Separation Anxiety Disorder ICD-11 Diagnostic Requirements Explained
Updated: Oct 8
Author: Ukrainian Psychological Hub · Published: October 1, 2026 · Editorial Policy
In ICD-11, Separation Anxiety Disorder is coded 6B05. It is an anxiety or fear-related disorder defined by marked and excessive fear or anxiety about separation from specific people with whom the person has a deep emotional bond. The World Health Organization's 2024 ICD-11 Clinical Descriptions and Diagnostic Requirements is the primary clinical classification source for the requirements explained on this page.
The diagnosis is available across the lifespan. In children and adolescents, the focus commonly involves parents, caregivers, or other family members, and the fear must exceed what is developmentally normative. In adults, the focus commonly involves a spouse or romantic partner or the person's children. The current WHO ICD-11 2026 release retains Separation Anxiety Disorder as 6B05.
This page explains the ICD-11 diagnostic requirements. It does not treat ordinary separation distress, attachment anxiety, school refusal, panic attacks, a screening score, or worry about a loved one as a diagnosis by themselves. For the broader diagnostic family, see Anxiety Disorders: Symptoms, Types, Diagnosis, and Treatment and ICD-11 Anxiety Classification: Anxiety or Fear-Related Disorders.
ICD-11 separation anxiety disorder in one sentence
Separation Anxiety Disorder in ICD-11 is a persistent and clinically significant pattern in which separation from a deeply attached person becomes the central focus of excessive fear or anxiety, with manifestations shaped by developmental level and consequences that produce substantial distress, impairment, or functioning maintained only through significant additional effort.
What ICD-11 means by diagnostic requirements
ICD-11 clinical diagnosis is not a mechanical checklist in which one isolated symptom or one questionnaire score establishes a disorder. The CDDR identifies essential features, then asks clinicians to interpret them in developmental, cultural, medical, and psychiatric context. First and colleagues describe this ICD-11 approach as deliberately less dependent on arbitrary numerical thresholds than DSM-5 for many disorders, while still making the diagnostic concept explicit.
Within anxiety or fear-related disorders, a major organizing principle is the focus of apprehension: what the person fears will happen, and what object or situation organizes the anxiety. Kogan and colleagues describe this focus-of-apprehension framework as a central feature of the ICD-11 anxiety classification. For Separation Anxiety Disorder, the focus is separation from a specific attachment figure, not diffuse worry, social evaluation, inability to escape, or recurrent unexpected panic itself.
The clinical utility of the ICD-11 framework has been examined internationally. In a global case-controlled field study involving 1,840 mental health professionals, Rebello and colleagues found that clinicians using the proposed ICD-11 guidelines were significantly more accurate in diagnosing adult cases of Separation Anxiety Disorder than clinicians using ICD-10 guidelines.
A separate 13-country field study by Reed and colleagues found that clinicians generally rated ICD-11 guidelines as clear, understandable, easy to use, and useful for distinguishing disorders from normality and from other disorders. These findings support clinical utility; they do not turn the classification into a self-diagnosis tool.
ICD-11 code 6B05 and where the diagnosis belongs
The diagnostic code is 6B05. In ICD-11, Separation Anxiety Disorder belongs to the grouping Anxiety or fear-related disorders alongside Generalized Anxiety Disorder, Panic Disorder, Agoraphobia, Specific Phobia, Social Anxiety Disorder, and Selective Mutism. The WHO CDDR places these disorders in one lifespan-oriented grouping while preserving separate diagnostic territories.
This represents an important change from ICD-10. Separation anxiety was previously classified as Separation Anxiety Disorder of Childhood, F93.0, within disorders with onset specific to childhood. A 2025 review of the transition from ICD-10 to ICD-11 by Domschke and Zwanzger notes that the childhood-onset restriction was removed and the diagnosis was moved into the anxiety or fear-related grouping as 6B05.
The change matters clinically because an adult does not need to prove that the disorder began in childhood in order for the current ICD-11 diagnosis to be considered. Adult onset is possible.
