Background: For humanitarian organisations to respond effectively to complex crises, they require access to up-todate evidence-based guidance. The COVID-19 crisis has highlighted the importance of updating global guidance to context-specific and evolving needs in humanitarian settings. Our study aimed to understand the use of evidence-based guidance in humanitarian responses during COVID-19. Primary data collected during the rapidly evolving pandemic sheds new light on evidence-use processes in humanitarian response.

Methods: We collected and analysed COVID-19 guidance documents, and conducted semi-structured interviews remotely with a variety of humanitarian organisations responding and adapting to the COVID-19 pandemic. We used the COVID-19 Humanitarian platform, a website established by three universities in March 2020, to solicit, collate and document these experiences and knowledge.

Results: We analysed 131 guidance documents and conducted 80 interviews with humanitarian organisations, generating 61 published field experiences. Although COVID-19 guidance was quickly developed and disseminated in the initial phases of the crisis (from January to May 2020), updates or ongoing revision of the guidance has been limited. Interviews conducted between April and September 2020 showed that humanitarian organisations have responded to COVID-19 in innovative and context-specific ways, but have often had to adapt existing guidance to inform their operations in complex humanitarian settings.

Conclusions: Experiences from the field indicate that humanitarian organisations consulted guidance to respond and adapt to COVID-19, but whether referring to available guidance indicates evidence use depends on its accessibility, coherence, contextual relevance and trustworthiness. Feedback loops through online platforms like the COVID-19 Humanitarian platform that relay details of these evidence-use processes to global guidance setters could improve future humanitarian response.

Keywords: COVID-19, Humanitarian, Evidence, Guidance, Online platform