The Christian Orthodoxy Scale

Abstract

The Christian Orthodoxy (CO) Scale, developed by J. Timothy Fullerton and Bruce Eunsberger in 1982, is a psychometric instrument designed to measure individual acceptance of central, orthodox theological tenets fundamental to traditional Christianity. Grounded historically in the ecumenical affirmations of the Apostles’ Creed and the Nicene Creed, the scale captures an individual’s cognitive endorsement of bedrock Christian doctrines across diverse denominations, including Catholicism, Eastern Orthodoxy, and mainline or evangelical Protestantism. The standard full-length scale comprises 24 self-report items—balanced symmetrically with 12 positively keyed statements and 12 negatively keyed statements to mitigate acquiescence response bias—evaluated along a 7-point Likert-type agreement continuum ranging from -3 (Strongly Disagree) to +3 (Strongly Agree), with an explicit neutral midpoint (0). A psychometrically validated 6-item short form was subsequently established by Hunsberger in 1989. Psychometrically, the CO Scale demonstrates exceptional internal consistency, with Cronbach’s alpha coefficients routinely documented between .97 and .98, and mean inter-item correlations ranging between .57 and .70 across heterogeneous normative cohorts totaling over 2,200 participants. Exploratory and confirmatory factor analyses robustly sustain a strictly unidimensional factor structure, demonstrating that diverse doctrinal statements (e.g., the Trinity, the virgin birth, Christ’s resurrection, divine creation, biblical inspiration, and efficacy of prayer) cohere onto a single, dominant cognitive factor. Criterion, convergent, and known-groups validity evidence shows profound positive associations with public religious attendance (r = .62), private devotional prayer (r = .70), and scriptural trust (r = .77), alongside robust discrimination between religious apostates (M = 61.8) and persistent religious adherents (M > 111.0). This article provides a comprehensive psychometric review of the CO Scale, encompassing its theoretical foundations, structural mechanics, normative values, scoring paradigms, and research utility.

Keywords

Christian Orthodoxy Scale, religious beliefs, psychometrics, Apostles’ Creed, Nicene Creed, unidimensionality, religious psychology, apostasy, theological orthodoxy, Bruce Hunsberger, scale validation

Authors

The Christian Orthodoxy Scale was constructed by J. Timothy Fullerton and Bruce Hunsberger. Initial development and validation studies were carried out through the Department of Psychology at the University of Waterloo and Wilfrid Laurier University in Waterloo, Ontario, Canada.

Bruce Hunsberger, Ph.D. (1944–2003) was an internationally distinguished psychologist of religion, Professor of Psychology, and long-time Department Chair at Wilfrid Laurier University. A recipient of the William James Award from Division 36 (Society for the Psychology of Religion and Spirituality) of the American Psychological Association (APA), Dr. Hunsberger published landmark research examining religious socialization, apostasy, fundamentalism, prejudice, and the cognitive complexity of religious thinking. J. Timothy Fullerton, Ph.D. collaborated extensively with Hunsberger on early empirical assessments of religious socialization, church switching, and belief stability during emerging adulthood.

Purpose

The primary psychometric objective of the Christian Orthodoxy Scale is to quantify the cognitive-ideational dimension of religious commitment within a Christian frame of reference. Prior to the development of the CO Scale, existing psychometric inventories measuring religiosity were frequently compromised by multidimensional confounding, denominational idiosyncrasy, or conflation between religious *belief* (ideology) and religious *style* (such as intrinsic/extrinsic orientation or rigid fundamentalism). Fullerton and Hunsberger (1982) sought to engineer a psychometrically pure, strictly unidimensional instrument capable of evaluating adherence to the shared theological core that historically transcends specific denominational cleavages.

The theoretical rationale rests on historical ecumenism: despite centuries of theological disputes regarding ecclesiastical authority, sacraments, liturgical aesthetics, and soteriological nuances, a core baseline of doctrinal consensus unites historical Christianity. These tenets—formalized during the early ecumenical councils and synthesized in the Apostles’ and Nicene Creeds—represent the “bedrock” boundary markers of Christian identity. The CO Scale addresses the vital research need to isolate this core content of belief from surrounding psychosocial factors.