The essential ICD-11 pattern
The diagnostic logic can be understood through five linked questions: Is the fear specifically about separation from a deeply attached person? Is the intensity excessive for the person's developmental and real-world context? Does it persist rather than appear as a brief reaction? Does it cause significant distress, impairment, or extraordinary effort to maintain functioning? And is another condition a better explanation?
1. The fear or anxiety centers on separation from an attachment figure
The core feature is marked and excessive fear or anxiety about separation from one or more specific attachment figures. The WHO CDDR describes these as people with whom the individual has a deep emotional bond.
The attachment figure is not defined by a single relationship label. In childhood, it may be a parent, caregiver, or another family member. In adulthood, the focus commonly shifts to a spouse or romantic partner or to children. The clinical question is whether separation from this person is the organizing focus of the fear.
2. Developmental context is part of the requirement
Separation distress is part of normal development, especially in younger children. ICD-11 therefore requires clinicians to judge whether the fear or anxiety is beyond what would be expected for the person's developmental level. The same behavior can carry different meaning at different ages.
For a dedicated boundary between developmentally expected separation distress and a clinical disorder, see Separation Anxiety vs Normal Separation Distress: What Is the Difference?.
A young child becoming distressed during an ordinary separation may be developmentally expected. Persistent separation fear that is markedly excessive, lasts for months, disrupts school or family life, and exceeds what is expected for that child's developmental stage is a different clinical pattern.
For adults, developmentally normative language remains relevant in a different way: close relationships naturally involve concern, grief at departures, and desire for proximity. Diagnosis depends on the pattern becoming excessive, persistent, and clinically consequential rather than on closeness itself.
3. Manifestations vary with age and situation
The WHO CDDR gives examples rather than a rigid symptom-count list. Manifestations can include persistent thoughts that harm or another untoward event will cause separation; reluctance or refusal to go to school or work; recurrent excessive distress when separation occurs; reluctance or refusal to sleep without the attachment figure nearby; recurrent nightmares about separation; and physical symptoms such as nausea, vomiting, stomach pain, or headache in separation-related situations.
These examples describe ways the same separation-focused fear can appear. A person does not need to display every example, and the presence of one example does not by itself establish the disorder.
The clinical common denominator is the separation focus. Refusing school because of fear of bullying, refusing work because of social evaluation, or avoiding travel because of fear of being unable to escape may look behaviorally similar while pointing to different diagnostic explanations.
4. The pattern must persist
ICD-11 states that the symptoms are not transient and persist for an extended period, giving at least several months as an example. This wording comes from the WHO CDDR and is also reflected in the current ICD-11 description of 6B05.
The phrase “at least several months” should not be replaced with a DSM rule. ICD-11 does not use the DSM-5-TR formulation of at least four weeks for children and adolescents and typically six months or more for adults. Those are DSM diagnostic criteria, not the ICD-11 duration wording.
Duration also has to be interpreted together with severity and context. A prolonged but mild preference for closeness is not converted into a disorder merely because it has lasted for months.
5. Distress, impairment, or major additional effort must be clinically significant
The WHO CDDR requires significant distress related to the persistent anxiety symptoms or significant impairment in personal, family, social, educational, occupational, or other important areas of functioning. It also recognizes a clinically important pattern in which functioning is maintained only through significant additional effort.
This means that visible failure is not the only marker of impact. A child may still attend school only because a caregiver spends hours negotiating every departure. An adult may continue working while arranging elaborate contact, reassurance, or proximity routines that consume substantial time and energy. The diagnosis still requires the whole ICD-11 pattern, not effort alone.
6. Another mental disorder must not explain the pattern better
ICD-11 requires that the symptoms are not better accounted for by another mental disorder. The CDDR gives agoraphobia and personality disorder as examples in the Separation Anxiety Disorder differential. This is why the feared outcome—the focus of apprehension—matters as much as the visible avoidance. See How Is Anxiety Diagnosed? Assessment, History, and Differential Diagnosis for the broader assessment process.
What “marked and excessive” means in practice
“Marked” refers to a clinically prominent level of fear or anxiety, while “excessive” requires context. The clinician considers developmental expectations, the actual probability and seriousness of separation-related threats, the person's environment, cultural practices, and whether the response is proportionate to those realities.
