Spiritual Attitude and Involvement List (SAIL)

1. Abstract

The Spiritual Attitude and Involvement List (SAIL) is a multidimensional self-report instrument developed to quantify spirituality as a universal human phenomenon, operationalized independently from traditional religious dogma, institutional affiliation, or theological presuppositions. Developed and validated by de Jager Meezenbroek et al. (2012), the SAIL addresses a critical methodological challenge in psychometrics and psycho-oncology: the confounding of spiritual well-being scales with general mental health, psychological functioning, and explicit religious practices. The scale comprises 26 items structured across seven primary subscales grouped conceptually into three second-order dimensions: Connectedness with Oneself (encompassing Meaningfulness, Trust, and Acceptance), Connectedness with Others and Nature (encompassing Caring for Others and Connectedness with Nature), and Connectedness with the Transcendent (encompassing Transcendent Experiences and Spiritual Activities).

Psychometrically, the instrument utilizes a differentiated 6-point scoring schema: items 1 through 18 measure intensity or endorsement on an anchor ranging from 1 (not at all) to 6 (to a very high degree), whereas items 19 through 26 assess occurrence frequency ranging from 1 (never) to 6 (very often). Empirical evaluations demonstrated robust internal consistency across heterogeneous samples, including healthy community adults, cancer survivors, and individuals interested in spirituality, with subscale Cronbach’s alpha values ranging between .74 and .89, and overall instrument reliability consistently exceeding .90. Confirmatory factor analysis demonstrates excellent structural validity, verifying both the seven-factor primary architecture and hierarchical higher-order structures. The SAIL provides researchers and clinicians with a psychometrically rigorous instrument capable of elucidating the role of universal existential and spiritual attitudes in physical illness, psychological adaptation, and end-of-life palliative care.

2. Keywords

Spiritual Attitude and Involvement List, SAIL, universal spirituality, psychometrics, existential meaning, psycho-oncology, transcendent experiences, connectedness, palliative care, health psychology

3. Authors

The Spiritual Attitude and Involvement List was developed by a multidisciplinary team of Dutch researchers specializing in psychology, oncology, and behavioral medicine:

• Evelyne C. de Jager Meezenbroek, PhD: Helen Dowling Institute, Centre for Psycho-Oncology, Bilthoven, The Netherlands.
• Bert Garssen, PhD: Research Director, Helen Dowling Institute, Centre for Psycho-Oncology, Bilthoven, The Netherlands.
• Miriam van den Berg, MSc: Helen Dowling Institute, Centre for Psycho-Oncology, Bilthoven, The Netherlands.
• Gerda Tuytel, MSc: Helen Dowling Institute, Centre for Psycho-Oncology, Bilthoven, The Netherlands.
• Dirk van Dierendonck, PhD: Associate Professor of Human Resource Management and Organizational Psychology, Rotterdam School of Management, Erasmus University Rotterdam, The Netherlands.
• Adriaan Visser, PhD: Helen Dowling Institute, Centre for Psycho-Oncology, Bilthoven, The Netherlands; and European Institute for Health and Social Services, Rotterdam, The Netherlands.
• Wilmar B. Schaufeli, PhD: Distinguished Professor of Work and Organizational Psychology, Department of Psychology, Utrecht University, Utrecht, The Netherlands; and KU Leuven, Belgium.

Correspondence regarding the original development of the scale was addressed to the Helen Dowling Institute, Bilthoven, The Netherlands.

4. Purpose

The primary impetus for constructing the Spiritual Attitude and Involvement List was the pervasive conceptual and methodological ambiguity in the measurement of spirituality within health sciences, psychosomatic medicine, and oncology. Prior to the development of the SAIL, the empirical landscape was dominated by two main categories of measures, both of which suffered from critical methodological limitations. First, traditional religiosity scales (such as measures of church attendance, biblical orthodoxy, or traditional theistic devotion) failed to capture the growing demographic cohort often characterized as “spiritual but not religious” (SBNR) or secular humanists who nonetheless experience profound existential depth, transcendence, and connectedness. Second, contemporary “functional” spirituality scales—most notably instruments measuring spiritual well-being or existential peace—frequently conflated spiritual constructs with mental health indicators, subjective well-being, life satisfaction, or the absence of depressive symptomatology.