In empirical and applied research settings, the CO Scale fulfills several crucial functions:

• Differentiation between Religious Content and Religious Structure: In social psychology and the psychology of religion, researchers must distinguish *what* a person believes from *how* they hold those beliefs. The CO Scale quantifies the specific cognitive content of orthodox Christian ideology, allowing researchers to study how this content interacts with constructs such as Right-Wing Authoritarianism (RWA), Religious Fundamentalism (RF), and integrative complexity.
• Longitudinal Investigation of Religious Socialization and Apostasy: The scale reliably tracks longitudinal trajectories of faith retention, denominational switching, religious deconversion, and secular apostasy during key developmental windows, such as the transition from adolescence to tertiary education.
• Clinical and Pastoral Assessment: Although primarily an empirical research instrument, the scale offers pastoral counselors, chaplains, and clinical psychologists a standardized metric to evaluate spiritual struggle, theological dissonance, and shifts in personal faith identity during major life stressors or identity transitions.

Psychological Construct

The construct assessed by the Christian Orthodoxy Scale is the cognitive-affective acceptance of fundamental, classical Christian theological affirmations. Unlike behavioral indices that assess ritual frequency (e.g., church attendance, fasting, scripture study) or functional constructs that evaluate religious motivation (e.g., Gordon Allport’s intrinsic versus extrinsic orientations), the CO construct focuses on subjective doctrinal assent.

Although the scale operates empirically as a strictly unidimensional instrument, its 24 items systematically sample across multiple interconnected theological sub-domains that define classical Christian orthodoxy:

• The Nature of the Godhead and Trinity: Acceptance of monotheism expressed through the triune nature of God (Father, Son, and Holy Spirit), and rejection of secular or non-theistic models that depict God as an obsolete superstition (e.g., Item 1: “God exists as Father, Son, and Holy Spirit”; Item 9: “The concept of God is an old superstition…”).
• The Divinity and Incarnation of Jesus Christ: Affirmation that Jesus of Nazareth was uniquely divine, incarnate through the virgin birth, rather than solely a historical, mortal moral philosopher (e.g., Item 3: “Jesus Christ was the divine Son of God”; Item 7: “Jesus was born of a virgin”; Item 13: “Jesus Christ may have been a great ethical teacher… But he was not the divine Son of God”).
• Soteriology and the Atonement: The conviction that human beings are fundamentally reconciled to God, pardoned of sin, and redeemed through the sacrificial crucifixion and bodily resurrection of Jesus Christ (e.g., Item 15: “Through the life, death, and resurrection of Jesus, God provided a way for the forgiveness of man’s sins”; Item 22: “Jesus’ death on the cross, if it actually occurred, did nothing in and of itself to save Mankind”).
• The Resurrection and Eschatology: Assent to the historical, bodily resurrection of Jesus Christ as proof of His Messiahship, belief in His promised physical return (parousia), and the immortality of the human soul (e.g., Item 17: “Jesus was crucified, died, and was buried but on the third day He arose from the dead”; Item 10: “Christ will return to the earth someday”; Item 18: “In all likelihood there is no such things as a God-given immortal soul in Man…”).
• Anthropology and Special Creation: The doctrine that humanity was intentionally created in the image of God (imago Dei) rather than existing as merely an unintended byproduct of undirected evolutionary mechanisms (e.g., Item 2: “Man is not a special creature made in the image of God; he is simply a recent development in the process of animal evolution”; Item 14: “God made man of dust in His own image…”).
• Divine Revelation, Providence, and Miracles: The epistemological stance that the Holy Bible is divinely inspired, that God intervenes directly in physical and historical realities via miracles, and that God remains providently attentive to personal prayers (e.g., Item 4: “The Bible is the word of God given to guide man…”; Item 5: “Those who feel that God answers prayers are just deceiving themselves”; Item 11: “Most of the religions in the world have miracle stories… but there is no reason to believe any of them are true…”; Item 12: “God hears all of our prayers”).

Crucially, Fullerton and Hunsberger demonstrated that these distinct theological domains do not generate discrete behavioral factors; rather, in the psychology of believers, they function as a tightly woven theological tapestry. Adherence to one foundational proposition strongly predicts adherence to the others, forming a coherent belief schema.

Theoretical Framework

The theoretical underpinning of the Christian Orthodoxy Scale is situated within cognitive and multidimensional models of religiosity, notably influenced by the sociological frameworks of Charles Glock and Rodney Stark (1965) and the cognitive psychological traditions of social attitude measurement.

Glock and Stark’s Multidimensional Model

Glock and Stark posited that religiosity cannot be treated as a monolithic variable; rather, it manifests across at least five distinct dimensions:

1. The Ideological Dimension (Belief): Expectations that religious adherents will hold certain cognitive convictions and theological truths.
2. The Intellectual Dimension (Knowledge): The expectation that religious persons will possess an informational awareness of scripture, history, and theology.
3. The Ritualistic Dimension (Practice): Execution of formal rites, attendance at worship services, and participation in communal practices.
4. The Experiential Dimension (Feeling): Subjective emotional states, mystical experiences, or perceived encounters with the transcendent.
5. The Consequential Dimension (Effects): The pragmatic secular outcomes of religious belief on health, morality, relationships, and societal engagement.