A child living through an unstable caregiving situation, a family facing an acute medical crisis, or a person whose partner is entering a genuinely dangerous environment may have intense separation-related fear for understandable reasons. The presence of strong emotion does not erase context.
Clinical assessment asks whether the anxiety remains disproportionate and organizes behavior in a persistent, impairing way once realistic circumstances are taken into account.
The focus of apprehension is the diagnostic hinge
The ICD-11 anxiety framework emphasizes what the person is actually afraid will happen. Kogan et al. describe this as a major method for differentiating anxiety and fear-related disorders.
In Separation Anxiety Disorder, the feared outcome is separation itself or events imagined to produce separation. Examples include fears that the attachment figure will be injured, die, disappear, be kidnapped, or otherwise become unavailable; fears that the individual will get lost or encounter an event that prevents reunion; or distress centered on being physically apart.
This differs from GAD, in which worry typically spans multiple life domains; agoraphobia, in which the concern centers on situations where escape may be difficult or help unavailable; social anxiety disorder, in which negative evaluation is central; and panic disorder, in which recurrent unexpected panic attacks and their consequences occupy the diagnostic territory.
Children and adolescents
ICD-11 explicitly preserves a developmental threshold for younger people. The presence of crying, clinging, requests for reassurance, bedtime resistance, or reluctance to separate does not by itself define a disorder. The clinician asks whether the pattern is beyond developmental expectations, persistent, and clinically significant.
School refusal is especially important to interpret correctly. It is a behavior, not a diagnosis. A child may avoid school because of separation fear, social anxiety, bullying, learning problems, depression, neurodevelopmental factors, physical illness, family stress, or other causes. Separation Anxiety Disorder is supported when separation from the attachment figure is the central source of the fear and the full ICD-11 requirements are met.
In younger children, separation distress may be expressed behaviorally rather than through elaborate verbal descriptions. Tantrums, social withdrawal, sleeping difficulties, nightmares, stomach pain, nausea, or headache can occur in the separation context. These manifestations still require contextual assessment and, where indicated, medical evaluation.
Information from caregivers and school can be clinically useful because the pattern may differ by setting. A child may appear comfortable at home while showing severe distress at school arrival, overnight activities, or any situation that removes access to the attachment figure.
Adults can meet ICD-11 requirements
Adult Separation Anxiety Disorder is not a contradiction in ICD-11. Research preceding the modern lifespan classification showed that clinically significant separation anxiety occurs in adults and may begin after childhood. A review by Bögels, Knappe, and Clark found that the older childhood-onset restriction was not supported by the available evidence and that adult presentations can be impairing and comorbid.
Cross-national data from 38,993 adults in 18 countries in the WHO World Mental Health Surveys found that a substantial proportion of estimated lifetime Separation Anxiety Disorder onsets occurred after age 18. Silove and colleagues reported 43.1% of estimated lifetime onsets after age 18 in that historical survey framework. These epidemiologic estimates predate the final ICD-11 CDDR and should not be read as current ICD-11 prevalence figures, but they helped establish the lifespan evidence base.
A clinical review by Baldwin and colleagues emphasizes that adult separation anxiety can be distinguished from other anxiety disorders by its attachment-specific focus and can occur alongside other psychiatric conditions.
Adult manifestations may include difficulty being apart from a partner or child, persistent fear that something catastrophic will cause separation, repeated reassurance or contact behaviors, reluctance to travel or sleep separately, or physical distress around departures. The same threshold rules apply: persistence, clinical significance, context, and differential diagnosis.
Does ICD-11 require a fixed number of symptoms?
No fixed count such as “three of eight symptoms” appears in the ICD-11 CDDR essential-feature formulation for 6B05. The WHO presents manifestations as examples within the required separation-focused pattern. First and colleagues identify Separation Anxiety Disorder as one of the conditions in which DSM-5 provides greater operational specificity than ICD-11.
This distinction matters for online content. Importing the DSM symptom count into an ICD-11 article creates a hybrid rule that belongs to neither system. ICD-11 diagnosis is based on the required clinical pattern, not a copied DSM checklist.
How long must separation anxiety last in ICD-11?
