Abstract
Mainstream religious beliefs and behaviours have been shown to have positive effects on health and well-being, but there has been increasing secularisation in the West over time. With concurrent increases in those stating they have no religion (the 'nones') there are increasing numbers now describing themselves as humanist, 'spiritual but not religious' or who have sought alternative forms of belief. Others have formed their own beliefs using elements of different belief systems. This trend is reflected in ALSPAC data with larger proportions considering themselves as 'nones', agnostic or atheist, and about 3% of parent participants consistently stating they had 'other' beliefs. The main aim of this paper is to describe the coding of the Christian denominations, world religions, non-mainstream beliefs (NMB) and non-religious groups derived from the text-based data collected from the original mother and partner cohorts (G0). This spans a period of ~28 years from pregnancy onwards. We also describe the coding of text-based responses from their offspring (G1) collected at ages 27+ and 29+. The creation of this coded data will enable researchers to compare between the Christian denominations and/or other belief groups taken from two generations alongside the rich resource of physical and mental health, behavioural and social data that exists within ALSPAC.