Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Major Depressive Disorder

Related Terms

  • Clinical Depression
  • Depressive Psychosis
  • Endogenous Depression
  • Major Depressive Disorder
  • Psychotic Depression
  • Unipolar Depression

Differential Diagnosis


  • Clinical Psychologist
  • Psychiatrist

Comorbid Conditions

Factors Influencing Duration

Length of disability may be influenced by the severity of the illness, the presence of complicating factors such as substance abuse or suicide attempts, response to therapy, and job requirements. Only in the most severe and unusual cases should major depression result in permanent disability.

Substance abuse will complicate treatment and may significantly delay returning to work. Suicide attempts that lead to hospitalization will also be associated with longer periods of disability.

Medical Codes

296.20 - Major Depressive Disorder, Single Episode; Unspecified
296.21 - Major Depressive Disorder, Single Episode; Mild
296.22 - Major Depressive Disorder, Single Episode; Moderate
296.23 - Major Depressive Disorder, Single Episode; Severe, without Mention of Psychotic Behavior
296.24 - Major Depressive Disorder, Single Episode; Severe, Specified as with Psychotic Behavior
296.25 - Major Depressive Disorder, Single Episode; in Partial or Unspecified Remission
296.26 - Major Depressive Disorder, Single Episode; in Full Remission
296.30 - Major Depressive Disorder, Recurrent Episode; Unspecified
296.31 - Major Depressive Disorder, Recurrent Episode; Mild
296.32 - Major Depressive Disorder, Recurrent Episode; Moderate
296.33 - Major Depressive Disorder, Recurrent Episode; Severe, without Mention of Psychotic Behavior
296.34 - Major Depressive Disorder, Recurrent Episode; Severe, Specified as with Psychotic Behavior
296.35 - Major Depressive Disorder, Recurrent Episode; in Partial or Unspecified Remission
296.36 - Major Depressive Disorder, Recurrent Episode; in Full Remission
311 - Depressive Disorder, Not Elsewhere Classified


Major depressive disorder (also known as major depression) is a mood disorder characterized by the presence of sad, empty, or irritable mood, with somatic and cognitive changes that negatively affect the individual's capacity to function. It is one of several types of depressive disorder. Major depression is responsible for more physical and social dysfunction than many chronic medical conditions. Individuals with major depression find it difficult to cope with normal life activities or to feel or enjoy the pleasures of life.

Everyone experiences depressed moods as a result of a change, either in the form of a setback or a loss. The sadness and depressed feelings that accompany the changes and losses of life are usually appropriate, necessary, and transient and can present an opportunity for personal growth. However, depression that persists and results in serious dysfunction in daily life may indicate a depressive disorder that may need to be treated as a medical problem. The severity, duration, and presence of other symptoms are factors that distinguish normal sadness from a depressive disorder.

Major depression, known as major depressive disorder in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, 5th Edition), is a mood disorder distinguished by the occurrence of one or more major depressive episodes. A major depressive episode is diagnosed when an individual experiences five or more of the following nine symptoms for at least two consecutive weeks (at least one of the symptoms is depressed mood or loss of interest or pleasure [anhedonia]): depressed mood; marked reduction of interest or pleasure in all, or almost all, activities most of the day, nearly every day; changes in appetite that result in weight losses or gains unrelated to dieting; insomnia or oversleeping nearly every day; psychomotor agitation or retardation nearly every day; loss of energy or increased fatigue; feelings of worthlessness or inappropriate guilt; difficulty thinking, concentrating, or making decisions; and recurrent thoughts of death or suicide, or attempts at suicide. The symptoms produce significant distress or impairment in social, occupational, or other areas of functioning, and the episode is not accounted for by the physiological effects of a substance or by another medical condition. The occurrence of one major depressive episode typically leads to the diagnosis of major depressive disorder except under a few circumstances, such as having had a manic or hypomanic episode in the past. A cause or trigger for major depression may not be identified in all individuals. However, genetic predisposition and/or disturbances in levels of the neurotransmitters serotonin, dopamine, and norepinephrine are believed to be the underlying metabolic abnormalities in most cases.