The ICD-11 answer is an extended period, with at least several months given as an example. Domschke and Zwanzger summarize this duration formulation in their comparison of ICD-10 and ICD-11 anxiety taxonomy.
The duration requirement prevents brief, situational, or transient separation reactions from being automatically classified as a disorder. It also leaves room for clinical judgment across developmental stages and contexts rather than imposing a different fixed cutoff for every age group.
A clinician still asks when the pattern began, whether it has been continuous or intermittent, whether its intensity changes by context, and whether impairment has persisted.
Physical symptoms and separation situations
The WHO CDDR specifically notes physical symptoms such as nausea, vomiting, stomach pain, and headache as possible manifestations when separation occurs or is anticipated. These symptoms may be especially visible in children, but physical anxiety symptoms can occur at any age.
A temporal association with separation can support the clinical formulation, but it does not prove that a physical symptom is caused by anxiety. New, severe, persistent, unexplained, or medically concerning symptoms require appropriate medical assessment rather than attribution to Separation Anxiety Disorder by coincidence alone.
The same principle is part of broader anxiety assessment: psychiatric diagnosis is made after history, context, and relevant differential possibilities are considered. See Anxiety Differential Diagnosis: What Can Look Like an Anxiety Disorder?.
Panic attacks and the 6B05/MB23.H qualifier
Panic attacks can occur in Separation Anxiety Disorder. The WHO CDDR allows the panic-attack qualifier when panic attacks occur in association with the disorder and there is no co-occurring Panic Disorder diagnosis. In the ICD-11 coding structure this can be represented as 6B05/MB23.H.
A panic attack is an acute episode of intense fear or discomfort with a cluster of physical and cognitive symptoms. It is not automatically Panic Disorder. If panic occurs only in separation-related situations, the separation focus remains diagnostically important.
Panic Disorder has its own ICD-11 requirements, centered on recurrent unexpected panic attacks and their consequences. For that territory, see Panic Disorder ICD-11 Diagnostic Requirements Explained.
The distinction is clinically useful because identical bodily sensations can participate in different disorders depending on their pattern, triggers, expectations, and course.
Differential diagnosis
Differential diagnosis asks what best explains the fear, avoidance, reassurance seeking, somatic symptoms, or reluctance to leave a familiar person. Similar-looking behavior can emerge from different clinical mechanisms.
Generalized Anxiety Disorder
GAD is organized around persistent generalized apprehension and worry across multiple domains rather than separation from a specific attachment figure. A person with Separation Anxiety Disorder may also worry about many things, but separation-related fear must remain the defining pattern for the 6B05 diagnosis.
For the ICD-11 GAD requirements, see GAD ICD-11 Diagnostic Requirements Explained.
Agoraphobia
Agoraphobia centers on multiple situations in which escape might be difficult or help unavailable if incapacitating, panic-like, or embarrassing symptoms occur. A person with Separation Anxiety Disorder may avoid leaving home, but the reason is attachment-related separation rather than the agoraphobic focus.
The two diagnoses therefore cannot be distinguished by “stays close to home” alone. See Agoraphobia ICD-11 Diagnostic Requirements Explained.
Panic Disorder
Separation-triggered panic does not by itself establish Panic Disorder. The clinician asks whether recurrent unexpected panic attacks occur independently of the separation focus and whether the broader Panic Disorder requirements are met.
Social Anxiety Disorder
Social Anxiety Disorder is defined around fear of negative evaluation in social situations. A child who refuses school because of fear of judgment has a different focus of apprehension from a child who refuses because separation from a caregiver feels intolerable.
For the ICD-11 social-anxiety requirements, see Social Anxiety Disorder ICD-11 Diagnostic Requirements Explained.
Specific Phobia
Specific Phobia is organized around a circumscribed object or situation. If the feared stimulus is dogs, flying, injections, or another specific cue, and separation from an attachment figure is secondary, the formulation may point away from Separation Anxiety Disorder.
For the ICD-11 specific-phobia requirements, see Specific Phobia ICD-11 Diagnostic Requirements Explained.
