Methodology of Natsal-COVID Wave 2: A large, quasi-representative, longitudinal survey measuring the impact of COVID-19 on sexual and reproductive health in Britain

Emily Dema; Anne Conolly; Malachi Willis; Andrew J Copas; Soazig Clifton; Margaret Blake; Julie Riddell; Raquel Bosó Pérez; Clare Tanton; Chris Bonell; Pam Sonnenberg; Catherine H Mercer; Kirstin R Mitchell; Nigel Field

doi:10.12688/wellcomeopenres.17850.1

Methodology of Natsal-COVID Wave 2: A large, quasi-representative, longitudinal survey measuring the impact of COVID-19 on sexual and reproductive health in Britain

Wellcome Open Res. 2024 Jan 8:7:166. doi: 10.12688/wellcomeopenres.17850.1. eCollection 2022.

Authors

Emily Dema^#¹, Anne Conolly^#^{1

2}, Malachi Willis³, Andrew J Copas¹, Soazig Clifton^{1

2}, Margaret Blake⁴, Julie Riddell³, Raquel Bosó Pérez³, Clare Tanton⁵, Chris Bonell⁵, Pam Sonnenberg¹, Catherine H Mercer¹, Kirstin R Mitchell^#³, Nigel Field^#¹

Affiliations

¹ Institute for Global Health, University College London, Mortimer Market Centre, London, WC1E 6JB, UK.
² NatCen Social Research, 35 Northampton Square, London, EC1V 0AX, UK.
³ MRC/CSO Social and Public Health Sciences Unit, University of Glasgow, 99 Berkeley Street, Glasgow, G3 7HR, UK.
⁴ Ipsos, 3 Thomas More Square, London, E1W 1YW, UK.
⁵ Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.

^# Contributed equally.

Abstract

Background: The National Surveys of Sexual Attitudes and Lifestyles COVID study (Natsal-COVID) was designed to understand the impact of COVID-19 on Britain's sexual and reproductive health (SRH). 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. We describe the Wave 2 survey methodology and assess the sample representativeness.

Methods: Natsal-COVID Wave 2 was conducted March-April 2021; approximately one year after the start of Britain's first national lockdown. Data were collected using an online web-panel survey administered by Ipsos. The sample comprised a longitudinal sample of Wave 1 participants who had agreed to re-contact plus a sample of participants residing in Britain, aged 18-59, including a boost sample comprising people aged 18-29. Questions covered reproductive health, relationships, sexual behaviour and SRH service use. Quotas and weighting were used to achieve a quasi-representative sample of the British population. Comparisons were made with recent national probability surveys, Natsal-3 (2010-12) and Natsal-COVID Wave 1 to understand bias.

Results: A total of 6,658 individuals completed the survey. In terms of gender, age, ethnicity, and rurality, the weighted Natsal-COVID Wave 2 sample was like the general population. Participants were less likely to be married or to report being in good health than the general population. The longitudinal sample (n=2,098) were broadly like participants who only took part in Wave 1 but were older. Among the sexually active, longitudinal participants were less likely to report multiple sexual partners or a new sexual partner in the past year compared to those who only took part in Wave 1.

Conclusions: Natsal-COVID collected longitudinal, quasi-representative population data to enable evaluation of the population-level impact of COVID-19 on SRH and to inform policy.

Keywords: COVID-19; cross-sectional and longitudinal data; online survey; population estimates; relationships; sexual behaviour; sexual health.

Abstract

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