Fullerton and Hunsberger deliberately focused the CO Scale on Glock and Stark’s ideological dimension. They argued that many previous psychometric inventories conflated belief with ritual behavior, emotional engagement, or institutional loyalty. By isolating the cognitive dimension, the CO Scale allows researchers to treat theological belief as an independent variable and evaluate how doctrinal assent causally relates to religious behaviors, emotional experiences, and psychological outcomes.

Differentiating Content from Cognitive Style

A vital theoretical development involving the CO Scale was advanced by Bruce Hunsberger in collaboration with Bob Altemeyer and other researchers. In social psychology, an ongoing debate centered on whether intense religious adherence inevitably fostered racial prejudice, authoritarianism, and cognitive rigidity. Earlier measures of “religious fundamentalism” often blurred the boundary between orthodox theological tenets and closed-minded, defensive cognitive styles.

By establishing the CO Scale as a measure of theological *content*, Hunsberger and colleagues (e.g., Altemeyer & Hunsberger, 1992; Kirkpatrick, 1993) demonstrated that Christian Orthodoxy represents what one believes, whereas Religious Fundamentalism measures the *dogmatic, militant certainty* with which one holds those beliefs. While the two scales are substantially correlated in practice, they show different patterns of association with dependent variables: religious fundamentalism typically correlates positively with social prejudice, ethnocentrism, and low integrative complexity, whereas orthodox Christian belief itself often correlates weakly, negatively, or insignificantly with racial and ethnic prejudice once fundamentalism and authoritarianism are statistically controlled.

Validity

The Christian Orthodoxy Scale possesses extensive, multi-method psychometric validity documented across several decades of empirical administration.

Construct and Known-Groups Validity

Known-groups validation provides exceptionally compelling evidence for the construct validity of the CO Scale. Fullerton and Hunsberger (1982) examined scale performance across a diverse validation cohort of 2,297 individuals drawn from Canadian high schools, universities, and community samples, segmented into distinct denominational and ideological categories:

• Apostates: Individuals raised in a religious tradition who subsequently abandoned religious faith displayed a mean CO score of 61.8 (SD = 31.9), demonstrating profound rejection of orthodox doctrines.
• Denominational Switchers: Individuals who migrated from one Christian denomination to another retained high doctrinal orthodoxy, exhibiting a mean score of 130.4 (SD = 30.6).
• Active Believers and General Cohorts: Believer groups, including urban high school students, rural students, Canadian university students, and their parents, consistently produced mean scores between 111.9 and 130.4.

The statistical divergence between religious dropouts (apostates) and believers yielded an effect size exceeding d = 2.0, confirming that the scale differentiates precisely between individuals who have disaffiliated from religious belief systems and those who remain doctrinally committed.

Convergent and Criterion Validity

The CO Scale correlates strongly with external, overt markers of religious commitment. Fullerton and Hunsberger (1982) established significant bivariate correlations between the CO Scale and several behavioral and cognitive criteria:

• Frequency of Personal Prayer: r = .70 (p < .001), indicating that doctrinal assent is tightly linked to personal devotional communication.
• Trust in the Bible’s Guidance: r = .77 (p < .001), showing deep concordance between creedal agreement and epistemic authority granted to scripture.
• Composite Religious Behavior: r = .75 (p < .001), a structural index aggregating diverse behavioral activities.
• Trust in Church Guidance: r = .68 (p < .001).
• Public Religious Service Attendance: r = .62 (p < .001).
• Scriptural and Devotional Reading: r = .57 (p < .001).

Discriminant Validity

Subsequent psychometric investigations have established discriminant validity between the CO Scale and non-creedal psychosocial constructs. Kirkpatrick (1993) demonstrated that while Christian Orthodoxy, Religious Fundamentalism, and Intrinsic Religious Orientation share variance, the CO Scale uniquely measures adherence to specific creedal propositions. Similarly, Pancer et al. (1995) and Pratt et al. (1992) revealed that high scores on Christian Orthodoxy do not uniformly depress cognitive complexity across non-religious domains, demonstrating that theological assent does not reflect a generalized cognitive deficit.

Reliability

The Christian Orthodoxy Scale exhibits outstanding internal consistency across diverse empirical populations.