This confounding produced circular or tautological research findings: when an instrument measuring spirituality includes items reflecting emotional resilience, happiness, or vitality, finding a positive correlation between spirituality and mental health is an artifact of overlapping item content (criterion contamination). The developers of the SAIL explicitly engineered the instrument to circumvent this contamination by operationalizing spirituality not as an affective outcome or psychological adjustment variable, but as an existential attitude and experiential involvement defined through universal dimensions of connectedness.

The clinical purpose of the SAIL is broad and multifaceted:

• Psycho-Oncology and Chronic Disease Management: Facilitating systematic assessment of spiritual coping resources, existential distress, and value orientations in patients confronting life-threatening diagnoses such as malignancy, progressive cardiovascular disease, or terminal illness.
• Palliative and End-of-Life Care: Assisting multidisciplinary palliative teams—including clinical psychologists, chaplains, and social workers—in diagnosing existential anguish, identifying sources of personal reconciliation, and designing individualized pastoral and psychotherapeutic interventions.
• Psychotherapy and Counseling: Providing therapists working within existential, humanistic, cognitive-behavioral, or transpersonal frameworks an objective baseline of a patient’s existential framework, internal locus of acceptance, and relational connectivity.
• Cross-Cultural and Epidemiological Research: Offering an inclusive, non-sectarian measurement tool that can be administered without linguistic, conceptual, or philosophical bias across secular, agnostic, atheist, and traditionally religious populations.

5. Psychological Construct

The SAIL conceptualizes spirituality as a universal human capacity centered on the experience of connectedness along three distinct relational axes: connectedness with oneself, connectedness with others and nature, and connectedness with the transcendent. This tripartite conceptualization captures both cognitive attitudes and behavioral or experiential involvement. Across these three axes, the construct is differentiated into seven validated subscales:

Axis I: Connectedness with Oneself

• Meaningfulness (3 items: 4, 12, 17): Refers to the cognitive apprehension and emotional conviction that one’s existence possesses overarching significance, coherence, and directional purpose. Distinct from transient happiness, meaningfulness reflects the appraisal that one’s daily actions are anchored in a teleological framework. For example, item 17 states, “My life has meaning and purpose.”
• Trust (4 items: 1, 3, 9, 13): Characterizes a foundational existential security and confidence in one’s capacity to navigate ontological uncertainty, adversity, and existential crises without succumbing to demoralization. It is an intrinsic faith in life’s unfolding. For example, item 1 states, “I approach the world with trust,” and item 9 emphasizes, “Whatever happens, I am able to cope with life.”
• Acceptance (4 items: 6, 8, 11, 15): Involves the psychological reconciliation with human limitation, lack of absolute control, suffering, and existential vulnerability. Grounded in existential reality rather than passive fatalism, it reflects active non-resistance to inevitable existential constraints. For example, item 8 states, “I accept that I am not able to influence everything,” and item 15 asserts, “I accept that life will inevitably sometimes bring me pain.”

Axis II: Connectedness with Others and Nature

• Caring for Others (4 items: 2, 7, 16, 18): Encompasses prosocial motivation, altruism, empathy, and the desire to alleviate suffering and contribute substantively to human welfare. It reflects the realization of interpersonal interdependence. For example, item 2 specifies, “It is important to me that I can do things for others,” and item 7 captures empathy: “I am receptive to other people’s suffering.”
• Connectedness with Nature (2 items: 5, 14): Denotes an aesthetic, sensory, and spiritual resonance with the natural environment, characterized by feeling integrated into the broader biospheric ecosystem. For example, item 5 notes, “The beauty of nature moves me,” while item 14 highlights, “When I am in nature, I feel a sense of connection.”