Selective Mutism
Selective Mutism concerns a consistent selectivity in speaking: the person has adequate language competence in some settings but consistently fails to speak in other situations where speaking is expected. Temporary silence during intense separation distress in a young child is not automatically Selective Mutism, and Selective Mutism remains its own ICD-11 diagnosis.
Mood disorders
Depressive states can produce withdrawal, reluctance to leave home, reduced school or work attendance, dependence on others, and pessimistic thoughts about loss. The diagnostic question is whether a separation-specific fear pattern meeting 6B05 is present or whether the behavior is better explained by a mood episode.
The ICD-11 MMS lists mood disorders among exclusions under 6B05, while the CDDR also notes that Separation Anxiety Disorder can co-occur with mood disorders in adults. These statements should be read in their clinical and coding context rather than as a claim that mood symptoms and separation anxiety can never coexist.
PTSD, prolonged grief, and stress-related conditions
Fear of losing an attachment figure can appear after trauma or bereavement. PTSD is organized around a traumatic event and its characteristic re-experiencing, avoidance, and threat-related pattern; prolonged grief disorder is organized around persistent grief following bereavement. Separation Anxiety Disorder is diagnosed on its own requirements and should not be used as a generic label for trauma- or grief-related distress.
Personality disorder and attachment anxiety
The CDDR explicitly names personality disorder as a possible alternative explanation. Baldwin and colleagues also discuss the clinical boundaries of adult separation anxiety. A broader, enduring pattern of self and interpersonal dysfunction may require personality-disorder assessment rather than being reduced to separation anxiety.
Attachment anxiety is a psychological construct used in attachment research and relationship psychology. It is not synonymous with the ICD-11 diagnosis Separation Anxiety Disorder. A person can have attachment-related insecurity without meeting 6B05, and a clinical diagnosis cannot be inferred from an attachment-style score.
Comorbidity does not erase diagnostic boundaries
The WHO CDDR notes that Separation Anxiety Disorder frequently co-occurs with other mental, behavioral, and neurodevelopmental disorders. In children and adolescents, common co-occurring conditions include Generalized Anxiety Disorder and Specific Phobia; in adults, mood disorders, other anxiety and fear-related disorders, PTSD, and personality disorder are among the commonly co-occurring conditions described.
Comorbidity means that more than one clinically meaningful pattern can exist at the same time. It does not mean every symptom should be assigned to every diagnosis. Each disorder still needs its own defining pattern and threshold.
This is particularly important with panic attacks. A panic attack can be specified within Separation Anxiety Disorder, while a separate Panic Disorder diagnosis requires its own pattern of recurrent unexpected attacks and associated consequences.
ICD-11 versus DSM-5-TR
ICD-11 and DSM-5-TR are closely aligned in recognizing Separation Anxiety Disorder across the lifespan, but they are not interchangeable. A systematic comparison by First and colleagues classifies Separation Anxiety Disorder among conditions where the systems are broadly similar but DSM-5 provides greater operational specificity.
Symptom count
DSM-5-TR uses a defined symptom-count structure. ICD-11 instead describes a required separation-focused clinical pattern and lists manifestations as examples. Do not import the DSM count into ICD-11.
Duration
DSM-5-TR specifies at least four weeks in children and adolescents and typically six months or more in adults. ICD-11 uses persistence over an extended period, for example at least several months. The official DSM source is the DSM-5-TR; the ICD formulation comes from the WHO CDDR.
Lifespan diagnosis
Both contemporary systems allow diagnosis in adults. This is a major departure from older systems that framed separation anxiety primarily as a childhood disorder.
Clinical judgment
ICD-11 places comparatively greater emphasis on the overall diagnostic concept, developmental and cultural context, clinical significance, and whether another disorder explains the presentation better. DSM-5-TR operationalizes the syndrome with a more explicit criteria set.
For the broader system-level comparison, see DSM-5-TR vs ICD-11 Anxiety Disorders: Key Classification Differences.
What changed from ICD-10 to ICD-11?
ICD-10 classified Separation Anxiety Disorder of Childhood as F93.0 and tied the diagnosis to childhood. ICD-11 moved the condition into the Anxiety or fear-related disorders grouping, renamed it Separation Anxiety Disorder, assigned code 6B05, and adopted a lifespan approach. Domschke and Zwanzger describe this as one of the notable structural changes in the anxiety taxonomy.
