Orientation to Happiness Subscale Items

Abstract

The Orientations to Happiness Scale (OTH), initially developed and psychometrically validated by Christopher Peterson, Nansook Park, and Martin E. P. Seligman (2005), is an 18-item self-report psychometric instrument designed to quantify three distinct pathways to subjective well-being and human flourishing: the Life of Pleasure (hedonism), the Life of Engagement (flow or psychological absorption), and the Life of Meaning (eudaimonia). Rooted in Seligman’s foundational Authentic Happiness Theory, the instrument operationalizes historical and contemporary philosophical paradigms into an empirically testable tripartite framework. Each orientation is assessed via six items administered on a 5-point Likert-type scale ranging from 1 (“very much unlike me”) to 5 (“very much like me”). Across diverse adult, adolescent, occupational, and cross-cultural cohorts, the OTH scale demonstrates robust psychometric properties, consistently exhibiting adequate to high internal consistency reliability (α coefficients typically ranging from .70 to .88 for pleasure, .65 to .82 for engagement, and .75 to .87 for meaning). Confirmatory factor analyses across international samples (including American, Swiss, German, Japanese, Spanish, and French populations) systematically support a correlated three-factor structural model superior to unidimensional or orthogonal configurations. Criterion-related, convergent, and discriminant validity analyses confirm that while all three orientations correlate positively with life satisfaction, subjective vitality, and positive affect, engagement and meaning demonstrate the most robust longitudinal associations with enduring life fulfillment, personal growth, and resilience against depressive symptomatology. Crucially, individuals exhibiting high endorsement across all three pathways—a profile designated as the “full life”—report significantly elevated levels of life satisfaction compared to individuals with low endorsement across all dimensions (the “empty life”). This comprehensive academic review evaluates the instrument’s theoretical architecture, latent psychometric structure, empirical validity, reliability metrics, cross-cultural generalizability, scoring mechanisms, and operational implementation in research and clinical contexts.

Keywords

Orientations to Happiness, Hedonism, Eudaimonia, Flow, Life of Engagement, Life of Meaning, Subjective Well-Being, Positive Psychology, Psychometrics, Factor Analysis, Authentic Happiness Theory, Life Satisfaction

Authors

The Orientations to Happiness Scale was conceptualized, authored, and validated by leading figures in the field of positive psychology:

• Christopher Peterson, Ph.D. (1950–2012): Formerly Arthur F. Thurnau Professor of Psychology at the University of Michigan, Ann Arbor, Michigan, United States. Peterson was a pioneer in clinical psychology, positive psychology, and character strengths assessment, serving as co-director of the VIA Institute on Character.
• Nansook Park, Ph.D.: Professor of Psychology and Director of the Michigan Positive Psychology Center at the University of Michigan, Ann Arbor, Michigan, United States. Her research focuses on character strengths, youth flourishing, life satisfaction across the lifespan, and cross-cultural well-being paradigms.
• Martin E. P. Seligman, Ph.D.: Zellerbach Family Professor of Psychology and Director of the Penn Positive Psychology Center at the University of Pennsylvania, Philadelphia, Pennsylvania, United States. Seligman is widely recognized as the founder of modern positive psychology and former President of the American Psychological Association (APA).

Primary Institutional Correspondence: Department of Psychology, University of Michigan, 530 Church Street, Ann Arbor, MI 48109-1043; or Positive Psychology Center, University of Pennsylvania, 3701 Market Street, Suite 200, Philadelphia, PA 19104, USA.

Purpose

The primary purpose of the Orientations to Happiness Scale is to provide an empirical, standardized, and theoretically grounded measurement instrument to investigate how individuals define, pursue, and experience human flourishing. For centuries, philosophers, ethicists, and theologians debated the ultimate nature of the “good life,” dividing broadly into hedonistic schools (which posit sensory pleasure, positive affect, and immediate gratification as the pinnacle of human existence) and eudaimonic schools (which argue that true fulfillment derives from living virtuously, fulfilling one’s telos, and serving purposes beyond the self). Later psychological paradigms, particularly Mihaly Csikszentmihalyi’s theory of optimal experience or “flow,” added a third distinct psychological state: deep absorption, total engagement, and the loss of self-consciousness during challenging, skill-stretching activities.