Axis III: Connectedness with the Transcendent

• Transcendent Experiences (5 items: 19, 20, 21, 23, 25): Captures episodic, altered, or peak states of awareness wherein conventional ego boundaries dissolve, yielding direct apprehensions of unity, ultimate reality, or merging with a reality greater than oneself. Measured in terms of frequency, item 20 captures, “I have had experiences in which I seemed to merge with a power or force greater than myself,” and item 21 assesses, “I have had experiences in which all things seemed to be part of a greater whole.”
• Spiritual Activities (4 items: 10, 22, 24, 26): Represents concrete behavioral engagement in introspective, contemplative, or communal practices aimed at nurturing spiritual growth. It encompasses both structured religious behaviors and independent meditative rituals. For example, item 24 reads, “I meditate or pray, or take time in other ways to find inner peace,” while item 26 evaluates, “I attend sessions, workshops, etc. that are focused on spirituality or religion.”

6. Theoretical Framework

The conceptual framework of the SAIL synthesizes insights from humanistic psychology, transpersonal psychology, and existential psychotherapy, drawing significantly on the foundational scholarship of Viktor Frankl, Abraham Maslow, and contemporary relational models of spirituality.

Frankl’s logotherapy posits that the primary human motivational force is the “will to meaning.” According to Frankl, human beings are intrinsically motivated to discover purpose in existence, which can be actualized through experiential values (experiencing art, nature, or relationships), creative values (producing work or performing deeds), and attitudinal values (the attitude one adopts toward unavoidable suffering). The SAIL operationalizes these three value domains directly across its subscales: Meaningfulness and Caring for Others align with creative and relational values, Connectedness with Nature captures experiential values, and Acceptance reflects Frankl’s attitudinal values in the face of ontological limitations.

Maslow’s theory of self-actualization and metamotivation provides the empirical and theoretical grounding for the Transcendent Experiences subscale. In his later writings, Maslow described “peak experiences”—intense, transient occurrences of awe, ego-transcendence, cognitive integration, and profound wholeness. Maslow emphasized that peak experiences are naturalistic, universal psychological phenomena that occur in secular as well as devout individuals. The SAIL formalizes this transpersonal perspective by operationalizing transcendent occurrences (e.g., merging with a larger whole, sensing an overarching reality) without necessitating sectarian or theistic interpretations.

Furthermore, the overarching structural organizing principle of the SAIL is derived from relational models of human consciousness (e.g., Martin Buber’s dialogical philosophy of I-Thou relationships and modern psychological theories of self-transcendence). In this relational paradigm, human spiritual maturity develops across nested concentric circles: internal integration (self), horizontal belongingness (human community and ecological biosphere), and vertical or ultimate extension (the transcendent, cosmic, or divine). By categorizing seven specific psychological domains under these three distinct relational axes, the SAIL establishes a comprehensive multidimensional architecture that satisfies both clinical sensitivity and theoretical coherence.

7. Validity

The psychometric validation of the SAIL was conducted through extensive empirical investigations led by de Jager Meezenbroek et al. (2012) across three distinct sample cohorts: a normative general population sample (N = 312), a clinical cohort of cancer patients post-treatment (N = 277), and an intentional cohort of individuals actively engaged in spiritual traditions (N = 239). The findings provide robust empirical support for construct, convergent, discriminant, and predictive validity.

Construct and Factorial Validity

Construct validity was demonstrated via rigorous structural equation modeling. Both exploratory and confirmatory factor analyses verified that the 26 items map onto seven well-defined first-order latent constructs. The subscales exhibited moderate intercorrelations (ranging from r = .15 to .65), demonstrating that while they reflect interrelated facets of universal spirituality, they remain empirically distinguishable and non-redundant.

Convergent Validity

Convergent validity was evaluated by correlating SAIL subscales with established spiritual, psychological, and well-being scales. In the validation cohorts, the Transcendent Experiences and Spiritual Activities subscales demonstrated strong, statistically significant correlations with established spiritual measures, such as the Daily Spiritual Experience Scale (DSES; r values ranging from .60 to .75). The Connectedness with Nature subscale showed strong convergence with the Connectedness to Nature Scale (CNS; r > .65). Meaningfulness exhibited robust positive associations with Frankl-derived existential measures, such as the Purpose in Life Test (PIL; r > .60) and the Life Regard Index (LRI).

