TABLE 1.

Eligibility criteria for selecting studies. Wales, United Kingdom, 2023.

	Inclusion criteria	Exclusion criteria
Population	People aged 16 and over experiencing homelessness during COVID-19 pandemic	No research on homeless population
	Using the ETHOS definition of homelessness, see Supplementary Table S1 [20]	People under the age of 16
Exposure	COVID-19 outbreak	Other previous pandemics/diseases
Comparisons	i. Describing the outcomes of COVID-19 in the homeless population and comparing them to the general population, to other marginalised populations, between subtypes of homelessness, or over time	No comparison
	ii. Describing the inequalities experienced by the homeless population and comparing them with before the COVID-19 pandemic
Outcome measures	Studies on clinical outcomes related to COVID-19: rates of COVID-19 infection, hospitalisation rates, mortality rates, mental health impact, and long COVID rates	Clinical outcomes of COVID-19 not measured
	Studies looking at mediators which affect COVID-19 outcomes, including but not limited to attitudes to COVID-19, testing rates, vaccination uptake, adoption of personal protective behaviours, and accessibility to healthcare/other services
	Studies reporting on the impact of the COVID-19 pandemic on wider health and socioeconomic inequalities
Study design	Hierarchy of evidence, prioritising primary research studies with a comparison. Both quantitative and qualitative studies were reviewed. Grey literature considered if providing empirical data	Opinion pieces without empirical data
		Systematic reviews (References lists checked)
Language	English	Not published in English
Publication date, type	During/Since start of pandemic, published and preprint	Prior to 2020