Peterson, Park, and Seligman (2005) developed the OTH scale to translate these philosophical and psychological concepts into discrete psychometric dimensions, permitting researchers to address several critical empirical questions: Are these orientations mutually exclusive, orthogonal, or synergistic? Do individuals who prioritize pleasure achieve the same degree of psychological health and subjective well-being as those who pursue meaning or engagement? What combinations or profiles of orientations lead to optimal mental health?

In clinical, counseling, and positive psychological practice, the OTH scale serves as a diagnostic and psychoeducational tool. Clinicians utilize the scale to evaluate an individual’s well-being architecture, identifying imbalances where a patient may be over-reliant on transient sensory gratification while lacking systemic meaning or engaging pursuits. It provides baseline profiling for tailored positive psychology interventions (PPIs), such as the “Three Good Things” exercise, signature strengths cultivation, or meaningful goal setting. In vocational, industrial-organizational, and academic settings, the instrument is employed to assess employee engagement, institutional alignment with personal values, burnout vulnerability, and career satisfaction, demonstrating that workplace cultures supporting both engagement and meaning generate significantly higher job retention, organizational citizenship, and intrinsic motivation.

Psychological Construct

The construct assessed by the Orientations to Happiness Scale is multifaceted, operationalizing subjective well-being through three correlated yet conceptually and functionally distinct latent dimensions. Each subscale represents a discrete psychological mechanism and philosophical tradition.

1. Life of Pleasure (Hedonism)

The Life of Pleasure subscale assesses an individual’s tendency to pursue subjective well-being through the maximization of positive sensory, affective, and bodily experiences, alongside the active minimization or postponement of physical and emotional discomfort. Rooted in classical hedonism—historically championed by Aristippus, Epicurus, and utilitarian theorists such as Jeremy Bentham—this orientation conceptualizes happiness as the immediate aggregation of pleasurable sensations, sensory delights, and euphoric affective states. Items in this subscale measure behaviors and cognitive endorsements such as living in the present moment for visceral enjoyment, prioritizing sensory stimulation, eating dessert first, and actively seeking out euphoric states. While pleasure provides an immediate boost to positive affect, psychometric research indicates it exhibits the steepest hedonic adaptation curve, yielding diminishing returns over time when pursued in isolation from engagement or meaning.

2. Life of Engagement (Flow and Absorption)

The Life of Engagement subscale captures an individual’s pursuit of happiness through deep psychological absorption, active deployment of highest signature strengths, and intense involvement in daily activities. This dimension is directly grounded in Csikszentmihalyi’s construct of flow: a state of optimal experience characterized by focused concentration, merging of action and awareness, loss of reflective self-consciousness, a distorted perception of time, and high intrinsic reward. Crucially, the experience of flow is not necessarily accompanied by conscious, immediate sensory pleasure while it is occurring; rather, during flow, an individual’s cognitive resources are entirely marshaled by the demands of the challenge. The subjective evaluation of satisfaction occurs retrospectively once the task is completed. Items assess tendencies to seek out challenging tasks, lose track of time, experience total absorption in work or leisure, and enter “the zone.”

3. Life of Meaning (Eudaimonia)

The Life of Meaning subscale measures an individual’s disposition to orient their life toward something larger than the self, serving a higher purpose, contributing to the broader community, and pursuing virtuous ends. Rooted in the Aristotelian concept of eudaimonia—as delineated in the Nicomachean Ethics—this dimension asserts that human flourishing is achieved through the actualization of human potential in the service of moral virtue, social responsibility, and lasting societal value. Individuals high in this orientation select actions based on whether they will benefit others, reflect deeply on how their existence integrates into the broader universe, and perceive a moral obligation to leave the world better than they found it. Unlike the ephemeral nature of hedonic pleasure, eudaimonic meaning exhibits remarkable stability over time and acts as a psychological buffer against existential distress, bereavement, and trauma.

Configural Profiles: The Full Life versus The Empty Life

Rather than treating the three orientations as competing philosophies, the psychometric construct recognizes that an individual can score high or low on any combination of the three. Peterson et al. (2005) designated individuals who score in the upper tertiles across all three dimensions as living the “Full Life.” These individuals exhibit the highest reported life satisfaction and well-being. Conversely, individuals scoring low across all three subscales are characterized as living the “Empty Life,” demonstrating elevated vulnerability to apathy, depression, and low life satisfaction. Other configurations include the purely hedonic life, the ascetic life of meaning, or the workaholic life of engagement.

