Loneliness refers to the subjective experience of insufficient, unsatisfying, or emotionally unavailable social relationships. It arises when a person's desired level of closeness, belonging, or connection does not match their actual relational experience.
Loneliness is not the same as being alone. A person may feel lonely among others, or experience solitude as neutral, restorative, or meaningful. Loneliness should also be distinguished from social isolation: loneliness reflects perceived relationship quality, while social isolation refers to the objective lack of social contacts, support, or network size.
General loneliness measures assess the overall subjective sense of lacking meaningful social connection. They are useful when the goal is to estimate the general intensity of loneliness rather than separate its emotional, social, developmental, or context-specific forms.
The Loneliness Scale (UCLA, UCLA-R, UCLA-3), is the most widely used measure of global loneliness, which assesses the overall intensity of perceived social disconnection and dissatisfaction with relationships.
The Three-Item Loneliness Scale is a brief measure derived from the UCLA Scale. It assesses feeling isolated, left out, and lacking companionship, making it suitable for large-scale surveys and brief screening contexts.
The ALONE Scale is a brief clinical measure developed to screen for severe loneliness in older adults. Its concise format makes it useful in healthcare and geriatric settings.
These instruments distinguish between different sources and forms of loneliness. Emotional loneliness is linked to the absence of close attachment or intimate bonds, while social loneliness reflects a lack of belonging, companionship, or integration into a broader social network.
The De Jong Gierveld Loneliness Scale assesses these two dimensions directly. Emotional loneliness reflects the absence of a close, intimate attachment figure, whereas social loneliness refers to the lack of a broader social network or sense of belonging.
Some measures also assess loneliness in specific relational domains, such as family, friendship, romantic relationships, or broader community life.
The Social and Emotional Loneliness Scale for Adults (SELSA, SELSA-S) assess loneliness across romantic, family, and social domains. These instruments provide a differentiated profile of where interpersonal deficits are most pronounced.
The Differential Loneliness Scale (DLS) distinguishes between multiple relational domains, although it is less common in contemporary research.
The Preference for Solitude Scale (PSS) assesses individual differences in the preference for spending time alone rather than with other people.
The Motivation for Solitude Scale (MSS-SF) assesses reasons for spending time alone, distinguishing more self-determined and less self-determined motivations for solitude.
Loneliness in children and adolescents is often assessed in relation to peer acceptance, friendship quality, school belonging, and social dissatisfaction. Developmental measures may rely on age-appropriate language and include both subjective loneliness and difficulties in peer relationships.
The Loneliness and Social Dissatisfaction Questionnaire assesses feelings of loneliness, perceived social adequacy, and dissatisfaction with peer relationships. It provides a developmentally sensitive perspective on loneliness in younger populations.
The Loneliness and Aloneness Scale for Children and Adolescents (LACA) assesses multiple aspects of loneliness and aloneness in children and adolescents, including experiences related to parents and peers.
The Peer Network and Dyadic Loneliness Scale (PNDLS) distinguishes between loneliness related to the broader peer group and loneliness related to the absence of a close friendship.
These measures focus on objective or behavioral aspects of social disconnectedness, such as limited social networks, lack of support, withdrawal from social life, or extreme avoidance of social participation. They are related to loneliness but should not be interpreted as direct equivalents.
The Lubben Social Network Scale (LSNS) and the Berkman-Syme Social Network Index quantify the size and frequency of social contacts. These measures are especially relevant in aging and epidemiological research, where social isolation is studied as a risk factor for health outcomes.
The Hikikomori Questionnaire (HQ-25) assesses severe social withdrawal and hikikomori-related features, including isolation, reduced social participation, and limited emotional support.
Social exclusion and ostracism describe situations in which a person feels ignored, rejected, excluded, or treated as if they do not belong.
The Ostracism Experience Scale (OES-A) assesses perceived experiences of being ignored, excluded, or left out by others. It is relevant to interpersonal functioning, social rejection, loneliness, and social distress.
⇒ Attachment. Insecure attachment may contribute to chronic loneliness, difficulties seeking closeness, and fear of rejection or abandonment.
⇒ Anxiety. Social anxiety can increase loneliness through avoidance of social situations, fear of evaluation, and reduced social participation.
⇒ Depression. Loneliness often co-occurs with depressive symptoms, but it reflects perceived social disconnection rather than mood disturbance alone.
⇒ Social Attitudes. Belongingness, inclusion, acceptance, and perceived social value overlap with loneliness but describe broader social-evaluative experiences.
⇒ Existential Concerns. Some forms of loneliness are existential rather than primarily interpersonal and are considered in the Existential Concerns domain.
Loneliness-related instruments should be interpreted as assessing subjective social connection rather than the mere presence or absence of other people. A high loneliness score may reflect lack of intimacy, weak belonging, insufficient social support, dissatisfaction with specific relationships, or a broader sense of disconnection.
Different measures emphasize different aspects of this experience. General scales estimate overall loneliness, multidimensional scales distinguish emotional and social components, developmental instruments focus on peer and school contexts, and isolation measures describe objective or behavioral disconnection.
A profile-based interpretation should therefore consider whether the main issue is emotional loneliness, social loneliness, developmental peer difficulties, lack of social network, withdrawal from social life, or existential loneliness. These forms may overlap, but they have different meanings and may require different kinds of interpretation.