Talk or text? : evaluating response rates by remote survey method during Covid-19

Researchers and policy makers face significant challenges in selecting a method to conduct remote surveys, especially when collecting sensitive information or during turbulent life stages of hard-to-reach groups. In the context of the COVID-19 lockdown, we randomly selected about 600 adults in El Salvador to survey using two different tools: telephone interviews or a self-completion survey via WhatsApp. We find that phone-based surveys increase the rate of survey completion by 42 percentage points. We document even larger effects for women and older adults. Although direct costs of phone-based surveys are substantially larger - doubling implementation cost - our estimates imply that when adjusted for the probability of completion, the costs of conducting phone-based surveys can be 25 percent lower.