Assessing the Use of a Pre-Field Screening Service to Identify Nonworking Cellphone Numbers in Ohio
Marcus E. Berzofsky
RTI International
Kimberly C. Peterson
RTI International
Bo Lu
Division of Biostatistics, Ohio State University
Howard Speizer
RTI International
Timothy Sahr
Ohio Colleges of Medicine Government Resource Center
Most RDD telephone surveys have introduced a cellphone frame to augment the landline sample to improve coverage and reduce variance. However, due to a number of challenges including the restrictions in how cellphone numbers can be dialed, it can be more expensive to complete cellphone interviews and often for this reason the proportion of the total sample allocated to the cell phone frame has been kept artificially small to reduce data collection costs. As more people shift away from using land lines it becomes increasingly important to increase the allocation of RDD sample to the cellphone frame. These persons tend to be younger, more likely to have children, and minority. Sample vendors are increasing the information attached to cellphone numbers to help improve performance and in this paper we investigate the effectiveness of the Cell-Wins service provided by MSG which flags cellphone numbers that are actively being used. If accurate, this flag could reduce data collection costs by identifying nonworking numbers prior to data collection. We present an assessment of this flag in Ohio which includes an evaluation of the resulting undercoverage and cost efficiencies gained.