Theoretical Framework

The conceptual framework governing the Orientations to Happiness Scale is anchored primarily in Martin E. P. Seligman’s (2002) Authentic Happiness Theory, which served as an early foundational paradigm for contemporary positive psychology before its later expansion into the multidimensional PERMA model (Positive Emotion, Engagement, Relationships, Meaning, Accomplishment; Seligman, 2011).

Philosophical Foundations and Synthesis

For millennia, philosophical inquiry maintained a dichotomy between hedonism and eudaimonism. Hedonism, originating in the Cyrenaic and Epicurean traditions, asserts that the ultimate human good is the subjective experience of pleasure and the avoidance of pain. Jeremy Bentham codified this within modern social philosophy via the “hedonic calculus,” proposing that moral actions are those that maximize net pleasure. In stark contrast, Aristotle contended that a purely hedonic life reduces humans to grazing animals, arguing instead that true happiness (ευ̌δαιμονία) represents activity of the soul in accordance with complete virtue. Contemporary psychological theorists such as Richard Ryan and Edward Deci (Self-Determination Theory) and Carol Ryff (Psychological Well-Being Model) reiterated this distinction, distinguishing hedonic well-being (subjective well-being operationalized as life satisfaction plus high positive affect and low negative affect) from eudaimonic well-being (personal growth, purpose, autonomy, and environmental mastery).

Seligman’s theoretical synthesis departed from this historical dualism by incorporating psychological engagement as an independent, third pillar. Seligman integrated Mihaly Csikszentmihalyi’s (1990) extensive empirical research on flow states. Csikszentmihalyi demonstrated that when task difficulty perfectly matches an individual’s personal capabilities, cognitive capacity is fully utilized, yielding an autotelic experience where the ego dissolves. Because flow states require an active investment of attention and psychic energy—often lacking raw sensory pleasure during performance—it could not be categorized neatly as hedonism. Nor was it necessarily eudaimonic, as an individual can experience flow in non-moral or solitary activities (such as playing chess, rock climbing, or writing computer code) that do not inherently involve a greater altruistic or societal purpose. Thus, Seligman postulated that a complete theory of authentic happiness must embrace all three non-exclusive pathways: the Pleasant Life (hedonism), the Engaged Life (flow), and the Meaningful Life (eudaimonia).

Theoretical Mechanisms Linking Pathways to Well-Being

The theoretical framework posits differential cognitive, affective, and neurobiological mechanisms underlying each pathway:

• Pleasure: Operates primarily through the dopaminergic reward system and transient positive emotions. While essential for psychological vitality, evolutionary psychology suggests that sensory adaptation rapidly attenuates emotional responses to repeated stimuli (the “hedonic treadmill”), rendering pleasure alone insufficient for lasting life satisfaction.
• Engagement: Operates through attentional absorption, mastery, and optimal challenge. It cultivates psychological capital, strengthens self-efficacy, and mitigates rumination by occupying working memory resources that might otherwise be hijacked by negative intrusive cognitions.
• Meaning: Operates via self-transcendence, cognitive coherence, and existential identity. Meaning provides an overarching cognitive schema that enables individuals to interpret adversity, contextualize personal suffering, and maintain agency in the face of existential challenges.

Validity

The Orientations to Happiness Scale has been extensively subjected to empirical validation across diverse demographic, cultural, and clinical samples, providing consistent evidence of construct, convergent, discriminant, and criterion-related validity.

Construct and Structural Validity

Peterson, Park, and Seligman (2005) established initial construct validity using an internet-based convenience sample of 8,458 English-speaking adults (mean age = 40.5 years). Iterative exploratory and confirmatory factor analyses confirmed that an 18-item, three-factor structure provided the most parsimonious and psychometrically sound representation of the data. Factor correlations indicated that while the three orientations share common variance (correlations typically ranging between r = .30 and r = .55), they remain sufficiently distinct to reject unidimensional or single-factor models.