Grief is a psychological and emotional reaction to a significant loss, including the loss of a spouse or loved one; early bereavement-related responses may be disbelief, low mood, insomnia, and loss of appetite, accompanied by disrupted functioning. Bereavement may induce great suffering, but it does not typically induce an episode of major depressive disorder; bereavement-related depression tends to occur in individuals prone to depressive disorders.

A depressive episode is diagnosed only if the symptoms described above are not associated with any other psychiatric conditions (such as bipolar disorder) or medical conditions (such as neurological or hormonal problems, cancer, or an individual's state of health after a stroke or a heart attack [myocardial infarction]). In the latter case, the diagnosis is depressive disorder due to another medical condition, and the medical condition must be particularly specified. To be diagnostic for major depression, symptoms must not be due to side effects of medications or substance abuse.

The DSM-5 adds several specifiers to a diagnosis of major depressive disorder based, for example, on whether the individual has experienced a single depressive episode or recurrent depressive episodes; severity is rated along a continuum of mild, moderate, severe, and severe with psychotic features. The latter is sometimes known as depressive psychosis. Partial and full remissions are additional specifiers for major depressive episodes. At least 2 consecutive months in-between episodes of major depression are necessary to qualify as a new episode of depression.

Incidence and Prevalence: Depression of all types affects 19% of the population at some point in life. In the US, the lifetime risk is 23% for women and 15% for men (Kessler). An international study involving 17 researchers and 38,000 individuals from 10 countries reported that the lifetime risk of depression ranged from 1.5% in Taiwan to 19% in Lebanon. Risks in other countries, in ascending order, were 2.9% in Korea, 4.3% in Puerto Rico, 5.2% in the US, 9.2% in Germany, 9.6% in Canada, 11.6% in New Zealand, and 16.4% in France (Weissman). The 30-day prevalence and lifetime prevalence of major depression were shown to be 0.2% and 5% in men 65 and older, and 1.5% and 13% in women 65 and older, respectively (Kessler).

Source: Medical Disability Advisor

Causation and Known Risk Factors

According to the DSM-5, anyone of any age, race, class, or gender can experience depression. Depression and chronic medical conditions have a reciprocal relationship. Depression is associated with increased rates of chronic health conditions, and chronic health conditions may trigger depression (Kravitz). Major risk factors are female gender, age, family history, bereavement (see above), history of childhood sexual abuse, and a history of previous depression (Kessler; Kravitz; Patten; Klein). Women suffer from the disorder at least twice as often as men in societies around the world. The peak age of onset is typically in early adulthood (Kessler). Individuals who have a family history of major depression have a greater risk (about 2 times) of developing this disorder (Klein).

Source: Medical Disability Advisor


History: The individual may report sadness, anxiety, fatigue, loss of appetite, and insomnia, among other symptoms. A thorough history includes a review of current and previous symptoms, previous depressive episodes, recent disturbing thoughts or events, and psychological problems that could predispose to depression; an evaluation of mood, memory, and changes in relationships; a corroborative history from friends, family members, or employers; and any family history of depression or suicides. A careful, nonjudgmental inventory of substance abuse is made, as well as a review of all current and prior medications, especially antihypertensive agents (such as calcium channel blockers and beta blockers), analgesics, and certain migraine medicines, for which depression is a side effect. Because certain clinical conditions and diseases have been associated with depression, a thorough history includes an account of neurologic disorders (post-stroke disorders, Parkinson's disease, Alzheimer's disease, multiple sclerosis, epilepsy, encephalitis, brain tumors), endocrine disorders (diabetes mellitus, hypothyroidism, hyperthyroidism, hyperparathyroidism), and other disorders (coronary artery disease; post-heart attack conditions; cancer; autoimmune diseases such as fibromyalgia, rheumatoid arthritis, and lupus; and chronic fatigue syndrome). Conversely, individuals with major depression may seek medical care for headache, abdominal pain, body aches, low energy, malaise, or problems with sexual function.

It is also important to consider the possibility, particularly in medico-legal contexts, that the history offered by the individual may not reflect the underlying facts. In cases in which there is such a consideration, careful inspection of the record for other signs of symptom exaggeration, such as the presence of positive Waddell signs, a history that varies widely from one examiner to another, or erratic performance on a functional capacity evaluation, can be tip-offs. Psychological tests that contain internal validity scales and symptom validity tests can be useful in separating individuals presenting with a depressive problem from individuals merely representing themselves as presenting with a depressive problem.

