masking is considered. Autistic girls are diagnosed on average 1.8 years later than autistic boys (Begeer et al., 2013), partly because they learn to copy the social behaviours of neurotypical peers. A girl who appears socially competent in class but experiences daily meltdowns at home may be masking her autism. If the SENCO only observes school behaviour, the presentation may look like anxiety or, in some cases, ODD.
ADHD in girls also presents differently to the stereotypical hyperactive boy. Girls with ADHD are more likely to present with inattentive subtype: daydreaming, disorganisation, and quiet underperformance rather than disruptive behaviour (Hinshaw et al., 2022). These presentations are frequently overlooked until secondary school, when academic demands increase and compensatory strategies fail.
When using the Symptom Overlap Matrix, consider whether the child's presentation at school matches reports from home. A significant gap between the two settings is itself a diagnostic indicator, often pointing toward masking in one environment.
This week: Choose one pupil whose presentation puzzles you. Use the Symptom Overlap Matrix to compare the two or three conditions you suspect. Download the PDF and file it in the pupil's SEND record.
This half-term: Share the matrix with your teaching staff during a SEND twilight session. Walk through the six domains and discuss how to distinguish overlapping presentations using the "how to tell the difference" guidance.
This term: Audit your current SEND register. For pupils with a single identified need, check whether their classroom presentation suggests co-occurring conditions that may have been overlooked. The SEND Code of Practice encourages schools to review and update assessments as new information emerges.
The conditions discussed in this article are not discrete categories. They are overlapping spectra, and the children who sit in your classrooms deserve professionals who understand the full complexity of what they observe. The Symptom Overlap Matrix provides the structured framework to move from "I think it might be ADHD" to "here is the systematic evidence for what I observe, and here is what distinguishes it from the alternatives."
Use this free, interactive tool to compare overlapping traits across ADHD, autism, PDA, ODD, and specific learning difficulties. No student data is stored.
Compare shared and unique symptoms across conditions
Select at least two conditions above to compare their symptoms side by side.
These peer-reviewed papers provide the evidence base for the symptom overlap framework discussed above.
Unraveling the Spectrum: Overlap, Distinctions, and Nuances of ADHD and ASD in Children View study ↗
Recent review
Bhat et al. (2024)
Comprehensive review examining the neurological and behavioural overlap between ADHD and ASD, with particular attention to shared executive function deficits and implications for classroom-based identification.
ADHD and Comorbid Disorders in Childhood Psychiatric Problems, Medical Problems, Learning Disorders, and Developmental Coordination Disorder View study ↗
92 citations
Leitner (2014)
Examines the high co-occurrence rates between ADHD and other neurodevelopmental conditions, finding that 50-70% of autistic children meet ADHD criteria. Directly relevant to understanding why teachers see overlapping presentations.
The Structure of Shared Genetic and Environmental Risk Factors for ADHD and ASD View study ↗
248 citations
Rommelse et al. (2010)
Landmark twin study demonstrating shared genetic factors between ADHD and autism, explaining why conditions cluster within families and within individual children. Foundational for understanding why overlap is the rule, not the exception.
Emotion Dysregulation in Autism Spectrum Disorder View study ↗
380 citations
Mazefsky et al. (2013)
Demonstrates that emotional dysregulation is pervasive in autism, not just ADHD, challenging the assumption that meltdowns indicate ADHD. Provides the framework for distinguishing autism-related emotional crises from ADHD-related impulsivity.
The Newborn Individualized Developmental Care and Assessment Program (NIDCAP) with Special Reference to Executive Function Deficits in ADHD View study ↗
Foundational
Barkley (2012)
The definitive model of executive function deficits in ADHD, distinguishing ADHD-type executive dysfunction (inhibition-based) from autism-type executive dysfunction (flexibility-based). Essential for understanding why both conditions affect planning and organisation but in different ways.
A Year 4 pupil stares out the window during carpet time. He fidgets, interrupts, and avoids writing tasks. His teacher suspects ADHD. The SENCO notices he also struggles with unstructured break times and becomes distressed by changes to routine. That looks more like autism. His parents report extreme demand avoidance at home, where he uses charm and distraction to escape tasks. Now PDA enters the picture.