Discriminant Validity

A critical psychometric design objective of the SAIL was to avoid criterion overlap with general psychological well-being. Unlike previous measures (such as the FACIT-Sp or SWBS), the SAIL subscales demonstrated substantially lower correlations with measures of general positive affect, self-esteem (Rosenberg Self-Esteem Scale), and depressive symptomatology (measured via the CES-D or HADS). Specifically, correlations between SAIL subscales and psychological distress were consistently low to negligible (typically r = -.05 to -.25), proving that the instrument does not artificially measure emotional stability under the guise of spirituality.

Predictive and Known-Groups Validity

The SAIL demonstrated superior known-groups validity. In comparative analyses across the three validation cohorts, the cohort with an explicit spiritual interest scored significantly higher across all seven subscales (particularly Transcendent Experiences and Spiritual Activities, p < .001) compared to the general community and cancer survivor cohorts. Importantly, among cancer patients, the subscales of Meaningfulness, Trust, and Acceptance significantly predicted adaptive existential coping, coping flexibility, and quality-of-life adjustments over time, confirming its clinical predictive validity.

8. Reliability

The psychometric evaluation of the SAIL demonstrated high internal consistency, item-total correlation stability, and temporal test-retest reliability across multiple independent empirical trials.

Internal Consistency

Across the development and validation samples documented by de Jager Meezenbroek et al. (2012), Cronbach’s alpha coefficients demonstrated acceptable to excellent reliability across all seven subscales:

• Meaningfulness (3 items): α = .85 to .87
• Trust (4 items): α = .78 to .83
• Acceptance (4 items): α = .74 to .78
• Caring for Others (4 items): α = .76 to .81
• Connectedness with Nature (2 items): α = .85 to .89 (with high inter-item correlation, r > .74)
• Transcendent Experiences (5 items): α = .86 to .89
• Spiritual Activities (4 items): α = .81 to .86

The total scale reliability coefficient (composite alpha across all 26 items) consistently exceeded .90 (typically α = .91 to .93), demonstrating exceptional measurement precision across diverse respondent populations.

Test-Retest Stability

Temporal stability was established through longitudinal administrations over intervals ranging from 6 to 12 weeks among stable community and outpatient cohorts. Intra-class correlation coefficients (ICC) and Pearson correlation coefficients ranged between .72 and .88 across the seven subscales, indicating that the SAIL measures stable existential and spiritual traits rather than transient, state-dependent affective fluctuations.

9. Factor Analysis

The structural development of the SAIL relied on a multi-stage psychometric pipeline combining exploratory factor analysis (EFA) on an initial pool of over 70 items with subsequent confirmatory factor analysis (CFA) to identify the most parsimonious, robust model.

Exploratory Factor Analysis (EFA)

During initial scale development, maximum likelihood extraction with oblique (promax/oblimin) rotation was performed. Oblique rotation was selected because the underlying dimensions of universal spirituality were theoretically expected to correlate. The scree test, parallel analysis, and eigenvalues greater than 1.0 identified seven clearly interpretable factors matching the proposed theoretical model. Items exhibiting factor loadings < .40, communalities < .30, or significant cross-loadings (> .30 on secondary factors) were systematically eliminated, reducing the final inventory to 26 items.

Confirmatory Factor Analysis (CFA)

Confirmatory factor analysis was conducted on independent validation samples to test competing structural models: a unidimensional model, a three-factor model corresponding to the three relational axes, an independent seven-factor model, and a hierarchical second-order model. The seven-factor primary model, as well as a hierarchical model (seven first-order factors loading onto three higher-order factors: Connectedness with Self, Connectedness with Others/Nature, and Connectedness with Transcendent), showed superior fit to the empirical data compared to alternative specifications.

Standardized factor loadings for all 26 items on their designated latent factors were high and statistically significant (all p < .001), ranging from .62 to .91, indicating that each item serves as an effective indicator of its target construct.

