Exploring the experiences of changes to support access to primary health care services and the impact on the quality and safety of care for homeless people during the COVID-19 pandemic: a study protocol for a qualitative mixed methods approach. - Howells, Kelly; Burrows, Martin; Amp, Mat; Brennan, Rachel; Yeung, Wan-Ley; Jackson, Shaun; Dickinson, Joanne; Draper, Julie; Campbell, Stephen; Ashcroft, Darren; Blakeman, Tom; Sanders, Caroline (International Journal for Equity in Health, 2021)