This scenario plays out in thousands of UK classrooms every week. Teachers observe behaviours but lack a structured framework for distinguishing which condition drives which presentation. The reality is that neurodevelopmental conditions share symptoms. A child who "can't sit still" might have ADHD, autism, or both. A child who refuses tasks might have ODD, PDA, or an unidentified specific learning difficulty causing avoidance.
Neurodevelopmental conditions share neurological roots. The prefrontal cortex, which governs executive function, attention emotional regulation, and impulse control, develops atypically across ADHD, autism, and PDA profiles (Kern et al., 2015). sensory processing differences cut across all five conditions discussed here. And emotional dysregulation, once considered unique to ADHD, appears in virtually every neurodevelopmental profile when environmental demands exceed the child's capacity to cope.
The DSM-5 removed the diagnostic exclusion that previously prevented dual ADHD-autism diagnoses (American Psychiatric Association, 2013). This single change acknowledged what teachers had long observed: conditions cluster. A meta-analysis by Rommelse et al. (2010) found shared genetic factors between ADHD and ASD, with siblings of autistic children showing elevated ADHD traits at three times the population rate.
For SENCOs, this clustering creates a practical challenge. Standard referral pathways are condition-specific. A CAMHS referral for ADHD follows one route. An autism assessment follows another. If the child also presents with demand avoidance, a third conversation begins. The Symptom Overlap Matrix below helps you map what you observe before deciding where to refer.
Understanding each condition's core features helps SENCOs distinguish overlapping presentations in the classroom.
| Condition | Core Feature | What You See in the Classroom |
|---|---|---|
| Autism (ASD) | Differences in social communication and restricted/repetitive patterns | Misses social cues, prefers routine, intense topic focus, sensory sensitivity, literal interpretation of language |
| ADHD | Persistent inattention, hyperactivity, and impulsivity | Fidgets, blurts out answers, loses equipment, struggles with sustained focus, seeks novelty |
| PDA Profile | Extreme avoidance of everyday demands driven by anxiety | Uses social strategies (charm, distraction, excuses) to avoid tasks, appears socially capable but controlling, extreme emotional responses to perceived demands |
| ODD | Pattern of angry/irritable mood, argumentative behaviour, vindictiveness | Deliberately annoys others, refuses adult requests, blames others, loses temper frequently |
| SpLD | Specific difficulties with reading, writing, maths, or motor coordination | Written output below verbal ability, avoids reading aloud, inconsistent performance, slow processing, reversals in writing |
Each condition has a recognisable core. The difficulty begins when a child presents features from two or three columns simultaneously, which research suggests is more common than presenting with a single "clean" diagnosis.
Classroom behaviours that teachers observe fall into six observable domains. Within each domain, symptoms frequently cross condition boundaries.
Social difficulties appear across multiple conditions, but the underlying mechanism differs. An autistic child may struggle to read facial expressions because of differences in social cognition (Baron-Cohen, 1997). A child with ADHD may miss social cues because they were not attending when the cue occurred. A child with a PDA profile may appear socially skilled in one-to-one interactions but struggle in group settings where demands increase.
What the teacher sees: A pupil who talks over others during group work, stands too close to peers, or gives responses that seem unrelated to the conversation topic. All three conditions produce this behaviour, but the cause is different each time.
How to distinguish: Track whether the social difficulty is consistent (ASD) or variable depending on interest and arousal levels (ADHD). If the child uses sophisticated social strategies to avoid demands but struggles with genuine reciprocal friendship, consider PDA.
Inattention is the symptom most commonly attributed to ADHD, yet it appears across every condition in this guide. Autistic children may appear inattentive during whole-class teaching but sustain deep focus on preferred topics for hours. Children with SpLD may "zone out" during reading because the cognitive load of decoding leaves no capacity for comprehension.
What the teacher sees: A pupil who stares out the window during teacher exposition but produces detailed artwork during free choice time.
How to distinguish: Map the pattern. If inattention is task-specific and worst during reading/writing, investigate SpLD first. If inattention is pervasive across all contexts but improves dramatically with novelty, ADHD is more likely. If attention is intense but narrow, focused exclusively on the child's interests, autism is the stronger fit.
Meltdowns, shutdowns, and emotional outbursts occur across ASD, ADHD, PDA, and ODD. The trigger and recovery pattern differ.