The change was not merely cosmetic. In the global case-controlled study by Rebello and colleagues clinicians using the ICD-11 guidelines were more accurate than those using ICD-10 in diagnosing adult Separation Anxiety Disorder cases.
The practical consequence is that clinicians are directed toward the actual current presentation and focus of apprehension rather than requiring a childhood-onset history before adult diagnosis can be considered.
Screening, questionnaires, and formal diagnosis
A questionnaire can measure separation-anxiety symptoms or severity. It cannot by itself establish ICD-11 6B05. Formal diagnosis requires clinical assessment of the attachment-specific focus, developmental context, duration, distress or impairment, differential diagnosis, and relevant medical and psychiatric context.
For adults, research instruments such as the Adult Separation Anxiety Questionnaire have been developed and psychometrically studied. The original questionnaire development paper by Manicavasagar and colleagues is available through its journal DOI. A high score can identify symptoms worth evaluating; it does not replace diagnosis.
The same distinction applies to parent-report or child anxiety scales. Screening asks whether further assessment may be useful. Diagnosis asks whether the full disorder requirements are met and whether another explanation fits better.
For a broader explanation of screening, history, and clinical assessment, see How Is Anxiety Diagnosed? Assessment, History, and Differential Diagnosis.
How a clinician may assess possible ICD-11 Separation Anxiety Disorder
A careful assessment usually begins with the presenting problem rather than the diagnostic label. The clinician clarifies who the attachment figure is, what separations trigger fear, what the person predicts will happen, and how they respond before, during, and after separation.
The clinician then establishes the time course: when the pattern began, whether it represents a recent reaction or a persistent condition, and whether it has lasted over the extended period expected by ICD-11.
Developmental context is assessed directly. In children and adolescents, the clinician considers age, developmental level, family practices, school expectations, and whether the reaction exceeds what would be normative. In adults, the clinician distinguishes intense but understandable relational concern from an excessive and impairing separation-focused syndrome.
Functional impact is examined across settings. School attendance, work, sleep, travel, independent activity, family routines, social life, and the amount of effort required to sustain ordinary functioning can all provide clinically relevant information.
Differential diagnosis then tests alternative explanations: broad worry, fear of panic or escape difficulty, social evaluation, circumscribed phobic cues, depression, trauma, grief, personality functioning, neurodevelopmental context, substance or medication effects, and medical causes of physical symptoms when relevant.
Collateral information from caregivers, partners, school staff, or other sources can be useful when appropriate, especially when the person is young or when the pattern differs substantially across settings.
Examples of the diagnostic boundary
Example: developmentally expected distress
A young child cries during the first days of a new childcare arrangement but settles after the caregiver leaves, gradually adapts, and continues normal play and sleep. The separation distress is real, yet the short-lived and developmentally expected pattern does not by itself indicate Separation Anxiety Disorder.
Example: possible childhood disorder
A school-age child has months of intense distress before school, recurrent separation-themed nightmares, stomach pain on school mornings, and repeated refusal to attend unless a caregiver remains nearby. The child fears that the caregiver will die while they are apart. This pattern may warrant assessment for Separation Anxiety Disorder because the separation focus, persistence, and impairment are all present; diagnosis still requires full clinical evaluation.
Example: possible adult disorder
An adult has several months of escalating fear that a spouse will be harmed whenever they are apart, repeatedly cancels work travel, cannot sleep when the spouse is away, and maintains employment only through constant checking and major schedule changes. Adult age does not exclude 6B05; the pattern warrants assessment of separation-focused fear, impairment, context, and alternative explanations.
Example: similar behavior, different focus
Another adult also avoids leaving home but does so because they fear having incapacitating symptoms in a place where escape or help would be difficult. The visible avoidance may resemble dependence on a companion, yet the focus of apprehension points toward agoraphobia rather than Separation Anxiety Disorder.
What the diagnosis does not mean
It does not mean that closeness, affection, loyalty, or a strong family bond is pathological. ICD-11 requires excessive fear or anxiety plus persistence and clinical significance.