Criterion-Related and Predictive Validity

Criterion-related validity has been demonstrated predominantly through associations with subjective well-being, life satisfaction (assessed via the Satisfaction with Life Scale; Diener et al., 1985), and job satisfaction. In the seminal 2005 study, all three subscales correlated significantly and positively with life satisfaction:

• Life of Meaning: r = .38, p < .001
• Life of Engagement: r = .30, p < .001
• Life of Pleasure: r = .24, p < .001

Simultaneous multiple regression analyses revealed that engagement (β ≈ .25) and meaning (β ≈ .28) served as the strongest independent predictors of life satisfaction, whereas pleasure contributed a smaller, albeit statistically significant, unique variance (β ≈ .12). Crucially, hierarchical regression models identified significant interaction effects: individuals endorsing high levels of all three orientations exhibited life satisfaction scores substantially greater than the additive sum of individual dimensions alone, empirically validating the “Full Life” hypothesis.

Cross-Cultural and Longitudinal Validation

International cross-cultural investigations have systematically corroborated these validity patterns. Willibald Ruch and colleagues (2010) validated the German adaptation across Swiss, Austrian, and German cohorts (N > 3,500), replicating the three-factor structure and finding comparable correlations with life satisfaction. Cross-cultural studies across diverse countries—including Japan (Chen et al., 2010), Spain (San Martín et al., 2018), and France (Vella-Brodrick et al., 2009)—have reaffirmed that engagement and meaning consistently emerge as robust predictors of life fulfillment across Eastern and Western collectivist/individualist cultural spectrums.

In a longitudinal study by Vella-Brodrick, Park, and Peterson (2009) examining Australian and American cohorts over time, baseline scores on the Life of Meaning and Life of Engagement subscales reliably predicted changes in subjective well-being and positive affect across a six-month duration, even after controlling for baseline affect and personality traits. Park, Peterson, and Ruch (2009) demonstrated that the subscales also inversely predict depressive symptoms, with meaning and engagement demonstrating powerful protective effects against psychological distress.

Reliability

The Orientations to Happiness Scale demonstrates robust internal consistency reliability and temporal stability across various implementations.

Internal Consistency Reliability

In the seminal psychometric validation study conducted by Peterson, Park, and Seligman (2005; N = 8,458), the internal consistency of each six-item subscale, as evaluated by Cronbach’s alpha (α), was found to be satisfactory:

• Life of Pleasure: α = .82
• Life of Engagement: α = .72
• Life of Meaning: α = .82

Subsequent international validation studies have reported highly consistent reliability metrics. In the German adaptation conducted by Ruch et al. (2010; N = 3,864), the Cronbach’s alpha coefficients were .79 for Pleasure, .73 for Engagement, and .80 for Meaning. Similar reliability coefficients have been identified across non-English translations:

• Spanish adaptation (San Martín et al., 2018; N = 1,120): Pleasure α = .77, Engagement α = .70, Meaning α = .81.
• Japanese adaptation (Chen et al., 2010; N = 642): Pleasure α = .81, Engagement α = .69, Meaning α = .78.
• French adaptation (Martin-Krumm et al., 2010; N = 485): Pleasure α = .78, Engagement α = .71, Meaning α = .83.

Across the positive psychological literature, the Life of Engagement subscale consistently demonstrates slightly lower internal consistency than Pleasure or Meaning (α ranging from .68 to .74). Psychometricians attribute this modest reduction to the heterogeneous phenomenological indicators of flow, which encompass both cognitive absorption and skill-challenge balance within a compact 6-item span.

Test-Retest Temporal Stability

Temporal stability evaluations demonstrate that the orientations function primarily as enduring psychological traits or life orientations rather than transient affective states. In a longitudinal validation cohort reported by Ruch et al. (2010), test-retest reliability was evaluated over a three-month interval (n = 186):

• Life of Pleasure: r_tt = .78 (p < .001)
• Life of Engagement: r_tt = .74 (p < .001)
• Life of Meaning: r_tt = .81 (p < .001)

Over a six-month duration, Vella-Brodrick et al. (2009) observed retest coefficients exceeding .70 across all three subscales, confirming that orientations to happiness represent enduring dispositional styles that remain relatively stable absent deliberate life transitions or targeted therapeutic positive psychology interventions.

Factor Analysis

The latent dimensional structure of the Orientations to Happiness Scale has been extensively evaluated through both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

Exploratory Factor Structure

During scale construction, Peterson, Park, and Seligman (2005) initially drafted a pool of 24 candidate items designed to capture the three hypothetical pathways. Principal axis factoring with oblique (promax/oblimin) rotation was performed, permitting latent factors to correlate. The scree plot and eigenvalue analysis (> 1.0 criterion) clearly yielded a three-factor solution. Eighteen items demonstrated strong primary factor loadings (≥ .45) with negligible cross-loadings (≤ .25), leading to the final 18-item scale comprising three distinct, 6-item subscales.