An autistic meltdown is typically triggered by sensory overload or unexpected change and follows a predictable build-up (Mazefsky et al., 2013). The child may not respond to verbal de-escalation during the crisis. An ADHD-related emotional outburst tends to be impulsive, triggered by frustration or perceived unfairness, and resolves quickly once the frustration passes. PDA-driven distress escalates specifically around demands and may present as panic rather than anger. ODD-related defiance tends to be directed at specific adults and persists beyond the immediate trigger.
What the teacher sees: A child who throws a chair during a maths lesson.
How to distinguish: Ask three questions: (1) Was there a sensory or routine trigger? (ASD) (2) Was the child asked to do something? (PDA) (3) Is this behaviour targeted at a specific adult and sustained? (ODD) (4) Did it resolve within minutes once the frustration passed? (ADHD)
Sensory processing differences are formally recognised as part of the autism diagnostic criteria (DSM-5) but also appear in ADHD (Ghanizadeh, 2011), DCD/dyspraxia (within SpLD), and PDA profiles. A child who covers their ears during fire alarms might be autistic, or they might have ADHD with sensory over-responsivity, which recent research suggests affects up to 60% of children with ADHD.
What the teacher sees: A pupil who refuses to wear the school jumper, complains about classroom lighting, or becomes distressed in the dinner hall.
How to distinguish: Sensory difficulties that are consistent across settings and linked to specific modalities (always auditory, or always tactile) point toward ASD. Sensory difficulties that fluctuate with emotional state and arousal suggest ADHD. If sensory complaints increase specifically when demands are attached ("put your jumper on for PE"), consider whether demand avoidance is driving the apparent sensory difficulty.
Executive function encompasses planning, organising, task initiation, working memory, and cognitive flexibility. Deficits appear in every condition discussed here, making this the domain with the highest overlap.
An ADHD presentation typically shows deficits in inhibition and working memory (Barkley, 2012). Autistic executive function difficulties tend to cluster around cognitive flexibility and set-shifting (Hill, 2004). PDA profiles show intact executive function when self-directed but significant difficulty when executive demands are placed by others. SpLD executive function difficulties are often secondary to the cognitive load of compensating for the underlying learning difficulty.
What the teacher sees: A pupil who cannot start an essay despite understanding the topic, loses their PE kit weekly, and cannot sequence a multi-step science experiment.
How to distinguish: If the child can plan and organise activities they have chosen but falls apart with adult-directed tasks, consider PDA. If executive difficulties are worst during literacy/numeracy, investigate SpLD. If difficulties are pervasive regardless of task type or interest, ADHD or ASD are more likely.
Academic underperformance can mask neurodevelopmental conditions or be masked by them. A highly intelligent autistic child may achieve age-related expectations while struggling enormously with the social and sensory demands of the classroom. A child with dyslexia may develop behavioural difficulties that lead to an ODD or ADHD referral, while the underlying reading difficulty remains unidentified.
What the teacher sees: A pupil whose written work is dramatically below their verbal ability, or a pupil who achieves well in tests but refuses to complete classwork.
How to distinguish: Compare standardised test scores with classroom output. A significant gap between verbal reasoning and written production suggests SpLD. High capability with task refusal points toward PDA or demand-related anxiety. Inconsistent performance that varies day-to-day (rather than task-to-task) is characteristic of ADHD.
The interactive tool below allows you to select two or three conditions and compare their overlapping symptoms across all six domains. Select the conditions you are considering for a specific pupil, and the matrix will highlight which symptoms are shared and which are unique to each condition.
Symptom Overlap Matrix
Select two or three conditions below to compare overlapping symptoms across six classroom domains. Download the PDF comparison as evidence for your APDR cycle.
After using the matrix, download the PDF comparison as evidence for your Assess-Plan-Do-Review cycle. The output provides a structured record of your observations that can accompany a referral to educational psychology or CAMHS.
The SEND Code of Practice (DfE, 2015) requires schools to follow a Graduated Approach before seeking external assessment. The symptom overlap framework fits directly into this cycle.
| APDR Stage | What You Do | Tool to Use |
|---|---|---|
| Assess | Structured classroom observation across 6 domains for 2-4 weeks | Symptom Overlap Matrix (above) |
| Plan | Identify likely conditions and plan targeted classroom adjustments | Differentiation guidance from the matrix, condition-specific strategy cards |
| Do | Implement adjustments for 6-8 weeks, tracking frequency and intensity of target behaviours | Behaviour tracking sheets, ABC charts |
| Review | Compare pre- and post-intervention data; decide whether to continue, adjust, or escalate | Symptom Overlap Matrix re-assessment + PDF comparison |
Refer to educational psychology or CAMHS when:
The structured evidence from the Symptom Overlap Matrix strengthens your referral because it demonstrates to external professionals that school-level assessment has been systematic and thorough. Educational psychologists report that referrals accompanied by structured observational data lead to faster, more accurate assessments (Frederickson & Cline, 2015).
