As noted by Altman, McGoey & Sommer, it is important to observe the child, "in multiple contexts, on numerous occasions, and in their everyday environments (home, daycare, preschool)". It is beneficial to view parent and child interactions and behaviors that may contribute to SAD.

Dyadic Parent-Child Interaction Coding System and recently the Dyadic Parent-Child Interaction Coding System II (DPICS II) are methods used when observing parents and children interactions.

Separation Anxiety Daily Diaries (SADD) have also been used to “assess anxious behaviors along with their antecedents and consequences and may be particularly suited to SAD given its specific focus on parent–child separation” (Silverman & Ollendick, 2005). The diaries are carefully evaluated for validity.

This form of assessment should not be the sole basis of a SAD diagnosis. It is also important to verify that the child who is reporting on their experiences has the cognitive and communication skills appropriate to accurately comprehend and respond to these measurements.

An example of a self-report tool that has been tested is: The Separation Anxiety Assessment Scale for Children (SAAS-C). The scale contains 34 items and is divided into six dimensions. The dimensions in order are: Abandonment, Fear of Being Alone, Fear of Physical Illness, Worry about Calamitous Events, Frequency of Calamitous Events, and Safety Signal Index. The first five dimensions have a total of five items while the last one contains nine items. The scale goes beyond assessing symptoms; it focuses on individual cases and treatment planning.

Dogs suffering from separation anxiety are often "owner addicts". Setting boundaries will boost a dog's confidence and prepare it to be on its own.

Various techniques have been suggested for helping dogs cope with separation anxiety:

- Leaving and returning home quietly, without fuss

- Providing plenty of exercise, play, and fun

- Practicing leaving to adjust the dog to your departure

- Feeding the dog before you leave

- Leaving the radio/TV on

- Medicating the dog

As of 2012, a San Diego cable channel is offering DOGTV, a cable-based television channel especially for dogs whose owners are away. The programming, created with the help of dog behavior specialists, is color-adjusted to appeal to dogs, and features 3–6 minute segments designed to relax, to stimulate, and to expose the dog to scenes of everyday life such as doorbells or riding in a vehicle. The channel's proponents have indicated positive reviews from a humane society shelter in Escondido, California. The "doggie resort" hosts of the opening party for Dog TV in San Diego reported that some of their dogs seem to enjoy watching the animated series "SpongeBob SquarePants". The show's creators anticipate that dogs will watch Dog TV intermittently, throughout the day, rather than remaining glued to the set.

Another technology based solution for calming separation anxious dogs is a software named Digital Dogsitter.

The user first records his or her voice to the software. When the dog is alone, the software listens to the dog and analyzes the incoming audio through the computer's microphone. Whenever the dog barks or howls, software plays the owner's voice to the dog, and the dog becomes calm.

The most common adverse effects related to fluoxetine treatment were decreased appetite, experienced by 23% of the dogs in the study, and lethargy, experienced by 39% of the dogs in the study. Some canines actually experienced worsening anxiety and aggressive behavior.

In the study with clomipramine, 9 dogs underwent withdrawal after discontinuing treatment. 5 of those dogs were successful in overcoming the withdrawal, while 4 dogs relapsed. With regards to these results it is important to note that these sample sizes were relatively small. However, these studies have given us a look at one of the many variables regarding psychoactive drug withdrawal.

With regards to benzodiazepine treatment, it has been found that canines can develop dependence to these types of medications and go through a similar withdrawal process as humans. For example, their seizure threshold is lowered and anxiety relapse can occur after stopping benzodiazepine treatment. Similarly to treatment of human anxiety disorders, benzodiazepines are a last resort treatment, due to their addiction potential.

The diagnosis of an anxiety disorder requires first ruling out an underlying medical cause. Diseases that may present similar to an anxiety disorder, including certain endocrine diseases (hypo- and hyperthyroidism, hyperprolactinemia), metabolic disorders (diabetes), deficiency states (low levels of vitamin D, B2, B12, folic acid), gastrointestinal diseases (celiac disease, non-celiac gluten sensitivity, inflammatory bowel disease), heart diseases, blood diseases (anemia), and brain degenerative diseases (Parkinson's disease, dementia, multiple sclerosis, Huntington's disease).