It does not mean that every school-refusal episode is separation anxiety. School refusal is a behavior with multiple possible causes.
It does not mean that a panic attack equals Panic Disorder. Panic can occur within Separation Anxiety Disorder and can be coded as a qualifier when the relevant conditions are met.
It does not mean that an attachment-style score is a psychiatric diagnosis. Attachment anxiety and Separation Anxiety Disorder belong to different conceptual and clinical domains.
It does not mean that physical symptoms are “just anxiety.” Separation-related timing can be clinically informative, while medical causes still require appropriate consideration.
Why adult recognition changed the classification
The modern lifespan approach reflects a substantial evidence base accumulated before ICD-11 and DSM-5. Bögels and colleagues reviewed evidence showing adult Separation Anxiety Disorder to be clinically meaningful and not adequately captured by a childhood-onset requirement.
The World Mental Health Survey analysis by Silove and colleagues further demonstrated adult-onset cases in a large multinational sample. Those data used an expanded DSM-IV framework and therefore should be interpreted historically rather than as direct prevalence estimates under the final ICD-11 requirements.
The later ICD-11 field study by Rebello and colleagues provided a particularly relevant classification result: clinicians were significantly more accurate with adult Separation Anxiety Disorder cases using ICD-11 than ICD-10 guidelines.
Evidence strength and limitations
Established evidence supports Separation Anxiety Disorder as a clinically recognized anxiety or fear-related disorder across the lifespan in ICD-11, code 6B05, with separation from attachment figures as the defining focus, persistence over an extended period, and clinically significant impact.
Established classification evidence also supports removal of the childhood-onset restriction and the use of a lifespan framework. International ICD-11 field studies support the clinical utility and reliability of the broader diagnostic system.
The ICD-11 reliability field study found moderate to almost-perfect interdiagnostician reliability across the high-burden disorders examined overall, supporting the global implementation framework. It was not designed to prove a biological boundary for Separation Anxiety Disorder.
Prevalence estimates and many adult clinical studies come from DSM-based or pre-final-ICD-11 instruments. They inform the historical and developmental evidence base but should not be presented as if they were direct epidemiologic estimates under the final 2024 ICD-11 CDDR.
Treatment research specific to adult Separation Anxiety Disorder remains less extensive than the evidence base for several other anxiety disorders. This page therefore keeps treatment discussion limited and does not transfer efficacy claims from GAD, panic disorder, social anxiety disorder, or specific phobia automatically to 6B05.
Does diagnosis determine treatment?
Diagnosis helps organize a treatment formulation, but it does not select one intervention automatically. Age, developmental context, family or relationship dynamics, comorbidity, severity, risk, access to care, and patient preferences all matter.
Psychological treatment often addresses avoidance, feared separation, reassurance patterns, and age-appropriate autonomy, but specific intervention choices should be based on the evidence relevant to the person's age group and presentation. Medication decisions require individualized medical assessment and should not be inferred from a diagnostic article.
The immediate diagnostic task is narrower: establish whether 6B05 fits the current clinical pattern and whether another explanation is better.
Frequently asked questions
What is the ICD-11 code for Separation Anxiety Disorder?
The code is 6B05. The WHO ICD-11 classifies it within Anxiety or fear-related disorders.
Can adults be diagnosed with Separation Anxiety Disorder in ICD-11?
Yes. ICD-11 uses a lifespan approach and does not require onset during childhood. In adults, the attachment focus commonly involves a spouse or romantic partner or the person's children.
How long do symptoms need to last?
ICD-11 requires a persistent, non-transient pattern over an extended period and gives at least several months as an example. It does not use the DSM-5-TR age-specific duration wording.
Does ICD-11 require three symptoms?
No fixed “three symptoms” count is used in the ICD-11 CDDR essential-feature formulation. ICD-11 describes the required clinical pattern and gives manifestations as examples.
Is school refusal the same as Separation Anxiety Disorder?
No. School refusal is a behavior with many possible causes. Separation Anxiety Disorder is considered when fear of separation from an attachment figure is the central focus and the full ICD-11 requirements are met.