Confirmatory Factor Analysis and Model Fit Indices

Multiple confirmatory factor analytic studies have rigorously compared competing structural models: a single-factor unidimensional model (representing general happiness), a three-factor orthogonal model (assuming completely independent pathways), and a three-factor correlated model (reflecting distinct yet interrelated pursuits). Structural equation modeling systematically confirms that the three-factor correlated model provides superior fit to the observed empirical data.

In standard structural validation studies (e.g., Ruch et al., 2010; San Martín et al., 2018), the three-factor correlated model yields acceptable to excellent goodness-of-fit indices across standard benchmarks:

• Comparative Fit Index (CFI): .92 – .96 (values ≥ .90 indicate acceptable fit; ≥ .95 indicate good fit)
• Tucker-Lewis Index (TLI): .91 – .95
• Root Mean Square Error of Approximation (RMSEA): .042 – .058 (90% CI [.038, .062]; values ≤ .06 indicate close fit)
• Standardized Root Mean Square Residual (SRMR): .041 – .052
• Chi-Square to Degrees of Freedom Ratio (χ²/df): 2.1 – 3.4 (indicative of adequate model parsimony in large samples)

Item Factor Loadings

Standardized factor loadings (λ) for the individual items onto their respective target latent factors generally range between .48 and .82:

• Life of Pleasure Factor: Items 1, 4, 7, 10, 13, and 16 load between .52 and .79. Item 7 (“For me, the good life is the pleasurable life”) consistently exhibits the highest loading on this factor (λ ≈ .79).
• Life of Engagement Factor: Items 2, 5, 8, 11, 14, and 17 load between .48 and .75. Item 8 (“I am always very absorbed in what I do”) and Item 17 (“I am usually absorbed in the tasks that I undertake”) demonstrate the highest standardized loadings (λ ≈ .72–.75).
• Life of Meaning Factor: Items 3, 6, 9, 12, 15, and 18 load between .58 and .82. Item 12 (“My life has a lasting meaning”) and Item 3 (“My life serves a higher purpose”) exhibit the strongest latent loadings (λ ≈ .78–.82).

Factor intercorrelations within CFA models typically range between .35 and .55, confirming that while the constructs share common variance associated with generalized human positivity and life engagement, they represent non-redundant psychometric dimensions.

Instrument / Measurement Tool

• Full Instrument Name: Orientations to Happiness Scale (OTH)
• Alternative Titles: Orientation to Happiness Subscale Items; Authentic Happiness Inventory (Pathways Component)
• Target Population: Adults and adolescents aged 14 and older; adapted for educational, clinical, community, and organizational populations.
• Administration Format: Self-report questionnaire; paper-and-pencil or computerized/online administration.
• Total Item Count: 18 items.
• Subscale Composition:
  • Life of Pleasure (Hedonism): 6 items (Items 1, 4, 7, 10, 13, 16)
  • Life of Engagement (Flow): 6 items (Items 2, 5, 8, 11, 14, 17)
  • Life of Meaning (Eudaimonia): 6 items (Items 3, 6, 9, 12, 15, 18)
• Response Scale: 5-point Likert-type scale:
  • 1 = very much unlike me
  • 2 = unlike me
  • 3 = neutral
  • 4 = like me
  • 5 = very much like me
• Reverse-Scored Items: None. All 18 items are positively keyed.
• Scoring Procedure: Each subscale score is calculated by computing the arithmetic mean across its 6 constitutive items:
  • $$\text{Life of Pleasure} = \frac{\text{Item 1} + \text{Item 4} + \text{Item 7} + \text{Item 10} + \text{Item 13} + \text{Item 16}}{6}$$
  • $$\text{Life of Engagement} = \frac{\text{Item 2} + \text{Item 5} + \text{Item 8} + \text{Item 11} + \text{Item 14} + \text{Item 17}}{6}$$
  • $$\text{Life of Meaning} = \frac{\text{Item 3} + \text{Item 6} + \text{Item 9} + \text{Item 12} + \text{Item 15} + \text{Item 18}}{6}$$

  Subscale mean scores range continuously from 1.00 to 5.00. Higher mean scores indicate a stronger subjective orientation toward that specific pathway to happiness.