Physical exam: Complete physical examination and medical workup are indicated to rule out underlying medical conditions (e.g., neurological, endocrine, or vascular conditions) that may disturb or deplete levels of serotonin and norepinephrine. Illnesses that are frequently associated with depression include hypo- and hyperthyroidism and other glandular disturbances, cancer, and post-stroke and post-heart attack conditions.

Tests: Major depression is diagnosed primarily through observation and history. However, routine laboratory tests (e.g., complete blood count [CBC], electrolytes, and serum calcium) may be done to evaluate metabolic disturbances and vascular disorders, Thyroid-stimulating hormone (TSH) may be measured to identify hypo- or hyperthyroidism, and more specialized endocrine tests may be helpful in establishing the diagnosis. Electroencephalography (EEG) may be performed to exclude epilepsy, and computed tomography (CT) imaging or brain scans may also be requested to identify or rule out relatively rare causes such as brain tumor or a clinically silent stroke. Psychological tests such as the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and the Beck Depression Inventory (BDI) may be useful in establishing a baseline of reported symptoms and monitoring response to treatment. Specialized neurological testing may be recommended.

Source: Medical Disability Advisor


Treatment choice depends on the outcome of the evaluation (history, physical exam, and tests). Treatment usually consists of some form of psychotherapy, antidepressant medications, or a combination of the two. One or more antidepressant medications may be prescribed, such as selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), or monoamine oxidase inhibitors (MAOIs). These medications work by correcting imbalances in the levels of brain chemicals (the monoamine neurotransmitters serotonin, dopamine, and norepinephrine). About two-thirds of individuals treated will respond to one or more medications. Generally, these medications take full effect 3 to 6 weeks after treatment has begun. Psychiatrists usually recommend that individuals continue to take the medication for five or more months after symptoms have improved.

Psychotherapy, especially cognitive behavioral therapy, may be used alone for treatment of mild depression. Antidepressant medications in combination with psychotherapy are preferred treatments in the more severe forms of major depressive disorder. In addition to cognitive behavioral therapy, the different types of psychotherapy include psychodynamic psychotherapy, interpersonal therapy, and supportive psychotherapy. Research suggests that using a combination of antidepressants and talk therapy is more effective than either treatment alone for most individuals.

Treatment of depression consists of three phases. Acute treatment, lasting 6 to 12 weeks, is aimed at remission of symptoms. Continuation treatment, lasting 4 to 9 months, is aimed at preventing relapse; during this phase, medication is continued at full dosage, and psychotherapy may be initiated. Maintenance treatment is aimed at preventing new episodes (recurrence) in individuals with prior episodes. Both maintenance medication and maintenance psychotherapy can prevent relapse or delay the next episode.

Electroconvulsive therapy (ECT) is another treatment option that has been shown to be safe and effective in treating individuals of all ages who have not responded sufficiently to antidepressant medications and psychotherapy or whose depression is severe and prolonged. Although the precise mechanism of action of ECT is not understood, it is believed to work by increasing neurotransmitter levels in the brain, improving neurotransmission and elevating mood (Moore). Recently other forms of interventions such as transcranial magnetic stimulation have become available. Experimental treatments include the use of agents such as ketamine intravenously.

For individuals whose depressive episodes can be attributed to use of specific medications, changes in medication or changes in dosage may be required.

Psychiatric hospitalization is warranted when the individual neglects self-care or is at high risk of self-harm. Other forms of more intensive treatment, such as partial hospitalization and intensive outpatient care, may be considered for individuals who fail to recover in a reasonable period of time with more standard treatments.

Before treatment, individuals and their families should be educated about the diagnosis, likely outcome, treatment options, cost of treatment, and potential side effects and complications.

Source: Medical Disability Advisor


Most individuals with a major depressive disorder will get better, responding favorably to at least one antidepressant medication. Individuals may also benefit from psychotherapy. With time, recovery is usually complete, though the risk of relapse increases with each episode. More than half of all individuals with one episode of major depression will have another, while those individuals with a history of three previous episodes have a 90% likelihood of having a fourth. Because of this high relapse rate, it is recommended that individuals with a history of multiple depressive episodes receive medication for the rest of their lives.

