Religious Belief Inventory

Abstract

The Religious Belief Inventory (RBI) is a multidimensional psychometric instrument developed by Ronald R. Lee in 1965 to quantify individual endorsement of distinct theological doctrines and belief systems within Christian and Western intellectual thought. Rooted in historical theological currents—specifically those intersecting within American Methodism and broader mainline Protestantism—the original RBI comprises 60 self-report items distributed across seven primary theoretical subscales (Fundamentalism, Orthodoxy, Humanism, Scientism, Puritanism, Pietism, and Liberalism), alongside four ad hoc exploratory items. Each subscale contains eight items evaluated on a 5-point Likert-type agreement continuum (scored 0 to 4, yielding subscale totals ranging from 0 to 32), with half of the items keyed in reverse to mitigate acquiescence bias.

Extensive psychometric investigations across diverse normative samples—including Garrett Theological Seminary students (N = 302), secular Northwestern University undergraduates (N = 111), and a secular agnostic/atheistic reference cohort (N = 26)—demonstrated marked heterogeneity in internal consistency across the seven original scales. Subsequent revision and empirical cross-validation identified a robust, four-scale composite model consisting of Fundamentalism, Orthodoxy, Humanism, and Puritanism. These consolidated dimensions exhibited satisfactory-to-high Guttman reproducibility coefficients (.88 to .94), moderate Kuder–Richardson reliability estimates (.50 to .72), and split-half reliability coefficients (.45 to .70), with Fundamentalism demonstrating the strongest internal consistency and criterion discriminability. Known-groups validity was evidenced by significant mean score differentiations between seminary ordinands, secular undergraduate cohorts, and non-believing populations.

Despite its historical utility in elucidating the nexus between doctrinal ideology, cognitive structure, and personality variables (e.g., intelligence, projective defense mechanisms, and social desirability), practical deployment of the RBI among contemporary lay populations requires circumspection due to complex theological terminology, obscure biblical references, and non-gender-neutral historical prose. Consequently, the instrument remains primarily oriented toward clerical assessment, seminary education research, and historical-psychometric inquiries within the psychology of religion.

Keywords

Religious Belief Inventory, theological measurement, fundamentalism, orthodoxy, humanism, puritanism, psychology of religion, psychometrics, Guttman reproducibility, Christian doctrine, Methodism, religious attitudes, personality and belief, Kuder-Richardson reliability

Authors

The Religious Belief Inventory was conceptualized, operationalized, and psychometrically standardized by Ronald R. Lee, Ph.D. The instrument constituted the empirical core of Lee’s doctoral dissertation, titled Theological belief as a dimension of personality, completed in 1965 within the Department of Psychology and the Joint Program in Religion and Psychology at Northwestern University in Evanston, Illinois, in close association with Garrett Theological Seminary (now known as the Garrett-Evangelical Theological Seminary).

Lee’s research was driven by the integration of clinical psychology, psychometric scaling, and historical theology. Across his academic and pastoral counseling career, Lee investigated how individual personality organization, psychological defenses, and cognitive capacities interface with the adoption and maintenance of specific religious ideologies. At the time of scale construction, inquiries regarding Lee’s research were coordinated through Northwestern University’s graduate psychology archives and the library repositories of Garrett Theological Seminary.

Purpose

The primary purpose of the Religious Belief Inventory is to provide an empirical, multidimensional assessment of doctrinal adherence across divergent intellectual traditions within Western religious philosophy. Historically, empirical research in the psychology of religion often suffered from unidimensional conceptualizations, treating religiosity as a monolithic continuum ranging from devout piety to secular skepticism. Such crude approximations failed to capture the vast structural, cognitive, and theological heterogeneity characterizing believers who occupy diametrically opposed positions within the same overarching faith tradition.