10. Instrument / Measurement Tool

The SAIL is a standardized, self-administered questionnaire designed for adult respondents. Its operational parameters include:

• Instrument Name: Spiritual Attitude and Involvement List (SAIL)
• Item Count: 26 items
• Administration Time: Approximately 5 to 10 minutes
• Reading Level: 6th to 8th grade equivalent (accessible language devoid of theological or metaphysical jargon)
• Response Scales:
  • Items 1 through 18 (Endorsement / Intensity Anchor): Evaluated on a 6-point scale:
    • 1 = not at all
    • 2 = hardly at all
    • 3 = somewhat
    • 4 = to a reasonable degree
    • 5 = to a high degree
    • 6 = to a very high degree
  • Items 19 through 26 (Frequency Anchor): Evaluated on a 6-point scale:
    • 1 = never
    • 2 = seldom
    • 3 = sometimes
    • 4 = regularly
    • 5 = often
    • 6 = very often
• Subscale Item Composition:
  • Meaningfulness: Items 4, 12, 17
  • Trust: Items 1, 3, 9, 13
  • Acceptance: Items 6, 8, 11, 15
  • Caring for Others: Items 2, 7, 16, 18
  • Connectedness with Nature: Items 5, 14
  • Transcendent Experiences: Items 19, 20, 21, 23, 25
  • Spiritual Activities: Items 10, 22, 24, 26
• Scoring Protocol:
  • There are no reverse-scored items; all items are coded positively in the direction of higher spiritual involvement or attitude.
  • Subscale scores are calculated as the mean of the constituent items (ranging from 1.00 to 6.00). Retaining mean scores allows intuitive comparison across subscales despite differences in item count.
  • Second-order axis scores can be derived by calculating the mean of their constituent subscales: Connectedness with Self (mean of Meaningfulness, Trust, Acceptance), Connectedness with Others and Nature (mean of Caring for Others, Connectedness with Nature), and Connectedness with the Transcendent (mean of Transcendent Experiences, Spiritual Activities).
  • A total general spirituality score can be computed by calculating the overall mean of all 26 items (or the mean of the seven subscale scores).

11. Permissions & Fee and Test Year

The Spiritual Attitude and Involvement List (SAIL) was formally published in 2012 in the peer-reviewed journal Journal of Psychosocial Oncology. The scale was developed under the auspices of the Helen Dowling Institute, a non-profit academic center for psycho-oncology located in The Netherlands.

The authors have placed the instrument in the academic public domain for non-commercial research, academic, educational, and clinical applications. No royalty or user license fees are charged for non-profit research and clinical use. Researchers and clinicians wishing to utilize the SAIL are permitted to reproduce the scale items in non-commercial contexts provided proper citation of the primary publication (de Jager Meezenbroek et al., 2012) is maintained. Commercial entities, pharmaceutical clinical trials, or software developers seeking to incorporate the SAIL into proprietary commercial diagnostic tools should seek explicit permission from the corresponding authors and the publisher (Taylor & Francis).

12. References

• de Jager Meezenbroek, E. C., Garssen, B., van den Berg, M., Tuytel, G., van Dierendonck, D., Visser, A., & Schaufeli, W. B. (2012). Measuring spirituality as a universal human experience: Development of the Spiritual Attitude and Involvement List (SAIL). Journal of Psychosocial Oncology, 30(2), 141–167. https://doi.org/10.1080/07347332.2011.651258
• Frankl, V. E. (1985). Man’s Search for Meaning. Washington Square Press.
• Maslow, A. H. (1970). Religions, Values, and Peak-Experiences. Penguin Books.
• Underwood, L. G., & Teresi, J. A. (2002). The Daily Spiritual Experience Scale: Development, theoretical description, reliability, exploratory factor analysis, and preliminary construct validity using selected data in the General Social Survey. Annals of Behavioral Medicine, 24(1), 22–33. https://doi.org/10.1207/S15324796ABM2401_04
• Mayer, F. S., & Frantz, C. M. (2004). The connectedness to nature scale: A measure of individuals’ feeling in community with nature. Journal of Environmental Psychology, 24(4), 503–515. https://doi.org/10.1016/j.jenvp.2004.10.001
• van Dierendonck, D. (2004). The construct validity of Ryff’s Scales of Psychological Well-being and its extension with spiritual well-being. Personality and Individual Differences, 36(3), 629–643. https://doi.org/10.1016/S0191-8869(03)00122-3

13. Items of the Scale