MRC/CSO Social and Public Health Sciences Unit

The National Surveys of Sexual Attitudes and Lifestyles (Natsal) are large probability-sample bio-behavioural surveys, representative of the British population.  They are the largest surveys of sexual behavior in the world.

Three Natsal surveys have taken place at the turn of each decade since 1990, with a new wave of data collection (Natsal-4) due to begin in 2022. Natsal was initiated in response to the emerging HIV epidemic and has provided the evidence-base for development and monitoring of major sexual health interventions, including the National Chlamydia Screening Programme; enhanced HIV testing; HPV vaccination; and the Teenage Pregnancy Strategy.

In Natsal-4, interviewers will collect information from nearly 8,000 people aged 16-59 using computerised questionnaires to ensure privacy. Survey answers will be combined with information from biological samples (e.g. to test for sexually transmitted infections) and routinely-collected data (e.g. health records). Combining all four surveys will create a resource that provides a comprehensive picture of the sexual health of the nation and show how this has changed over time and across generations.

Natsal-4 is a collaboration between University College London (UCL), the London School of Hygiene & Tropical Medicine (LSHTM), the University of Glasgow and NatCen Social Research. It is funded by the Wellcome Trust, the National Institute for Health Research (NIHR) and the Economic and Social Research Council (ESRC).