Lee designed the RBI on the fundamental premise that religious beliefs do not operate as isolated, haphazard cognitive assertions; rather, they “cluster in homogeneous patterns, as indicated by the existence of theological systems within the history of Christian thought” (Lee, 1965, p. 1). The instrument was intentionally engineered to achieve several programmatic objectives across empirical research and theological education:

• Mapping Multidimensional Doctrinal Positions: To systematically isolate, differentiate, and quantify agreement with distinct theological streams, distinguishing classical historical orthodoxy from militant fundamentalism, experiential pietism, socio-ethical liberalism, and secularized philosophical worldviews (humanism and scientism).
• Investigating Personality-Ideology Intersections: To serve as a standardized psychometric apparatus for testing empirical hypotheses regarding the relationship between theological convictions and fundamental personality structures, including cognitive flexibility, intellectual functioning, projective dynamics, and defensive ego functioning.
• Clerical and Seminary Assessment: To evaluate the ideological baseline and theological shifts of candidates entering ministerial training, tracking how formal academic divinity curricula alter or reinforce traditional dogmatic postures versus modern liberal-humanistic perspectives.
• Advancing Comparative Group Diagnostics: To enable robust behavioral comparisons between religious professionals, lay congregants, secular university students, and overt non-believers, establishing how theological affiliation moderates social attributions, moral reasoning, and interpersonal behaviors.

By moving beyond simplistic measures of church attendance, prayer frequency, or subjective religious enthusiasm, the RBI equips psychometricians and behavioral scientists with a structural diagnostic tool designed to evaluate the precise doctrinal scaffolding through which an individual interprets transcendence, human nature, epistemological authority, and moral imperative.

Psychological Construct

The overarching psychological construct quantified by the Religious Belief Inventory is theological doctrinal orientation—the extent of an individual’s cognitive endorsement of specific, systematic interpretations of divine reality, scripture, epistemology, and anthropology. Grounded in the historical evolution of Protestant theology (specifically the diverse ideological crosscurrents informing the Methodist tradition), the construct is structured into seven distinct dimensions, supplemented by exploratory indices:

1. Fundamentalism

The Fundamentalism dimension assesses adherence to an uncompromising, literalist, and dogmatic interpretation of Christian scripture and historical supernaturalism. In psychological terms, this construct reflects cognitive closed-mindedness regarding hermeneutics, a rejection of modernist biblical criticism, and an insistence on plenary verbal inspiration. It evaluates belief in the absolute historical and scientific inerrancy of biblical texts (e.g., miraculous historical events such as the sun standing still in Joshua 10:12–13), apocalyptic millenarianism, and the strict demarcation between absolute divine truth and worldly error. High scorers exhibit a defensive epistemic certainty that views cognitive ambiguity or theological compromise as apostasy.

2. Orthodoxy

The Orthodoxy dimension reflects commitment to historic, ecumenical Christian dogma as articulated across the classic creeds of antiquity (e.g., the Nicene and Apostles’ Creeds). Distinct from fundamentalism, orthodoxy focuses on core ontological and salvific doctrines: the Trinity, the true divinity and humanity of Jesus Christ, the doctrine of original sin, divine grace, and the bodily resurrection. Rather than demanding modern scientific inerrancy, orthodoxy emphasizes theological continuity with the historic Church. It measures a cognitive-affective identification with classic liturgical and doctrinal heritage without necessarily endorsing the militant anti-modernism characteristic of fundamentalism.

3. Humanism

The Humanism dimension measures the degree to which an individual locates ultimate value, ethical authority, and agency within human experience and worldly welfare rather than divine transcendent intervention. Rooted in secularized Enlightenment philosophy and modernist theological anthropology, high endorsement of humanism reflects a belief in the inherent goodness or educability of humanity, an emphasis on earthly social justice over celestial salvation, and the view that religious systems are human cultural artifacts designed to foster communal flourishing. The construct measures a radical shift in locus of control from external-theistic providence to autonomous human responsibility.

4. Scientism

Scientism quantifies an epistemological stance that elevates the empirical scientific method to the sole legitimate source of objective knowledge and truth. Within the matrix of religious ideation, this construct operates as a counter-theological, naturalistic worldview. It measures the explicit rejection of supernatural causality, metaphysical revelation, and mystical experiences, asserting that all physical and human phenomena are ultimately explicable through physical, biological, and sociological laws. In high scorers, religious doctrines are perceived as outdated pre-scientific mythologies.