Symptom overlap becomes even more complex when masking is considered. Autistic girls are diagnosed on average 1.8 years later than autistic boys (Begeer et al., 2013), partly because they learn to copy the social behaviours of neurotypical peers. A girl who appears socially competent in class but experiences daily meltdowns at home may be masking her autism. If the SENCO only observes school behaviour, the presentation may look like anxiety or, in some cases, ODD.
ADHD in girls also presents differently to the stereotypical hyperactive boy. Girls with ADHD are more likely to present with inattentive subtype: daydreaming, disorganisation, and quiet underperformance rather than disruptive behaviour (Hinshaw et al., 2022). These presentations are frequently overlooked until secondary school, when academic demands increase and compensatory strategies fail.
When using the Symptom Overlap Matrix, consider whether the child's presentation at school matches reports from home. A significant gap between the two settings is itself a diagnostic indicator, often pointing toward masking in one environment.
This week: Choose one pupil whose presentation puzzles you. Use the Symptom Overlap Matrix to compare the two or three conditions you suspect. Download the PDF and file it in the pupil's SEND record.
This half-term: Share the matrix with your teaching staff during a SEND twilight session. Walk through the six domains and discuss how to distinguish overlapping presentations using the "how to tell the difference" guidance.
This term: Audit your current SEND register. For pupils with a single identified need, check whether their classroom presentation suggests co-occurring conditions that may have been overlooked. The SEND Code of Practice encourages schools to review and update assessments as new information emerges.
The conditions discussed in this article are not discrete categories. They are overlapping spectra, and the children who sit in your classrooms deserve professionals who understand the full complexity of what they observe. The Symptom Overlap Matrix provides the structured framework to move from "I think it might be ADHD" to "here is the systematic evidence for what I observe, and here is what distinguishes it from the alternatives."
Use this free, interactive tool to compare overlapping traits across ADHD, autism, PDA, ODD, and specific learning difficulties. No student data is stored.
Compare shared and unique symptoms across conditions
Select at least two conditions above to compare their symptoms side by side.
These peer-reviewed papers provide the evidence base for the symptom overlap framework discussed above.
Unraveling the Spectrum: Overlap, Distinctions, and Nuances of ADHD and ASD in Children View study ↗
Recent review
Bhat et al. (2024)
Comprehensive review examining the neurological and behavioural overlap between ADHD and ASD, with particular attention to shared executive function deficits and implications for classroom-based identification.
ADHD and Comorbid Disorders in Childhood Psychiatric Problems, Medical Problems, Learning Disorders, and Developmental Coordination Disorder View study ↗
92 citations
Leitner (2014)
Examines the high co-occurrence rates between ADHD and other neurodevelopmental conditions, finding that 50-70% of autistic children meet ADHD criteria. Directly relevant to understanding why teachers see overlapping presentations.
The Structure of Shared Genetic and Environmental Risk Factors for ADHD and ASD View study ↗
248 citations
Rommelse et al. (2010)
Landmark twin study demonstrating shared genetic factors between ADHD and autism, explaining why conditions cluster within families and within individual children. Foundational for understanding why overlap is the rule, not the exception.
Emotion Dysregulation in Autism Spectrum Disorder View study ↗
380 citations
Mazefsky et al. (2013)
Demonstrates that emotional dysregulation is pervasive in autism, not just ADHD, challenging the assumption that meltdowns indicate ADHD. Provides the framework for distinguishing autism-related emotional crises from ADHD-related impulsivity.
The Newborn Individualized Developmental Care and Assessment Program (NIDCAP) with Special Reference to Executive Function Deficits in ADHD View study ↗
Foundational
Barkley (2012)
The definitive model of executive function deficits in ADHD, distinguishing ADHD-type executive dysfunction (inhibition-based) from autism-type executive dysfunction (flexibility-based). Essential for understanding why both conditions affect planning and organisation but in different ways.
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