Study title

Abstract copyright UK Data Service and data collection copyright owner.The British National Surveys of Sexual Attitudes and Lifestyles (Natsal) have been undertaken decennially since 1990 and provide a key data source underpinning sexual and reproductive health (SRH) policy. Further information is available from the Natsal website. Natsal-COVID:The COVID-19 pandemic disrupted many aspects of sexual lifestyles, triggering an urgent need for population-level data on sexual behaviour, relationships, and service use at a time when gold-standard in-person, household-based surveys with probability sampling were not feasible. The Natsal-COVID study was designed to understand the impact of COVID-19 on the nation's sexual and reproductive health (SRH) and assessed the sample representativeness. The study was funded by the Chief Scientist Office, the Wellcome Trust (with contributions from ESRC and NIHR), the UCL Covid-19 Rapid Response Fund and the Medical Research Council. The Natsal-COVID Wave 1 survey and qualitative follow-up interviews were conducted in 2020. The Wave 2 survey was designed to capture one-year prevalence estimates for key SRH outcomes and measure changes over the first year of the pandemic.Methods: The Natsal-COVID Wave 1 survey was conducted four months after the announcement of Britain's first national lockdown (23 March 2020), between 29 July and 10 August 2020. Wave 1 was an online web-panel survey administered by survey research company, Ipsos MORI. Eligible participants were resident in Britain, aged 18-59 years, and the sample included a boost of those aged 18-29. Questions covered participants' sexual behaviour, relationships, and SRH service use. Quotas and weighting were used to achieve a quasi-representative sample of the British general population. Participants meeting the criteria of interest and agreeing to recontact were selected for qualitative follow-up interviews. Comparisons were made with contemporaneous national probability...