Can Separation Anxiety Disorder cause stomachaches or headaches?
Separation-related nausea, vomiting, stomach pain, and headache are listed by ICD-11 as possible manifestations. They are not specific to the disorder, and medically concerning symptoms should be assessed medically rather than assumed to be anxiety.
Can panic attacks occur with Separation Anxiety Disorder?
Yes. ICD-11 allows a panic-attack qualifier for 6B05 when panic attacks occur in association with Separation Anxiety Disorder without a co-occurring Panic Disorder diagnosis.
What is the difference between Separation Anxiety Disorder and attachment anxiety?
Separation Anxiety Disorder is a formal ICD-11 clinical diagnosis with requirements for a persistent, excessive, clinically significant separation-focused pattern. Attachment anxiety is a dimensional construct used in attachment and relationship research; it is not the same diagnosis.
Can a questionnaire diagnose 6B05?
No. Questionnaires can measure symptoms or flag a need for assessment. Formal diagnosis requires clinical evaluation of the full pattern, duration, developmental context, impairment, and differential diagnosis.
Is ICD-11 the same as DSM-5-TR for Separation Anxiety Disorder?
The systems are broadly aligned on the lifespan concept but differ in operational detail, including symptom-count and duration wording. See DSM-5-TR vs ICD-11 Anxiety Disorders: Key Classification Differences for the broader classification comparison.
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References
American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR). American Psychiatric Association Publishing. https://doi.org/10.1176/appi.books.9780890425787
Baldwin, D. S., Gordon, R., Abelli, M., & Pini, S. (2016). The separation of adult separation anxiety disorder. CNS Spectrums, 21(4), 289–294. https://doi.org/10.1017/S1092852916000080
Bögels, S. M., Knappe, S., & Clark, L. A. (2013). Adult separation anxiety disorder in DSM-5. Clinical Psychology Review, 33(5), 663–674. https://doi.org/10.1016/j.cpr.2013.03.006
Domschke, K., & Zwanzger, P. (2025). Taxonomy of anxiety disorders—a comparison of ICD-10 and ICD-11. Der Nervenarzt. https://doi.org/10.1007/s00115-025-01842-6
First, M. B., et al. (2021). An organization- and category-level comparison of diagnostic requirements for mental disorders in ICD-11 and DSM-5. World Psychiatry, 20(1), 34–51. https://doi.org/10.1002/wps.20825
Kogan, C. S., Stein, D. J., Maj, M., First, M. B., Emmelkamp, P. M. G., & Reed, G. M. (2016). The classification of anxiety and fear-related disorders in the ICD-11. Depression and Anxiety, 33(12), 1141–1154. https://doi.org/10.1002/da.22530
Manicavasagar, V., Silove, D., Wagner, R., & Drobny, J. (2003). A self-report questionnaire for measuring separation anxiety in adulthood. Comprehensive Psychiatry, 44(2), 146–153. https://doi.org/10.1053/comp.2003.50024
Rebello, T. J., et al. (2020). Anxiety and fear-related disorders in the ICD-11: Results from a global case-controlled field study. Archives of Medical Research, 50(8), 490–501. https://doi.org/10.1016/j.arcmed.2019.12.012
Reed, G. M., et al. (2018). Clinical utility of ICD-11 diagnostic guidelines for high-burden mental disorders: Results from mental health settings in 13 countries. World Psychiatry, 17(3), 306–315. https://doi.org/10.1002/wps.20581
Reed, G. M., et al. (2018). The ICD-11 developmental field study of reliability of diagnoses of high-burden mental disorders: Results among adult patients in mental health settings of 13 countries. World Psychiatry, 17(2), 174–186. https://doi.org/10.1002/wps.20524
Silove, D., et al. (2015). Pediatric-onset and adult-onset separation anxiety disorder across countries in the World Mental Health Survey. American Journal of Psychiatry, 172(7), 647–656. https://doi.org/10.1176/appi.ajp.2015.14091185
World Health Organization. (2024). Clinical descriptions and diagnostic requirements for ICD-11 mental, behavioural and neurodevelopmental disorders. https://www.who.int/publications/i/item/9789240077263