Also, several drugs can cause or worsen anxiety, whether in intoxication, withdrawal, or from chronic use. These include alcohol, tobacco, cannabis, sedatives (including prescription benzodiazepines), opioids (including prescription pain killers and illicit drugs like heroin), stimulants (such as caffeine, cocaine and amphetamines), hallucinogens, and inhalants.

Certain children who are particularly attached to their mother or other family figure due to separation anxiety and/or attachment theory often suffer the onset early, in pre-school, crèche or before school starts.

School phobia is diagnosed primarily through questionnaires and interviews with doctors. Other methods like observation have not proven to be as useful. This is partly because (school) anxiety is an internal phenomenon. An example of a modern multidimensional questionnaire is the "Differential Power Anxiety Inventory 'approach, with twelve scales to diagnose four different areas: anxiety-inducing conditions, manifestations, coping strategies and stabilization forms."

- Cognitive and lifestyle exploration

- 'School Phobia Test' (SAT)

- 'Anxiety questionnaire for students', (AFS)

The DSM-IV-TR diagnostic criteria for panic disorder require unexpected, recurrent panic attacks, followed in at least one instance by at least a month of a significant and related behavior change, a persistent concern of more attacks, or a worry about the attack's consequences. There are two types, one with and one without agoraphobia. Diagnosis is excluded by attacks due to a drug or medical condition, or by panic attacks that are better accounted for by other mental disorders.

The diagnostic criteria:

The essential feature is recurrent attacks of severe anxiety (panic), which are not restricted to any particular situation or set of circumstances and are therefore unpredictable.

The dominant symptoms include:

- sudden onset of palpitations

- chest pain

- choking sensations

- dizziness

- feelings of unreality (depersonalization or derealization)

- secondary fear of dying, losing control, or going mad

Panic disorder should not be given as the main diagnosis if the person has a depressive disorder at the time the attacks start; in these circumstances, the panic attacks are probably secondary to depression.

The Panic Disorder Severity Scale (PDSS) is a questionnaire for measuring the severity of panic disorder.

Anxiety disorders are often severe chronic conditions, which can be present from an early age or begin suddenly after a triggering event. They are prone to flare up at times of high stress and are frequently accompanied by physiological symptoms such as headache, sweating, muscle spasms, tachycardia, palpitations, and hypertension, which in some cases lead to fatigue.

In casual discourse the words "anxiety" and "fear" are often used interchangeably; in clinical usage, they have distinct meanings: "anxiety" is defined as an unpleasant emotional state for which the cause is either not readily identified or perceived to be uncontrollable or unavoidable, whereas "fear" is an emotional and physiological response to a recognized external threat. The term "anxiety disorder" includes fears (phobias) as well as anxieties.

The diagnosis of anxiety disorders is difficult because there are no objective biomarkers, it is based on symptoms, which typically need to be present at least six months, be more than would be expected for the situation, and decrease functioning. Several generic anxiety questionnaires can be used to detect anxiety symptoms, such as the State-Trait Anxiety Inventory (STAI), the Generalized Anxiety Disorder 7 (GAD-7), the Beck Anxiety Inventory (BAI), the Zung Self-Rating Anxiety Scale, and the Taylor Manifest Anxiety Scale. Other questionnaires combine anxiety and depression measurement, such as the Hamilton Anxiety Rating Scale, the Hospital Anxiety and Depression Scale (HADS), the Patient Health Questionnaire (PHQ), and the Patient-Reported Outcomes Measurement Information System (PROMIS). Examples of specific anxiety questionnaires include the Liebowitz Social Anxiety Scale (LSAS), the Social Interaction Anxiety Scale (SIAS), the Social Phobia Inventory (SPIN), the Social Phobia Scale (SPS), and the Social Anxiety Questionnaire (SAQ-A30).

Anxiety disorders often occur along with other mental disorders, in particular depression, which may occur in as many as 60% of people with anxiety disorders. The fact that there is considerable overlap between symptoms of anxiety and depression, and that the same environmental triggers can provoke symptoms in either condition, may help to explain this high rate of comorbidity.

Studies have also indicated that anxiety disorders are more likely among those with family history of anxiety disorders, especially certain types.

