Duke University Religion Index (DUREL)

Abstract

The Duke University Religion Index (DUREL) is a widely used, five-item self-report measure developed to assess three crucial dimensions of religious commitment for use primarily in health research and epidemiological studies. It provides a concise yet multidimensional assessment of religious life, distinguishing between public practice, private practice, and subjective religious experience or belief. The brevity and established psychometric properties of the DUREL make it an ideal tool for large-scale surveys where respondent time is limited.

Keywords

Duke University Religion Index, DUREL, Religiosity, Organizational Religious Activity, Non-organizational Religious Activity, Intrinsic Religiosity, Health psychology, Spiritual assessment, Psychological scale.

Authors

P. C. Hill, R. W. Hood, Jr., Harold G. Koenig, Arndt Büssing.

Purpose

The primary purpose of the DUREL is to provide a brief, standardized, and reliable instrument capable of measuring the key aspects of religious commitment. Developed specifically for application in clinical and epidemiological studies, the scale allows researchers to efficiently examine the relationship between religious factors and various health outcomes, mental health status, and coping mechanisms.

Its design emphasizes practicality, ensuring that the measure can be easily incorporated into larger research protocols without causing undue burden on participants while still capturing the complexity of religious involvement across different faith traditions (e.g., accommodating references to Church/Mosque and Bible/Koran).

Construct

The DUREL measures religiosity as a multidimensional construct comprising three distinct components, which are assessed using the five items:

• Organizational Religious Activity (ORA): Measured by one item (Item 1), this assesses participation in public, communal religious services or meetings (e.g., attending church or mosque).
• Non-organizational Religious Activity (NORA): Measured by one item (Item 2), this assesses private religious practices, such as prayer, meditation, or private religious study.
• Intrinsic Religiosity (IR): Measured by three items (Items 3, 4, and 5), this assesses the subjective, internal experience of faith, including the extent to which religious beliefs motivate life choices and constitute a core identity. This dimension reflects the degree to which religion is internalized and serves as a fundamental approach to life.

Validity

The DUREL has demonstrated strong construct and criterion validity across numerous studies and diverse cultural contexts. Its three-factor structure consistently aligns with established theoretical models of religious involvement (e.g., Allport’s distinction between intrinsic and extrinsic orientation, and various behavioral measures).

Cross-cultural validation studies, such as the validation of the Farsi version on Muslim populations, have confirmed that the underlying structure and meaning of the three dimensions—ORA, NORA, and IR—are maintained, suggesting the scale is appropriate for use globally in different religious contexts. Furthermore, the DUREL scores typically correlate meaningfully with measures of spiritual well-being and health outcomes, supporting its utility as a reliable predictor in medical research.

Reliability

The scale exhibits acceptable to strong reliability, particularly for the three-item Intrinsic Religiosity subscale. Studies examining the psychometric properties of the DUREL often report high internal consistency (Cronbach’s alpha) for the IR subscale, indicating that these three items measure a single underlying construct effectively.

While the ORA and NORA dimensions are measured by single items, limiting standard internal consistency checks, their test-retest reliability over short periods is generally high, confirming their stability as measures of religious behavior. The overall stability and consistency across diverse samples confirm the DUREL’s reliability as a brief measure of religious commitment.

Factor Analysis

Factor analysis consistently supports the three-dimensional structure of the DUREL. Exploratory and confirmatory factor analyses performed across various populations confirm that the five items load onto three conceptually distinct factors: Organizational Religious Activity (Item 1), Non-organizational Religious Activity (Item 2), and Intrinsic Religiosity (Items 3, 4, and 5).

This clear factorial structure reinforces the scale’s utility, allowing researchers to analyze the unique contributions of behavioral (ORA, NORA) and cognitive/experiential (IR) aspects of faith separately when investigating their correlation with health variables. The stability of this three-factor model is a key strength cited in the literature, including the validation studies of the Persian version.

Instrument

Test Type: Self-report questionnaire / Brief epidemiological screening tool.

Format: Five items utilizing Likert-type response scales (6-point scale for activity items; 5-point scale for belief items).