Internal Consistency

In the seminal 1982 validation study by Fullerton and Hunsberger across ten independent normative subsamples (including high school students, university undergraduates, parents, apostates, and an Australian cross-cultural replication sample), the Cronbach’s alpha coefficients of the 24-item scale were systematically documented at .98 across nine groups, and .97 in the tenth group. Such values indicate exceptional homogeneity among scale items.

Furthermore, the mean inter-item correlation coefficients across these diverse validation cohorts ranged from .57 to .70. This range reflects substantial internal coherence without redundancy, confirming that the 24 items represent a unified construct.

Reliability of the 6-Item Short Form

To reduce survey fatigue and facilitate integration into large-scale multi-scale batteries, Hunsberger (1989) developed an abbreviated 6-item short form (CO-Short). Despite reducing the scale length by 75%, the 6-item short form retained exceptional reliability, yielding Cronbach’s alpha coefficients consistently between .93 and .95 in validation cohorts. The bivariate correlation between the full 24-item scale and the 6-item short form routinely equals or exceeds r = .97, illustrating near-perfect measurement equivalence.

Sex Differences and Demographic Invariance

Across the normative groups reported by Fullerton and Hunsberger, female respondents scored higher than male respondents across 7 of the 10 believer groups (excluding the apostate sample), consistent with broader empirical trends observed in the sociology of religion regarding female religious commitment. Internal consistency metrics remained equally robust (.97 to .98) across both male and female subsamples, indicating that the scale items function invariantly across sexes.

Factor Analysis

A key contribution of Fullerton and Hunsberger’s (1982) investigation was resolving the empirical question of whether religious belief constitutes a multidimensional structure requiring distinct subscales, or a single overarching cognitive construct.

Exploratory Factor Analytic Findings

The authors subjected the 24 items to Exploratory Factor Analysis (EFA) using principal component and principal axis extraction methods across their multi-thousand participant database. Inspection of the resulting eigenvalues and scree plots revealed a prominent, solitary unrotated factor. In every analyzed sample:

• The first unrotated principal factor accounted for the vast majority of the common item variance (frequently between 65% and 75% of total variance).
• Subsequent eigenvalues dropped sharply below 1.0 or leveled off asymptotically in scree tests, demonstrating no evidence of secondary substantive factors.
• All 24 items exhibited high factor loadings on this single latent dimension, almost uniformly loading above .60, with many exceeding .80.

These empirical findings confirmed that while theological propositions can be conceptually subdivided into distinct scholastic categories (e.g., Christology, Pneumatology, Hamartiology, Bibliology), psychological adherence to these tenets operates in a strongly unified manner. Individuals do not selectively endorse the virgin birth while discarding the resurrection or the Trinity; instead, belief in historic Christian tenets forms an integrated cognitive network.

Confirmatory Structural Invariance

Subsequent psychometric examinations using Confirmatory Factor Analysis (CFA) across cross-national and cross-denominational populations have continually supported the single-factor specification. Model fit indices for the unidimensional structure consistently yield Comparative Fit Indices (CFI) and Tucker-Lewis Indices (TLI) exceeding .90, validating the construct’s structural integrity across Catholic, mainline Protestant, and evangelical Protestant samples.

Instrument / Measurement Tool

• Test Type: Standardized self-report cognitive attitude questionnaire / ideational survey.
• Target Population: Adolescents and adults (typically ages 14 and older) possessing basic literacy skills. Applicable across clinical, academic, cross-cultural, and pastoral contexts.
• Administration Time: Approximately 10 to 15 minutes for the full 24-item version; approximately 2 to 3 minutes for the 6-item short form.
• Item Count: 24 total items in the standard comprehensive scale; 6 items in the abbreviated short form.
• Item Polarity: Perfectly balanced; 12 items are positively worded (assent indicates orthodox Christian belief) and 12 items are negatively worded (assent indicates unorthodox or skeptical belief).
• Response Scale: 7-point Likert-type scale with an explicit zero midpoint:
  • -3: Strongly disagree
  • -2: Moderately disagree
  • -1: Slightly disagree
  • 0: Exactly and precisely neutral
  • +1: Slightly agree
  • +2: Moderately agree
  • +3: Strongly agree

  (Note: Fullerton and Hunsberger also permitted an expanded 9-point format from -4 [Very strongly disagree] to +4 [Very strongly agree], which demonstrates equivalent psychometric properties).

