Landline and Cell Phone Response Measures in Behavioral Risk Factor Surveillance System

Abstract

Landline RDD surveys are facing a coverage problem due to increasing cell phone only households in the US. To address this issue, the Behavioral Risk Factor Surveillance System (BRFSS) included cell phone samples in 2009. BRFSS landline and cell phone data for 2009 were used to examine the differences between landline and cell phone data in several response measures, which included: response and cooperation rates, percent completed screening question, percent completed interview and percent refusal/break-off the interview. The completion rates and refusal/break-off rates are estimated overall and among those completed screening questions, for the total sample and by state. Cell phone samples were less likely to be answered than landline samples. The dispositions of cell phone calls were more likely to be noted as answering devices/voicemail, no response or refusal/break-offs. Cell phone respondents were also less likely to complete screening questions. However, among respondents who completed screening questions, cell phone respondents were more likely to complete the survey and less likely to refuse or break-off, a pattern which was noted in the majority of states. Also, response and cooperation rates show different pictures in the landline and cell phone samples, where landlines had higher response rate than cell phones, and cell phones had higher cooperation rates than landlines. The results provide valuable information on the importance of pursuing better strategies to overcome barriers to higher completion of screening questions and success at the initial stage of the interview. Such effects could improve the overall response rate and under coverage bias in the landline.