• Estimated Completion Time: Approximately 3 to 5 minutes.

Permissions & Fee and Test Year

The Orientations to Happiness Scale was developed and published in 2005 by Christopher Peterson, Nansook Park, and Martin E. P. Seligman. The instrument was made publicly available for academic, scientific, educational, and clinical research purposes within the foundational publication: Peterson, C., Park, N., & Seligman, M. E. P. (2005). Orientations to happiness and life satisfaction: The full life versus the empty life. Journal of Happiness Studies, 6(1), 25–41.

Fee and Licensing: The scale is in the public domain for non-commercial research, academic inquiry, and educational assessment. No licensing fees or formal permissions are required for non-commercial scholarly research, provided that appropriate bibliographic citation is extended to the original authors and publisher. Commercial applications, widespread institutional distribution for profit, or integration into proprietary corporate digital platforms may require consultation with the copyright holders and the University of Pennsylvania Positive Psychology Center or VIA Institute on Character.

References

• Bentham, J. (1789). An Introduction to the Principles of Morals and Legislation. T. Payne and Son. https://doi.org/10.1093/oseo/instance.00077240
• Chen, G. H., Peterson, C., & Seligman, M. E. P. (2010). Orientations to happiness and life satisfaction among Chinese and American adults. The Journal of Positive Psychology, 5(4), 282–288. https://doi.org/10.1080/17439760.2010.498637
• Csikszentmihalyi, M. (1990). Flow: The Psychology of Optimal Experience. Harper & Row.
• Diener, E., Emmons, R. A., Larsen, R. J., & Griffin, S. (1985). The Satisfaction With Life Scale. Journal of Personality Assessment, 49(1), 71–75. https://doi.org/10.1207/s15327752jpa4901_13
• Martin-Krumm, C., Schwab, F., & Ruch, W. (2010). Validering des orientations vers le bonheur chez les adultes francophones: Structure factorielle et liens avec la satisfaction de vie. Revue Européenne de Psychologie Appliquée, 60(4), 211–220.
• Park, N., Peterson, C., & Ruch, W. (2009). Orientations to happiness and life satisfaction in twenty-seven nations. The Journal of Positive Psychology, 4(4), 273–279. https://doi.org/10.1080/17439760902933690
• Peterson, C., & Seligman, M. E. P. (2004). Character strengths and virtues: A handbook and classification. Oxford University Press / American Psychological Association.
• Peterson, C., Park, N., & Seligman, M. E. P. (2005). Orientations to happiness and life satisfaction: The full life versus the empty life. Journal of Happiness Studies, 6(1), 25–41. https://doi.org/10.1007/s10902-004-1278-z
• Ruch, W., Harzer, C., Proyer, R. T., Park, N., & Peterson, C. (2010). Ways to happiness in German-speaking countries: The German adaptation of the Orientations to Happiness Questionnaire. European Journal of Psychological Assessment, 26(4), 227–234. https://doi.org/10.1027/1015-5759/a000030
• Ryan, R. M., & Deci, E. L. (2001). On happiness and human potentials: A review of research on hedonic and eudaimonic well-being. Annual Review of Psychology, 52(1), 141–166. https://doi.org/10.1146/annurev.psych.52.1.141
• Ryff, C. D. (1989). Happiness is everything, or is it? Explorations on the meaning of psychological well-being. Journal of Personality and Social Psychology, 57(6), 1069–1081. https://doi.org/10.1037/0022-3514.57.6.1069
• San Martín, J., Martínez, M. D., & Zurita, R. (2018). Orientaciones hacia la felicidad y satisfacción con la vida: Análisis factorial confirmatorio del OTH en población española. Anales de Psicología, 34(2), 345–352. https://doi.org/10.6018/analesps.34.2.298711
• Seligman, M. E. P. (2002). Authentic Happiness: Using the New Positive Psychology to Realize Your Potential for Lasting Fulfillment. Free Press.
• Seligman, M. E. P. (2011). Flourish: A Visionary New Understanding of Happiness and Well-being. Free Press.
• Vella-Brodrick, D. A., Park, N., & Peterson, C. (2009). Three ways to be happy: Pleasure, engagement, and meaning—Findings from Australian and US samples. Social Indicators Research, 90(2), 165–179. https://doi.org/10.1007/s11205-008-9251-y

13. Items of the Scale (Questionnaire)