Language Available: English, Farsi/Persian, and numerous other translations exist due to its widespread use in international health research.

Population Group: General population; utilized extensively in clinical and patient populations.

Age Group: Adults (typically 18+).

Population Details: Originally developed based on data from Duke University health studies; validated across various religious backgrounds (Christian, Muslim, etc.).

Test Methodology: Paper-and-pencil or electronic administration; rapid assessment (takes less than two minutes to complete).

Keywords

Duke University Religion Index, DUREL, Health research, ORA, NORA, IR, Spiritual assessment, Epidemiology, Psychological testing.

Authors

Author ORCID Identifier: Not provided in source content.

Affiliation Email addresses: [email protected] (Harold G. Koenig).

Correspondence Address: Center for Spirituality, Theology and Health, Duke University Medical Center, Durham, NC, USA.

Permissions & Fee and Test Year

The DUREL is generally considered a publicly available instrument for non-commercial research purposes, but researchers are strongly encouraged to contact Dr. Harold G. Koenig for formal permission and guidelines on usage, particularly for commercial applications or adaptations. The initial conceptual work leading to the DUREL was noted in Hill & Hood (1999), and the formalized five-item measure structure was detailed by Koenig and Büssing in 2010.

The definitive article detailing the instrument is available online. The instrument can be found on page 79 of “The Duke University Religion Index (DUREL): A Five-Item Measure for Use in Epidemiological Studies.” Available online at: http://www.mdpi.com/2077-1444/1/1/78.

Reference’s

• Hill‚ P. C.‚ & Hood‚ R. W.‚ Jr. (Eds.). (1999). Measures of religiosity. Birmingham‚ AL: Religious Education Press.
• Koenig‚ H.G‚ Büssing. A‚. (2010). The Duke University Religion Index (DUREL): A Five-Item Measure for Use in Epidemiological Studies. Religions‚ 1(1)‚ 78-85.
• Hafizi‚ S.‚ Memari‚ A. H.‚ Pakrah‚ M.‚ Mohebi‚ F.‚ Saghazadeh‚ A.‚ & Koenig‚ H. G. (2013). The Duke University Religion Index (DUREL): Validation and reliability of the Farsi version [Abstract]. Psychological Reports‚ 112(1)‚ 151-159.
• Saffari. Mohsen‚ Mohammadi Zeidi. Isa‚ Pakpour. Amir H.‚ Koenig. Harold G‚. 2013. Psychometric Properties of the Persian Version of the Duke University Religion Index (DUREL): A Study on Muslims. Journal of Religion and Health. Volume 52‚ Issue 2‚ pp 631-641.

Items of the Duke University Religion Index (DUREL)

The DUREL consists of five items which map onto three dimensions: Organizational Religious Activity (ORA), Non-organizational Religious Activity (NORA), and Intrinsic Religiosity (IR).

1. How often do you attend church (mosque) or other religious meetings? (ORA)

   • 1 – Never; 2 – Once a year or less; 3 – A few times a year; 4 – A few times a month; 5 – Once a week; 6 – More than once/week

2. How often do you spend time in private religious activities‚ such as prayer‚ meditation or Bible (Koran) study? (NORA)

   • 1 – Rarely or never; 2 – A few times a month; 3 – Once a week; 4 – Two or more times/week; 5 – Daily; 6 – More than once a day

3. The following section contains 3 statements about religious belief or experience. Please mark the extent to which each statement is true or not true for you.

   In my life‚ I experience the presence of the Divine (i.e.‚ God) – (IR)

   • 1 – Definitely not true; 2 – Tends not to be true; 3 – Unsure; 4 – Tends to be true; 5 – Definitely true of me

4. My religious beliefs are what really lie behind my whole approach to life – (IR)

   • 1 – Definitely not true; 2 – Tends not to be true; 3 – Unsure; 4 – Tends to be true; 5 – Definitely true of me

5. I try hard to carry my religion over into all other dealings in life – (IR)

   • 1 – Definitely not true; 2 – Tends not to be true; 3 – Unsure; 4 – Tends to be true; 5 – Definitely true of me