Sexual dysfunction often accompanies anxiety disorders, although it is difficult to determine whether anxiety causes the sexual dysfunction or whether they arise from a common cause. The most common manifestations in individuals with anxiety disorder are avoidance of intercourse, premature ejaculation or erectile dysfunction among men and pain during intercourse among women. Sexual dysfunction is particularly common among people affected by panic disorder (who may fear that a panic attack will occur during sexual arousal) and posttraumatic stress disorder.

Panic disorder typically begins during early adulthood; roughly half of all people who have panic disorder develop the condition before age 24, especially those subjected to traumatic experiences. However, some sources say that the majority of young people affected for the first time are between the ages of 25 and 30. Women are twice as likely as men to develop panic disorder and it occurs more often in people with above average intelligence.

Panic disorder can continue for months or years, depending on how and when treatment is sought. If left untreated, it may worsen to the point where one's life is seriously affected by panic attacks and by attempts to avoid or conceal the condition. In fact, many people have had problems with personal relationships or employment while struggling to cope with panic disorder. Some people with panic disorder may conceal their condition because of the stigma of mental illness. In some individuals, symptoms may occur frequently for a period of months or years, then many years may pass without symptoms. In some cases, the symptoms persist at the same level indefinitely. There is also some evidence that many individuals (especially those who develop symptoms at an early age) may experience symptom cessation later in life (e.g. past age 50).

In 2000, the World Health Organization found prevalence and incidence rates for panic disorder to be very similar across the globe. Age-standardized prevalence per 100,000 ranged from 309 in Africa to 330 in East Asia for men and from 613 in Africa to 649 in North America, Oceania, and Europe for women.

According to the fourth revision of the "Diagnostic and Statistical Manual of Mental Disorders", phobias can be classified under the following general categories:

- Animal type – Fear of dogs, cats, rats and/or mice, pigs, cows, birds, spiders, or snakes.

- Natural environment type – Fear of water (aquaphobia), heights (acrophobia), lightning and thunderstorms (astraphobia), or aging (gerascophobia).

- Situational type – Fear of small confined spaces (claustrophobia), or the dark (nyctophobia).

- Blood/injection/injury type – this includes fear of medical procedures, including needles and injections (trypanophobia), fear of blood (hemophobia) and fear of getting injured.

- Other – children's fears of loud sounds or costumed characters.

Most people who present to mental health specialists develop agoraphobia after the onset of panic disorder. Agoraphobia is best understood as an adverse behavioral outcome of repeated panic attacks and subsequent anxiety and preoccupation with these attacks that leads to an avoidance of situations where a panic attack could occur. Early treatment of panic disorder can often prevent agoraphobia. Agoraphobia is typically determined when symptoms are worse than panic disorder, but also do not meet the criteria for other anxiety disorders such as depression. In rare cases where agoraphobics do not meet the criteria used to diagnose panic disorder, the formal diagnosis of agoraphobia without history of panic disorder is used (primary agoraphobia).

Approximately 1 to 5% of school-aged children have school refusal, though it is most common in 5- and 6-year olds and in 10- and 11-year olds, it occurs more frequently during major changes in a child’s life, such as entrance to kindergarten, changing from elementary to middle school, or changing from middle to high school. The problem may start following vacations, school holidays, summer vacation, or brief illness, after the child has been home for some time, and usually ends prior to vacations, school holidays, or summer vacation, before the child will be out of school for some time. School refusal can also occur after a stressful event, such as moving to a new house, or the death of a pet or relative.

The rate is similar within both genders, and although it is significantly more prevalent in some urban areas, there are no known socioeconomic differences.

Main features of diagnostic criteria for specific phobia in the DSM-IV-TR:

- Marked and persistent fear that is excessive or unreasonable, cued by the presence or anticipation of a specific object or situation (e.g., flying, heights, animals, receiving an injection, seeing blood).

- Exposure to the phobic stimulus almost invariably provokes an immediate anxiety response, which may take the form of a situationally bound or situationally predisposed panic attack. In children, the anxiety may be expressed by crying, tantrums, freezing, or clinging.

- The person recognizes that the fear is excessive or unreasonable. In children, this feature may be absent.

- The phobic situation(s) is avoided or else is endured with intense anxiety or distress.

