Depression refers to a state characterized by persistent low mood, reduced interest or pleasure, and a range of cognitive, emotional, behavioral, and somatic symptoms. It may include sadness, hopelessness, fatigue, sleep or appetite changes, reduced motivation, and difficulty concentrating.
Depressive reactions may occur in response to life events, but sustained or severe symptoms can significantly impair functioning. Depression is usually understood as a multidimensional construct rather than a single emotional state.
These measures assess the overall severity of depressive symptoms, including low mood, loss of interest, fatigue, hopelessness, cognitive difficulties, sleep or appetite changes, and impairment in everyday functioning. They are useful for broad screening, monitoring, and comparison of depressive symptom levels.
The Beck Depression Inventory (BDI) is one of the most established measures of depressive symptoms, covering cognitive, affective, and somatic aspects of depression.
The Patient Health Questionnaire PHQ-9 is a brief screening instrument widely used in clinical, medical, and general population settings.
The Center for Epidemiologic Studies Depression Scale (CES-D, CESD-R), is widely used in population-based research and focuses on depressive affect, somatic symptoms, interpersonal difficulties, and reduced positive affect.
The PROMIS Depression assess depressive symptoms within the PROMIS emotional distress framework.
The Clinically Useful Depression Outcome Scale (CUDOS) is a brief measure of depressive symptom severity designed for clinical use and outcome monitoring. It assesses depressive symptoms over the past week.
The Overall Depression Severity and Impairment Scale (ODSIS) is a brief transdiagnostic measure of depression severity and related functional impairment over the past week.
The Inventory of Depressive Symptomatology (IDS, QIDS) provides a broader self-report assessment of depressive symptoms aligned with diagnostic criteria.
The Zung Self-Rating Depression Scale (SDS) is an early measure assessing affective and somatic symptoms of depression.
○ The Burns Depression Checklist is a symptom checklist introduced in David Burns's popular books on cognitive therapy.
⇒ Measures that assess depression together with anxiety or general distress – such as the HADS, PHQ-4, and DASS – are considered in General Clinical Screening, where depression is assessed as part of broader internalizing or general psychological distress.
These instruments assess depressive symptoms in children and adolescents using developmentally appropriate formats. In younger populations, depression may be expressed not only through sadness, but also through irritability, withdrawal, school difficulties, somatic complaints, reduced motivation, or changes in behavior.
The Center for Epidemiologic Studies Depression Scale for Children (CES-DC) – an adapted version of widely used CES-DC scale.
The Mood and Feelings Questionnaire (MFQ, SMFQ) assesses depressive symptoms in children and adolescents, capturing affective, cognitive, and behavioral features.
The Revised Child Anxiety and Depression Scale (RCADS-25) assesses symptoms of anxiety disorders and depression in children and adolescents, providing a broader profile of internalizing symptoms.
The Children's Depression Inventory (CDI) assesses depressive symptoms in children and adolescents, including negative mood, interpersonal problems, ineffectiveness, anhedonia, and negative self-esteem. ©
The Columbia DISC Depression Scale is primarily a child and adolescent depression screener, but it includes items related to death thoughts and suicidal behavior.
These instruments assess cognitive patterns that may contribute to depressive vulnerability or maintain depressive states: hopelessness, negative explanatory style, sensitivity to depressive triggers, and interpersonal-cognitive schemas such as sociotropy and autonomy. They focus on processes related to depression rather than symptom severity alone.
The Beck Hopelessness Scale (BHS) assesses negative expectations about the future, a central cognitive component of depression and suicide risk assessment. ©
The Leiden Index of Depression Sensitivity (LEIDS-R) assesses cognitive reactivity to sad mood, reflecting the tendency for negative thinking patterns to become activated when mood decreases.
The Depressive Experiences Questionnaire (DEQ) assesses personality-related depressive styles, especially dependency, self-criticism, and efficacy.
The Cognitive Style Questionnaire (CSQ-SF) assesses negative cognitive style associated with vulnerability to depression and anxiety. It captures tendencies to interpret negative events in terms of stable and global causes, serious consequences, and negative implications for self-worth.
The Sociotropy-Autonomy Scale (SAS) assesses two personality-related vulnerability patterns associated with depression: sociotropy, involving excessive dependence on interpersonal approval, and autonomy, involving strong concerns with independence, control, and achievement.
Anhedonia refers to reduced interest in, motivation for, or enjoyment of rewarding experiences. These measures assess hedonic capacity, reward responsiveness, anticipatory pleasure, consummatory pleasure, social pleasure, and physical pleasure as important components of depressive and related conditions.
The Snaith-Hamilton Pleasure Scale (SHAPS) assesses hedonic capacity and reduced ability to experience pleasure from typically enjoyable activities and experiences.
The Dimensional Anhedonia Rating Scale (DARS) assesses interest, motivation, effort, and enjoyment across several domains of rewarding activity.
The Revised Social Anhedonia Scale (RSAS) assesses diminished interest in and enjoyment of social relationships, affiliation, and interpersonal interactions.
The Revised Physical Anhedonia Scale (RPAS) assesses reduced enjoyment of sensory, physical, and aesthetic experiences that are typically experienced as pleasurable.