5. Puritanism

The Puritanism dimension measures moral rigorism, asceticism, and an intensive concern with behavioral purity and divine judgment. Derived historically from the Reformed and early American Puritan ethos, this psychological construct assesses an individual’s preoccupation with human depravity, the constant temptation toward moral corruption, the absolute sovereignty of divine law, and the necessity of strict personal discipline. High scorers view human desires with suspicion, conceptualize the moral life as a rigorous warfare against temptation, and place high value on self-denial and ethical vigilance.

6. Pietism

The Pietism scale captures the experiential, affective, and devotional core of religious life, emphasizing the “religion of the heart” over dry scholastic doctrine or formal institutional ritual. Historically rooted in Continental Lutheran and Methodist revivals, this construct assesses the subjective reality of an intimate, personal relationship with Jesus Christ, the conscious experience of the Holy Spirit, daily devotional life, and personal transformation through conversion. It reflects an affective orientation wherein theological veracity is validated primarily through personal inner peace, spiritual warmth, and experiential communion with God.

7. Liberalism

The Liberalism scale measures theological modernism, characterized by an adaptive hermeneutic that seeks to harmonize religious faith with contemporary scientific knowledge, historical-critical biblical analysis, and progressive socio-political values. Psychologically, this construct reflects cognitive complexity, tolerance for ambiguity, and an openness to epistemic revision. Doctrinal formulations are viewed as historically situated, symbolic, and evolutionary rather than static or immutable. High scorers emphasize the universal fatherhood of God, the brotherhood of humanity, and the ethical imitation of Christ’s compassion over dogmatic conformity.

Theoretical Framework

The architecture of the Religious Belief Inventory is informed by a synthesis of historical theology, sociological typology, and mid-twentieth-century cognitive-personality psychology. Lee rejected the notion that personal faith could be accurately indexed by single-item self-ratings of devoutness, instead anchoring the RBI within the classical sociological typologies of Max Weber and Ernst Troeltsch, alongside H. Richard Niebuhr’s seminal conceptualization of Christian ideological diversity.

Weber and Troeltsch demonstrated that religious movements differentiate into institutional (church-type), radical-sectarian (sect-type), and interiorized (mystical) streams, each fostering vastly different cognitive, social, and moral postures. Within American Protestantism, these currents coalesced into competing theological systems. Methodism, which began as an evangelical, pietistic revival within the Anglican establishment, historically assimilated elements of Puritan moral discipline, classical Anglican orthodoxy, Continental pietism, and, in the late nineteenth and twentieth centuries, both conservative fundamentalism and theological liberalism. Lee posited that these historical movements persist within contemporary individual minds as coherent cognitive frameworks—or theological schemas—that structure how individuals perceive reality, divine authority, and selfhood.

From a psychological perspective, Lee integrated the cognitive-personality theories emerging from post-World War II research into ideological commitment. Foremost among these was Milton Rokeach’s theory of open and closed belief systems (The Open and Closed Mind, 1960). Rokeach posited that belief systems are organized along a continuum of dogmatism, defined by the extent to which an individual can receive, evaluate, and act upon relevant information on its intrinsic merits, unencumbered by irrelevant pressures arising from inner needs or authoritarian demands. Lee postulated that doctrinal positions such as Fundamentalism and Puritanism represent closed, rigid belief organizations characterized by high reliance on external institutional authority and intolerance for epistemic dissonance, whereas Liberalism and Humanism represent open, flexible organizations capable of assimilating conflicting evidence.

Furthermore, the RBI was developed concurrently with Gordon Allport’s distinction between intrinsic and extrinsic religious orientations. However, whereas Allport focused primarily on religious motivation (whether one “lives” or “uses” their religion), Lee argued that the cognitive content of belief itself constitutes an indispensable dimension of personality functioning. Lee hypothesized that particular theological clusters reflect specific underlying emotional dynamics, cognitive intelligence levels, and projective psychological defenses—positing that individuals actively select or reconstruct theological frameworks that resonate with their underlying character structures.

Validity

The construct, criterion, and discriminant validity of the Religious Belief Inventory were investigated across several targeted empirical studies utilizing known-groups methodologies and correlation matrices with validated psychological, intellectual, and personality instruments.