Specific Phobia – DSM 5 Criteria

- Fear or anxiety about a specific object or situation (In children fear/anxiety can be expressed by crying, tantrums, freezing, or clinging)

- The phobic object or situation almost always provokes immediate fear or anxiety

- The phobic object or situation is avoided or endured with intense fear or anxiety

- The fear or anxiety is out of proportion to the actual danger posed by the specific object or situation and to the sociocultural context

- The fear, anxiety, or avoidance is persistent, typically lasting for 6 months or more

- The fear, anxiety, or avoidance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning

- The disturbance is not better explained by symptoms of another mental disorder, including fear, anxiety, and avoidance of situations associated with panic-like symptoms or other incapacitating symptoms; objects or situations related to obsessions; reminders of traumatic events; separation from home or attachment figures; or social situations

The ICD-10 defines hypochondriasis as follows:

The DSM-IV defines hypochondriasis according to the following criteria:

A. Preoccupation with fears of having, or the idea that one has, a serious disease based on the person's misinterpretation of bodily symptoms.

B. The preoccupation persists despite appropriate medical evaluation and reassurance.

C. The belief in Criterion A is not of delusional intensity (as in Delusional Disorder, Somatic Type) and is not restricted to a circumscribed concern about appearance (as in Body Dysmorphic Disorder).

D. The preoccupation causes clinically significant distress or impairment in

social, occupational, or other important areas of functioning.

E. The duration of the disturbance is at least 6 months.

F. The preoccupation is not better accounted for by Generalized Anxiety Disorder, Obsessive-Compulsive Disorder, Panic Disorder, a Major Depressive Episode, Separation Anxiety, or another Somatoform Disorder.

The newly published DSM-5 replaces the diagnosis of hypochondriasis with "illness anxiety disorder".

The basis of the diagnosis is the presence of a precipitating stressor and a clinical evaluation of the possibility of symptom resolution on removal of the stressor due to the limitations in the criteria for diagnosing AD. In addition, the diagnosis of AD is less clear when patients are exposed to stressors long-term, because this type of exposure is associated with AD and major depressive disorder (MDD) and generalized anxiety disorder (GAD).

Some signs and criteria used to establish a diagnosis are important. First, the symptoms must clearly follow a stressor. The symptoms should be more severe than would be expected. There should not appear to be other underlying disorders. The symptoms that are present are not part of a normal grieving for the death of family member or other loved one.

Adjustment disorders have the ability to be self-limiting. Within five years of when they are originally diagnosed, approximately 20%–50% of the sufferers go on to be diagnosed with psychiatric disorders that are more serious.

Most research indicates that cognitive behavioral therapy (CBT) is an effective treatment for hypochondriasis. Much of this research is limited by methodological issues. A small amount of evidence suggests that selective serotonin reuptake inhibitors can also reduce symptoms, but further research is needed.

According to Child and Adolescent Mental Health, approximately 5 percent of children suffer from specific phobias and 15 percent seek treatment for anxiety-related problems. In recent years the number of children with clinically diagnosed phobias has gradually increased. Researchers are finding that the majority of these diagnoses come anxiety related phobias or society phobias.

Specific phobias are more prevalent in girls than in boys. Likewise, specific phobias are also more prevalent in older children than younger.

International Statistical Classification of Diseases and Related Health Problems, mostly known as "ICD", assigns codes to classify diseases, symptoms, complaints, social behaviors, injuries, and such medical-related findings.

ICD 10 classifies adjustment disorders under F40-F48 and under neurotic, stress-related and somatoform disorders.

Though some fears are inborn, the majority are learned. Phobias develop through negative experiences and through observation. One way children begin to develop fears is by witnessing or hearing about dangers. Ollendick proposes while some phobias may originate from a single traumatizing experience, others may be caused by simpler, or less dramatic, origins such as observing another child’s phobic reaction or through the exposure to media that introduces phobias.

- 2% of parents linked their child’s phobia to a [direct conditioning episode]

- 26% of parents linked their child’s phobia to a [vicarious conditioning episodes]

- 56% of parents linked their child’s phobia to their child’s very first contact with water

- 16% of parents could not directly link their child’s phobia

In addition to asking about the origins of a child’s fear, the questionnaire asked if parents believed that “information associated with adverse consequences was the most influential factor in the development of their child’s phobia.” The results were as followed:

- 0% of parents though it was the most influential factor

- 14% of parents though it was somewhat influential

- 86% of parents though it had little to no influence

Agoraphobia occurs about twice as commonly among women as it does in men. The gender difference may be attributable to several factors: sociocultural traditions that encourage, or permit, the greater expression of avoidance coping strategies by women (including dependent and helpless behaviors), women perhaps being more likely to seek help and therefore be diagnosed, and men being more likely to abuse alcohol in reaction to anxiety and be diagnosed as an alcoholic. Research has not yet produced a single clear explanation for the gender difference in agoraphobia.

