# Measuring religiosity: comparison of single-item measures with validated scales in a UK cohort study (ALSPAC)

## TL;DR

This study compares single-item and validated measures of religiosity in the ALSPAC cohort to understand how well they capture different aspects of religiosity.

## Contribution

The paper evaluates the validity of single-item religiosity measures in ALSPAC and their alignment with theorised dimensions of religiosity.

## Key findings

- Pre-validated religiosity measures did not always function as intended in ALSPAC.
- Single-item measures grouped into belief-based and behaviour-based factors but did not align well with hypothesised dimensions.
- Results were consistent across both parent and offspring generations in ALSPAC.

## Abstract

Many studies use single-item variables to measure religiosity, such as religious belief, identity or service attendance. However, there are many different hypothesised dimensions of religiosity and it is often unclear how these single-item measures may map onto these theorised constructs. ALSPAC (Avon Longitudinal Study of Parents and Children) primarily relied on single-items to measure religiosity, but more recently has included validated questionnaires (DUREL [Duke University Religion Index] and I/EMSS [Intrinsic/Extrinsic Measurement: I/E-Revised and Single-Item Scales]). This paper aims to: i) confirm whether the validated measures work as intended in ALSPAC; and ii) understand which religiosity dimensions the single-item measures relate to.

Twenty religiosity questions were asked to ALSPAC offspring and parents approximately 28 years after the offspring’s birth. We used three exploratory factor analyses to assess how the different items related to one another on: i) the pre-validated DUREL and I/EMSS measures to ensure they function as intended; ii) all 20 religiosity measures; and iii) the pre-validated measures and the single-item measures also used at previous ALSPAC timepoints (13 measures).

The first factor analysis showed that, beyond a single religiosity factor, these pre-validated items did not always work as intended. For instance, intrinsic religiosity items loaded together, but extrinsic religiosity items were often separated. The second and third analyses showed that single-item measures did not relate well to hypothesised dimensions of religion but did form two broad factors of belief-based and behaviour-based items. Results were broadly comparable across both ALSPAC generations.

These results show that pre-validated measures of religiosity do not always behave as expected in ALSPAC, while the single-item measures do not easily map onto specific dimensions of religiosity. These results will help researchers better understand the ALSPAC religiosity data and contribute to the debate on the factor structure of religion more broadly.

A person’s religiosity encompasses a huge range of factors and considerations, this makes measuring religiosity very difficult. To avoid over-burdening participants of questionnaires, difficult choices have to be made on which questions are most important to include. In general, researchers try to include as many aspects of religion as possible. Some of the main categories of religious measures include whether they are done on your own or in public and these are further categorised into whether they are internal beliefs or whether they include a behaviour.

We aimed to find how our measures of religiosity at ALSPAC fit with existing ideas on how to categorise religiosity. We did this by using ‘factor analysis’, this is a technique that helps identify the underlying patterns between measures to help group them together into ‘factors’. The hope was that these factors would align with existing ideas of how religious measures should be categorised.

However, despite using some pre-validated measures to help calibrate the analysis the measures did not align as well as hoped with existing literature. Measures relating to more belief based characteristics separated from behaviour based measures but most other results do not lend themselves to easy interpretation.