1. Known-Groups and Discriminant Validity

To establish whether the RBI scales could reliably differentiate populations with predictable ideological profiles, Lee administered the measure across three distinct socio-religious groups: Garrett Theological Seminary students (N = 302), secular undergraduate students at Northwestern University (N = 111), and a non-believing reference group composed of self-identified atheists and agnostics (N = 26). The empirical findings provided robust known-groups validity for the four core consolidated scales (Fundamentalism, Orthodoxy, Humanism, and Puritanism):

• Fundamentalism: The agnostic/atheistic sample scored drastically lower (M = 6.15, SD = 3.75) than both the seminary sample (M = 14.15, SD = 5.54) and the secular undergraduate sample (M = 15.15, SD = 7.01). The seminary cohort’s moderate mean reflected the theological diversity and moderate-to-liberal academic atmosphere of Garrett, while secular undergraduates demonstrated wider dispersion.
• Orthodoxy: As predicted, theological seminary students scored exceptionally high (M = 23.22, SD = 5.11), significantly exceeding secular undergraduates (M = 15.58, SD = 6.36) and the non-believing cohort (M = 9.00, SD = 3.37). This pronounced stratification confirmed that the Orthodoxy scale effectively indexed classic creedal affirmation.
• Humanism: Demonstrating powerful inverse discriminant validity, secular undergraduates (M = 18.14, SD = 4.16) and agnostic/atheistic individuals (M = 19.38, SD = 4.53) both scored significantly higher than the Garrett seminary students (M = 12.55, SD = 4.42), substantiating the scale’s sensitivity to naturalistic and human-centric worldviews.
• Puritanism: Seminary ordinands scored highest on Puritan moral rigorism (M = 12.62, SD = 3.84), followed by secular undergraduates (M = 10.59, SD = 4.62), with the non-believing sample scoring lowest (M = 8.93, SD = 4.28).

2. Convergent and Correlational Validity with Personality Constructs

Lee’s central investigative hypothesis was that theological positions would correlate systematically with intellectual ability and underlying personality organization. To evaluate this, Lee administered a comprehensive battery to the Garrett Theological Seminary sample, consisting of the Wechsler Adult Intelligence Scale (WAIS), the Rorschach Inkblot Test, and the Crowne–Marlowe Social Desirability Scale.

While some of Lee’s initial specific hypotheses regarding linear relationships between doctrinal adherence and WAIS full-scale IQ were not uniformly supported, the data revealed meaningful psychological differentiations. Fundamentalism and high Puritanism demonstrated significant associations with personality constriction, lower tolerance for ambiguity, and heightened needs for cognitive closure on Rorschach response variables. Conversely, high scores on Liberalism and Humanism correlated positively with openness to experience, intellectual striving, and lower social desirability response bias. Later research by Smith (1983) reinforced the RBI’s construct validity by demonstrating that high scores on Orthodoxy and Fundamentalism significantly predicted causal and sanctioning attributions to divine intervention, whereas Liberal and Humanist respondents systematically attributed personal outcomes to psychological and environmental actors.

Reliability

The psychometric evaluation of the original 60-item Religious Belief Inventory revealed notable disparities in scale reliability and item homogeneity. In his initial evaluation across the normative Garrett sample (N = 302), Lee discovered that only three of the original seven scales demonstrated acceptable internal consistency and unidimensional homogeneity: Fundamentalism, Orthodoxy, and Humanism. The remaining original scales (Scientism, Puritanism, Pietism, and Liberalism) suffered from psychometric instability, item ambivalence, and poor inter-item correlations.

Consequently, Lee undertook a formal psychometric revision of the problematic subscales. He re-operationalized items to enhance conceptual clarity and administered the revised instrument to a cohort of 111 entering Garrett Theological Seminary students. Unexpectedly, in this re-test cohort, only the revised Fundamentalism, Orthodoxy, and the newly revised Puritanism scales exhibited adequate psychometric rigor, while the revised Humanism items demonstrated degraded reliability compared to their original formulation. Addressing this anomaly, Lee synthesized what psychometricians designate as the Combined Religious Belief Inventory, which incorporates the revised versions of the Fundamentalism, Orthodoxy, and Puritanism scales paired with the original, unrevised Humanism scale.