Panic disorder with or without agoraphobia affects roughly 5.1% of Americans, and about 1/3 of this population with panic disorder have comorbid agoraphobia. It is uncommon to have agoraphobia without panic attacks, with only 0.17% of people with agorophobia not presenting panic disorders as well.

The most common methods for the treatment of specific phobias are systematic desensitization and in vivo or exposure therapy.

Although most commonly done with the help of a therapist in a professional setting, exposure to dogs is also possible as a self-help treatment. First, the patient is advised to enlist the help of an assistant who can help set-up the exposure environment, assist in handling the dog during sessions, and demonstrate modeling behaviors. This should also be someone whom the patient trusts and who has no fear of dogs. Then, the patient compiles a hierarchy of fear provoking situations based on their rating of each situation. For example, on a scale from 0 to 100, a patient may feel that looking at photos of dogs may cause a fear response of only 50, however, petting a dog's head may cause of fear response of 100. This list of situations looking at dog photos) to most fearful (petting a dog's head) and the assistant helps the patient to identify common elements that contribute to the fear (i.e., size of the dog, color, how it moves, noise, whether or not it is restrained, etc.). Next, the assistant helps the patient recreate the least fearful situation in a safe, controlled environment, continuing until the patient has had an opportunity to allow the fear to subside thus reinforcing the realization that the fear is unfounded. Once a situation has been mastered, the next fearful situation is recreated and the process is repeated until all the situations in the hierarchy have been experienced.

Sample videos showing humans and dogs interacting without either exhibiting significant fear are available.

There are a variety of mainstream prevention programs and treatment approaches for attachment disorder, attachment problems and moods or behaviors considered to be potential problems within the context of attachment theory. All such approaches for infants and younger children concentrate on increasing the responsiveness and sensitivity of the caregiver, or if that is not possible, changing the caregiver. Such approaches include 'Watch, wait and wonder,' manipulation of sensitive responsiveness, modified 'Interaction Guidance,'. 'Preschool Parent Psychotherapy,'. Circle of Security', Attachment and Biobehavioral Catch-up (ABC), the New Orleans Intervention, and Parent-Child psychotherapy. Other known treatment methods include Developmental, Individual-difference, Relationship-based therapy (DIR) (also referred to as "Floor Time") by Stanley Greenspan, although DIR is primarily directed to treatment of pervasive developmental disorders Some of these approaches, such as that suggested by Dozier, consider the attachment status of the adult caregiver to play an important role in the development of the emotional connection between adult and child. This includes foster parents, as children with poor attachment experiences often do not elicit appropriate caregiver responses from their attachment behaviors despite 'normative' care.

Treatment for reactive attachment disorder for children usually involves a mix of therapy, counseling, and parenting education. These must be designed to make sure the child has a safe environment to live in and to develop positive interactions with caregivers and improves their relationships with their peers.

Medication can be used as a way to treat similar conditions, like depression, anxiety, or hyperactivity; however, there is no quick fix for treating reactive attachment disorder. A pediatrician may recommend a treatment plan. For example, a mix of family therapy, individual psychological counseling, play therapy, special education services and parenting skills classes.

Some scholars believe that codependency is not a negative trait, and does not need to be treated, as it is more likely a healthy personality trait taken to excess. Codependency in nonclinical populations has some links with favourable characteristics of family functioning.

Stan Katz states that codependence is over-diagnosed, and that many people who could be helped with shorter-term treatments instead become dependent on long-term self-help programs. The language of, symptoms of, and treatment for codependence derive from the medical model suggesting a disease process underlies the behavior. However, there is no evidence that codependence is caused by a disease process.

In their book, “Attached.”, Dr. Amir Levine and Rachel S. F. Heller, address what they call the “codependency myth” by asserting that attachment theory is a more scientific and helpful model for understanding and dealing with attachment in adults.

Fear of the dark is a common fear or phobia among children and, to a varying degree, adults.