Spontaneous recovery may take months, during which time the individual is at great risk of complications. According to the DSM-5, risk of recurrence becomes progressively lower with the passage of time. Risk of recurrence is higher in severe depression and in those who have already had recurrent episodes. Persistence of mild depressive symptoms during a period of remission portends a poorer prognosis.

Poor outcome is associated with inadequate treatment, severe initial symptoms (including psychosis), early age of onset, greater number of previous episodes, incomplete recovery after 1 year, pre-existing severe mental or medical disorder, and family dysfunction.

Source: Medical Disability Advisor


Substance abuse, especially alcohol, frequently complicates a diagnosis of depression, although in some cases it may be difficult to determine which problem is primary. Individuals with major depression frequently also have anxiety disorders, such as post-traumatic stress disorder (PTSD), obsessive-compulsive disorder, panic disorder, social phobia, and generalized anxiety disorder. Anxiety symptoms may require special treatment but frequently respond to antidepressant medications, reinforcing the view that the two disorders share common brain chemistry imbalances (NIMH).

In extremely severe cases of major depression, psychotic symptoms may be present, such as hearing voices (auditory hallucinations) or having false beliefs (delusions).

According to the DSM-5, the possibility of suicide is always present in those with major depression. Most successful suicides (2 out of 3) are not preceded by unsuccessful attempts (Rihmer). Past history of suicide attempts, male gender, being single, living alone, or having prominent feelings of hopelessness or borderline personality disorder increases the risk of suicide. Suicide attempts may paradoxically occur as the individual begins to respond to therapy because the extreme apathy sometimes seen in major depression before treatment may actually preclude committing suicide due to lack of motivation or energy.

Source: Medical Disability Advisor

Ability to Work (Return to Work Considerations)

Temporary work accommodations may include the avoidance of stressful situations. Some or all of the following may be necessary: (1) reducing or eliminating activities where the safety of self or others is contingent upon a constant and/or high level of alertness, such as driving motor vehicles, operating complex machinery, or handling dangerous chemicals; (2) introducing the individual to new or stressful situations gradually under individually appropriate supervision; (3) allowing some flexibility in scheduling to attend psychotherapy appointments (which normally should occur during the employee's personal time); (4) promoting planned, proactive management of identified problem areas; and (5) offering timely feedback on job performance issues. It will be helpful if accommodations are documented in a written plan designed to promote timely and safe transition back to full work productivity. Daytime work hours may be necessary for a period of time.

For more information refer to "Work Ability and Return to Work," pages 411–426.

Risk: There is no risk to individuals working with major depression or risk to the individual's coworkers unless substance abuse or suicidal ideation is present. Participation in work activities is usually beneficial.

Capacity: Capacity is dependent on the individual’s level of mental alertness and whether a comorbid anxiety disorder is present. Work tasks that are familiar, simple, and do not require intense concentration or multitasking may be appropriate.

Tolerance: Tolerance is dependent on the individual’s motivation. In most cases, involvement with work activities is beneficial to recovery.

Source: Medical Disability Advisor

Maximum Medical Improvement

270 days (varies if this is chronic or a single isolated event).

Source: Medical Disability Advisor

Failure to Recover

If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case.

Regarding diagnosis:

  • Was a thorough history obtained? Does individual have a history of prior depressive episodes? Does family have a history of depression or of suicides?
  • Was substance abuse identified or ruled out?
  • Does individual have a history of psychological problems? Does individual have any physical conditions such as neurologic disorders (stroke, Parkinson's disease, epilepsy), endocrine disorders (diabetes mellitus, hypothyroidism, or hyperparathyroidism), or other disorders (cancer, coronary artery disease)?
  • Were endocrine tests done?
  • Were neurological tests done?
  • Were specific psychological tests, including symptom validity tests, carried out? What did they show?
  • Were brain scans performed to rule out brain tumor or prior silent stroke?
  • Is the physician an expert in diagnosis and psychopharmacology?
  • Was diagnosis confirmed?
  • Is it possible that individual was misdiagnosed?
  • Would individual benefit from a second opinion?