The psychometric parameters for the four validated scales of the Combined RBI are summarized below:

• Guttman Reproducibility Coefficients: Demonstrating high-to-exceptional scale homogeneity (unidimensional scalogram property), the coefficients of reproducibility exceeded conventional psychometric thresholds:
  • Puritanism Scale: .94
  • Fundamentalism Scale: .93
  • Orthodoxy Scale: .88
  • Humanism Scale: .88
• Kuder–Richardson Reliability Coefficients (KR-20 / Internal Consistency):
  • Fundamentalism Scale: .72
  • Orthodoxy Scale: .69
  • Puritanism Scale: .62
  • Humanism Scale: .50
• Split-Half Reliability Coefficients:
  • Fundamentalism Scale: .70
  • Puritanism Scale: .60
  • Orthodoxy Scale: .54
  • Humanism Scale: .45

Across all psychometric evaluations, the Fundamentalism Scale consistently emerged as the most structurally sound, homogeneous, and reliable component of the inventory, followed by Puritanism and Orthodoxy. Lee concluded that investigators utilizing the RBI should rely primarily on these four validated scales, as the Scientism, Pietism, and Liberalism dimensions failed to achieve sufficient psychometric reproducibility to justify independent diagnostic deployment.

Factor Analysis

The structural dimensionality of the Religious Belief Inventory was analyzed primarily through Guttman scalogram analysis and classical item-total correlation techniques common to mid-twentieth-century test construction, followed by exploratory factor evaluations in subsequent literature. Lee designed each scale to operate as a quasi-Guttman continuum, wherein an endorsement of more extreme theological propositions (e.g., total biblical inerrancy in the Fundamentalism scale) would logically subsume endorsement of more moderate doctrinal positions.

The Guttman reproducibility coefficients obtained for the four retained scales (.88 to .94) confirmed that these items formed a highly homogeneous hierarchy of theological acceptance. Specifically, the Puritanism (.94) and Fundamentalism (.93) dimensions demonstrated strong structural unidimensionality, indicating that response error was minimal and that a single latent trait accounted for the variance across the eight items in each respective scale.

Subsequent psychometric examinations (such as those reviewed by Gorsuch & McFarland, 1972) subjected multidimensional religious belief inventories, including the RBI, to exploratory factor analysis (EFA). When all 56 domain items were factored concurrently across heterogeneous samples, three dominant higher-order latent factors consistently emerged:

1. Traditional Orthodoxy / Supernaturalism: Characterized by high positive loadings from the Fundamentalism and Orthodoxy subscales and moderate loadings from Puritanism. This factor captures cognitive adherence to traditional, supernatural Christian doctrine and moral absolutes.
2. Secular Rationalism / Humanistic Immanence: Characterized by high positive loadings from the Humanism and Scientism subscales, paired with strong negative cross-loadings on Fundamentalism and Orthodoxy. This dimension indexes an empirical, naturalistic orientation that rejects metaphysical causality.
3. Experiential Devotion / Moral Restraint: Characterized by primary loadings from the Pietism and Puritanism subscales, reflecting personal devotional affect, behavioral vigilance, and interiorized commitment to moral purity.

These factorial findings confirmed that while the original seven-scale conceptual model was theoretically distinct from a theological history perspective, psychometrically the variance is largely accounted for by a broader orthogonal structure contrasting traditional supernaturalism against secular naturalism, crossed with an affective-moral discipline vector.

Instrument / Measurement Tool

The technical parameters, administrative procedures, and operational characteristics of the Religious Belief Inventory are outlined below:

• Instrument Type: Standardized, multidimensional, self-administered cognitive-attitudinal inventory.
• Total Item Count: 60 items total (56 scale-assigned items divided evenly into 7 subscales of 8 items each, plus 4 unassigned ad hoc exploratory items). In the validated “Combined Version,” researchers primarily score the 32 items comprising the four psychometrically sound subscales (Fundamentalism, Orthodoxy, Humanism, Puritanism).
• Response Continuum: 5-point Likert-type agreement scale ranging from “Strongly Disagree” to “Strongly Agree”.
• Administration Format: Paper-and-pencil or supervised digital administration; self-administered individually or in group settings.
• Administration Time: Approximately 25 to 35 minutes for the full 60-item battery.
• Target Populations: Primarily standardized on theological seminary students, clergy, and university undergraduates. Extreme caution is indicated when administering to lay congregants.
• Scoring Architecture:
  • Each item is scored on a numeric continuum from 0 to 4 (or 1 to 5, historically normalized to 0–4 for scale tabulation).
  • Reverse Scoring: Exactly four of the eight items on each individual scale are negatively keyed (reverse scored) to control for acquiescence and response-set bias. Reverse items are inverted by subtracting the raw response from 4 (where 0 becomes 4, 1 becomes 3, 2 remains 2, 3 becomes 1, and 4 becomes 0).
  • Subscale Total: Calculated by summing the scores of all eight scale items following reverse-score adjustments.
  • Subscale Score Range: Each subscale yields a possible continuous score ranging from 0 to 32, where higher scores signify greater doctrinal endorsement of that specific theological system.
• Practical Caveats & Administrative Limitations:
  • Syntactic and Lexical Sophistication: The inventory employs complex, academically dense theological and philosophical vocabulary (e.g., “fallible,” “natural procreation,” “creedal affirmation”). These terms frequently generate cognitive fatigue and miscomprehension when administered to lay congregants or populations lacking formal theological education.
  • Negative Wording Confusion: The inclusion of four reverse-scored, negatively framed propositions per scale frequently causes cognitive interference and double-negative confusion among non-academic respondents.
  • Obscure Scriptural Arcana: Certain scale items rely upon specific, highly obscure biblical historical references. For example, item 47 states: “When Joshua commanded the sun to stand still, it did so.” During empirical field testing with lay church members, respondents frequently halted testing to inquire whether the event was actually recorded in scripture, noting they would score “Strongly Agree” if biblical and “Strongly Disagree” if not—introducing significant measurement error based on biblical literacy rather than theological stance.
  • Non-Gender-Neutral Historical Phrasing: Written in the mid-1960s, the instrument utilizes archaic masculine generics throughout (e.g., “man” instead of “humanity” or “people,” such as in item 43: “People are not sinful, merely foolish”). Modern administrations require editorial modernization to maintain face validity.

Permissions & Fee and Test Year

The Religious Belief Inventory was formally constructed and copyrighted as an academic measurement tool in 1965 as part of Ronald R. Lee’s doctoral dissertation at Northwestern University. Because the instrument was developed under academic auspices and published within a university doctoral repository rather than through a commercial psychological test publisher (e.g., Pearson, PAR, or Western Psychological Services), there are no commercial purchase fees associated with its non-profit, academic utilization.

The complete dissertation, inclusive of item text, factor tables, and scoring keys, is cataloged in the institutional archives of Northwestern University and accessible through ProQuest Dissertations & Theses Global (UMI Publication Number: 6602724). Psychometricians, behavioral researchers, and seminary faculty are permitted to utilize the scale under academic fair use provisions for empirical and non-commercial educational research, provided that formal scholarly citation is credited to Lee (1965). Any intended commercial exploitation, standardized software integration, or widespread digital dissemination requires explicit archival clearance from Northwestern University’s copyright administration.

References

• Allport, G. W., & Ross, J. M. (1967). Personal religious orientation and prejudice. Journal of Personality and Social Psychology, 5(4), 432–443. https://doi.org/10.1037/h0021212
• Gorsuch, R. L., & McFarland, S. G. (1972). Single vs. multiple item scales for measuring religious values. Journal for the Scientific Study of Religion, 11(1), 53–64. https://doi.org/10.2307/1384381
• Lee, R. R. (1965). Theological belief as a dimension of personality (Doctoral dissertation, Northwestern University). ProQuest Dissertations Publishing, Publication No. 6602724.
• Malony, H. N. (Ed.). (1977). Current perspectives in the psychology of religion. Wm. B. Eerdmans Publishing Company.
• Niebuhr, H. R. (1951). Christ and culture. Harper & Row.
• Rokeach, M. (1960). The open and closed mind: Investigations into the nature of belief systems and personality systems. Basic Books.
• Smith, C. S. (1983). Sanctioning and causal attributions to God: A function of theological position and actors’ characteristics (Doctoral dissertation, Graduate School of Psychology, Fuller Theological Seminary). ProQuest Dissertations Publishing.
• Troeltsch, E. (1931). The social teaching of the Christian churches (O. Wyon, Trans.; Vols. 1–2). The Macmillan Company.

Items of the Scale