The Effects of Spanish-Language Materials in a Local Area ABS Mixed-Mode Survey on Response Rates and Sample Composition: An Experiment

Including respondents who speak languages other than English is crucial for accurately representing the population. Past experiments in the United States have often focused on geographic areas with high concentrations of Spanish-language speakers. The effects of including Spanish-language materials in push-to-web surveys for geographic areas with fewer Spanish-language speakers are underexplored. We conducted an experiment in the 2023 Central Nebraska Labor Availability Survey (American Association for Public Opinion Research [AAPOR] Response Rate 2 [RR2]=15.5%, n=1,422), a concurrent mixed-mode web-and-mail survey of adults living in the central part of Nebraska. About 7% of all adults in Nebraska and almost 12% of adults in this area speak Spanish at home. All survey materials were translated from English to Spanish using a committee approach. Addresses (n=9,500) were randomly assigned to receive either English-only materials or the materials in both English and Spanish; all households could access a Spanish-language web questionnaire. Adding Spanish-language materials significantly decreased the response rate, yielded few Spanish-language responses, but brought in younger adults, yielding a more representative sample based on age. Mode selection varied across language use; 66.7% of respondents overall answered by mail, but mail was used by 85.7% of Spanish-language respondents.