211103 Weighting Cell Phone Surveys

Tuesday, November 10, 2009: 3:00 PM

Randal S. ZuWallack, MS , ICF Macro, Burlington, VT
Frederica R. Conrey, PhD , ICF Macro, Burlington, VT
Objective: To develop and evaluate a strategy for weighting survey data collected via landline and cell phones.

Introduction: Combining survey data from cell phone and landline interviews is difficult because people who have both landline and cell phones have an increased probability of selection into the combined sample, and current, reliable estimates of wireless penetration and substitution in many populations are not available.

Method: We developed a method for weighting combined survey samples based on the assumption that people with certain characteristics have knowable propensities to appear in landline and cell phone samples. Based on data from a national cell phone survey and from the National Health Interview Survey, we developed a propensity weighting model for combining cell phone and landline data.

Results: Results from the application of the model to data from a national, a state-level, and a regional survey suggest that propensity weighting effectively combines landline and cell phone data, effectively reproducing independent estimates of wireless penetration and substitution.

Conclusions: Propensity weighting provides an easy, valid means of combining landline and cell phone survey data for which independent estimates of wireless penetration are not available.

Learning Objectives:
Discuss the challenges associated with weighting landline and cell phone survey data Describe an approach for weighting regional, state, and national-level data to accurately reflect the landline and cell phone populations Evaluate the success of the weighting strategy

Keywords: Data/Surveillance, Epidemiology

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: MS in Statistics. With coauthors, I conducted the statistical analysis described in the abstract.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.