The Fawcett-Clark Pleasure Scale (FCPS) assesses the anticipated capacity to experience pleasure and enjoyment from a variety of everyday activities and experiences.
The Anticipatory and Consummatory Interpersonal Pleasure Scale (ACIPS) assesses the capacity to anticipate and experience pleasure derived from social and interpersonal interactions.
The Temporal Experience of Pleasure Scale (TEPS) distinguishes between anticipatory pleasure and consummatory pleasure, providing a more differentiated assessment of anhedonia.
The Behavioral Activation for Depression Scale (BADS) assesses behavioral activation and avoidance patterns, including engagement in goal-directed and rewarding activities.
Apathy describes reduced initiative, goal-directed behavior, emotional involvement, and motivation. These measures assess diminished activity, indifference, lack of drive, reduced planning, and difficulty initiating or sustaining actions, which may occur in depression but also in neurological, developmental, or other clinical contexts.
The Apathy Evaluation Scale (AES) assesses reduced motivation, diminished initiative, emotional indifference, and decreased goal-directed behavior.
The Lille Apathy Rating Scale (LARS) assesses different manifestations of apathy, including reduced initiative, lack of interest, emotional blunting, and decreased engagement in everyday activities.
The Dimensional Apathy Scale (DAS) assesses multiple forms of apathy, distinguishing executive, emotional, and initiation-related motivational difficulties.
The Starkstein Apathy Scale (SAS) assesses reduced motivation, diminished interest, lack of initiative, and emotional indifference commonly associated with neurological and psychiatric conditions.
These measures are designed for specific groups or contexts in which depressive symptoms may have distinctive forms or assessment needs, such as postnatal depression, geriatric depression, or male-pattern depressive symptoms.
The Male Depression Risk Scale (MDRS-22) assesses externalizing and non-typical symptoms of depression, such as anger, risk-taking, emotional suppression, and substance-related coping.
The Gotland Scale of Male Depression (GSMD) assesses depression-related symptoms that may be more typical or more visible in men, including irritability, anger, stress, anxiety, alcohol use, and externalizing behavior. It was developed within the “male depression” framework to improve recognition of depressive presentations that may be missed by standard depression measures.
The Geriatric Depression Scale (GDS) is designed for older adults and reduces emphasis on somatic symptoms that may overlap with aging or physical illness.
Clinician-rated measures are completed by a trained specialist and are commonly used in professional assessment, treatment monitoring, and clinical trials.
The Hamilton Depression Rating Scale (HDRS/Ham-D) is a clinician-rated measure of depression severity, with emphasis on mood, guilt, sleep, somatic symptoms, anxiety, and psychomotor changes.
The Montgomery-Asberg Depression Rating Scale (MADRS) is a clinician-rated measure of depressive symptom severity designed to be sensitive to changes during treatment.
These instruments assess grief reactions and prolonged or complicated grief after loss. Grief may overlap with depression through sadness, withdrawal, sleep problems, and loss of interest, but it is a distinct process centered on attachment, separation, longing, and adaptation to loss.
The Inventory of Complicated Grief (ICG) assesses prolonged and maladaptive grief reactions, including yearning, difficulty accepting the loss, and impairment.
The Prolonged Grief Disorder Scale (PG-13-R) is a measure for assessing symptoms of prolonged grief disorder, including yearning, emotional pain, avoidance, numbness, loneliness, and impairment after bereavement.
The Hogan Grief Reaction Checklist (HGRC) assesses grief-related responses across emotional, cognitive, and personal-growth dimensions.
The Grief Experience Questionnaire (GEQ) assesses grief reactions after bereavement, including emotional distress, guilt, anger, social isolation, loss of control, rumination, depersonalization, and somatic reactions.
⇒ Anxiety. Depression and anxiety frequently co-occur and may share avoidance, rumination, tension, sleep disturbance, and broader internalizing distress.
⇒ Stress. Stressful life events, chronic strain, overload, and exhaustion may contribute to depressive symptoms or intensify existing depression.
⇒ Existential Concerns. Hopelessness, loss of meaning, alienation, crisis, and death-related distress may overlap with depressive experience.
⇒ Emotion Regulation. Difficulties with rumination, avoidance, suppression, and regulation of negative affect may maintain or intensify depressive states.
Depression is a heterogeneous construct involving mood, cognition, motivation, behavior, reward responsiveness, somatic functioning, and impairment in everyday life. Some instruments assess broad symptom severity, while others focus on specific components such as hopelessness, anhedonia, apathy, behavioral avoidance, or grief-related distress.
Assessment should distinguish between depressive symptoms, depressive vulnerability, motivational deficits, loss of pleasure, and reactions to loss. These features may co-occur, but they do not always have the same psychological meaning or clinical implications.
Interpretation should also consider age, life stage, gender, medical conditions, stress, anxiety, grief, and broader internalizing distress. Instruments that screen depression together with anxiety, stress, or general distress are best treated as general clinical screening measures rather than depression-specific tools.
Together, these measures help describe how depressive states are expressed, what processes may maintain them, and which aspects of experience – mood, thinking, motivation, activity, pleasure, or loss – are most central in a particular case.