• Scoring Algorithm and Transformation:
  1. Handling Missing Data: Fullerton and Hunsberger recommend discarding a respondent’s protocol if 10 or more items are omitted. Individual omitted responses on retained protocols are scored as 0 (neutral).
  2. Rescaling to Positive Integers: Raw responses are rescaled to a 1–7 scale by adding a constant of 4:
     
     -3 becomes 1;
     
     -2 becomes 2;
     
     -1 becomes 3;
     
     0 (or missing) becomes 4;
     
     +1 becomes 5;
     
     +2 becomes 6;
     
     +3 becomes 7.
  3. Reverse Keying: Reverse-code all 12 negatively worded items so that higher scores consistently reflect higher orthodoxy. On the 1–7 rescaled metric, the reversed score equals: Reversed Score = 8 - Rescaled Score (e.g., a rescaled score of 7 becomes 1; a rescaled score of 1 becomes 7). The 12 negatively worded items requiring reverse scoring are:
     
     Items 2, 5, 6, 8, 9, 11, 13, 16, 18, 19, 22, and 23.
  4. Total Score Calculation: The grand Christian Orthodoxy (CO) score is computed by summing the rescaled scores across all 24 items.
     
     Score Range: Minimum possible score = 24 (extreme theological unorthodoxy / thorough secular skepticism); Maximum possible score = 168 (absolute, unreserved theological orthodoxy). A score of 96 represents exact theological neutrality.
• Interpretation Benchmarks (Based on Fullerton & Hunsberger Norms):
  • 24 – 75: Strongly Unorthodox / Apostate / Non-Believing Profile (typical of individuals who have rejected institutional religious doctrine; mean apostate score = 61.8).
  • 76 – 105: Moderate / Ambivalent / Skeptical Posture (characterized by theological uncertainty, agnostic ambivalence, or highly non-traditional interpretations).
  • 106 – 140: Conventional Orthodox Christian Believer Profile (normative range for broad Catholic and mainline Protestant churchgoers; general believer means fall between 111.9 and 130.4).
  • 141 – 168: Highly Devout / Traditionalist / Conservative Christian Profile (frequent among active evangelical, charismatic, or traditionalist church members).

Permissions & Fee and Test Year

The full 24-item Christian Orthodoxy Scale was published in 1982 in the Journal for the Scientific Study of Religion, followed by the 6-item short form in 1989. The scale is copyrighted by the Society for the Scientific Study of Religion (SSSR) and the authors.

The scale was placed into the academic public domain for scientific, non-commercial research, academic investigations, educational demonstrations, and clinical research purposes. No licensing fees or royalties are required for non-profit academic scholarship, provided proper bibliographic attribution is given to Fullerton and Hunsberger (1982) and Hunsberger (1989). Commercial applications, integration into proprietary digital platforms, or distribution in for-profit assessment environments require formal copyright clearance from the publisher (Wiley-Blackwell on behalf of the SSSR).

References

• Altemeyer, B., & Hunsberger, B. (1992). Authoritarianism, religious fundamentalism, quest, and prejudice. The International Journal for the Psychology of Religion, 2(2), 113–133. https://doi.org/10.1207/s15327582ijpr0202_5
• Fullerton, J. T., & Hunsberger, B. (1982). A unidimensional measure of Christian orthodoxy. Journal for the Scientific Study of Religion, 21(4), 317–326. https://doi.org/10.2307/1385521
• Glock, C. Y., & Stark, R. (1965). Religion and society in tension. Rand McNally.
• Hunsberger, B. (1989). A short version of the Christian Orthodoxy Scale. Journal for the Scientific Study of Religion, 28(3), 360–365. https://doi.org/10.2307/1386745
• Hunsberger, B., Pratt, M., & Pancer, S. M. (1994). Religious fundamentalism and integrative complexity of thought: A relationship for existential content only? Journal for the Scientific Study of Religion, 33(4), 335–346. https://doi.org/10.2307/1386493
• Kirkpatrick, L. A. (1993). Fundamentalism, Christian orthodoxy, and intrinsic religious orientation as predictors of discriminatory attitudes. Journal for the Scientific Study of Religion, 32(3), 256–268. https://doi.org/10.2307/1386664
• Pancer, S. M., Jackson, L. M., Hunsberger, B., Pratt, M. W., & Lea, J. (1995). Religious orthodoxy and the complexity of thought about religious and nonreligious issues. Journal of Personality, 63(2), 213–232. https://doi.org/10.1111/j.1467-6494.1995.tb00808.x
• Pratt, M. W., Hunsberger, B., Pancer, S. M., & Roth, D. (1992). Reflections on religion: Aging, belief orthodoxy, and interpersonal conflict in the complexity of adult thinking about religious issues. Journal for the Scientific Study of Religion, 31(4), 514–522. https://doi.org/10.2307/1386859

13. Items of the Scale (Questionnaire)