Regarding treatment:

  • Since major depression can be the result of biochemical imbalances in the brain, is the physician adequately trained in psychopharmacology?
  • Do drug dosages need to be adjusted to achieve therapeutic benefit?
  • Is individual responding favorably to current medication(s)? Is a change of medication warranted at this time?
  • Was individual made aware of possible medication side effects and what to do if a side effect is experienced?
  • If individual is experiencing side effects from current medication, is individual comfortable with and diligent in reporting side effects to the physician? If not, does individual trust family member or caregiver to share this information with the physician?
  • Is psychotherapy being used as part of individual's treatment regimen?
  • Is individual learning to recognize and change behavior, thoughts, or relationships that cause or maintain depression? Is therapy helping individual to develop more healthful and rewarding habits?
  • Are underlying medical conditions that may complicate treatment or influence recovery being effectively addressed or treated?
  • If individual's depression is incapacitating, severe, and life-threatening, or if he or she cannot take or does not respond to antidepressant medications, is ECT being considered at this time?
  • Is individual seriously contemplating suicide? Has individual previously attempted it? Does the threat of self-harm or personal neglect put individual at risk?
  • Is individual frail because of weight loss or at risk for heart problems because of severe agitation?
  • Would individual benefit from hospitalization, partial hospitalization, or intensive outpatient care until self-care is possible?

Regarding prognosis:

  • If diagnosis and treatment are accurate, can individual comprehend and follow medication treatment regimen, including proper dosage, time to take medication, and how to increase dosage when ordered? If individual is not capable, is another responsible individual available to oversee treatment? If not, would individual benefit from hospitalization until self-care is possible?
  • Does individual have a good working rapport with his or her physician?
  • Does individual know how often to see physician, and is transportation available? Is individual diligent about keeping appointments?
  • Has physician informed individual about how to improve response to treatment and which activities to avoid to increase the likelihood of improvement? Is individual engaged in psychotherapy?
  • What other support is available to individual? Family? Friends? Church? Support group?
  • Is there any evidence to suggest that the condition is prolonged for the purpose of some sort of financial or other gain?

Source: Medical Disability Advisor



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Diagnostic and Statistical Manual of Mental Disorders (DSM-5). 5th ed. American Psychiatric Association, 2013.

Hensley, Paula, and Paula Clayton. "Bereavement-related Depression." Psychiatric Times 25 8 (2008): NA.

Karam, E. G. , et al. "Bereavement Related and Non-Bereavement Related Depressions: A Comparative Field Study." Journal of Affective Disorders 112 (2009): 102-110.

Kessler, R. C. , and E. J. Bromet. "The Epidemiology of Depression across Cultures." Annual Review of Public Health 34 (2013): 119-138.

Kessler, R. C. , et al. "Age Differences in Major Depression: Results from the National Comorbidity Survey Replication (Ncs-R)." Psychological Medicine 40 (2010): 225-237.

Kessler, R. C. , et al. "Development of Lifetime Comorbidity in the World Health Organization World Mental Health Surveys." Archives of General Psychiatry 68 (2011): 90-100.

Klein, D. N. , et al. "Predictors of First Lifetime Onset of Major Depressive Disorder in Young Adulthood." Journal of Abnormal Psychology 122 (2013): 1-6.

Kravitz, R. L. , and D. E. Ford. "Introduction: Chronic Medical Conditions and Depression--the View from Primary Care." American Journal of Medicine 121 (2008): S1-S7.

Moore, David P., and James W. Jefferson, eds. Handbook of Medical Psychiatry. 2nd ed. Philadelphia: Mosby Elsevier, 2008.

Patten, S. B. "Major Depression Epidemiology from a Diathesis-Stress Conceptualization." BMC Psychiatry 13 (2013): 19.

Rihmer, Z. "Suicide Risk in Mood Disorders." Current Opinion in Psychiatry 20 (2007): 17-22.

Steffens, D. C. "Prevalence of Depression and its Treatment in an Elderly Population: The Cache County Study." Archives of General Psychiatry 57 (2000): 601-607.

Talmage, J. B. , J. M. Melhorn, and M. H. Hyman, eds. Work Ability and Return to Work, AMA Guides to the Evaluation of. Second ed. Chicago: AMA Press, 2011.

Weissman, Myrna M., et al. "Cross-national Epidemiology of Major Depression and Bipolar Disorder." Journal of American Medical Association 293-299.

Source: Medical Disability Advisor

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