1. Do cell phone users differ by frame and should we care? Presenter Michel Boudreaux AAPOR, Phoenix, Arizona May 13, 2011 Funded by a grant from the Robert Wood Johnson Foundation

2. Acknowledgments Funding support: MN Department of Human Services MN Department of Health Coauthors: Kathleen Thiede Call Donna McAlpine Tim Beebe Brett Fried David Dutwin 2

3. 3 National/Midwest Cell Phone Use

4. To screen or not to screen Lack of consensus in field on whether to: Screen for cell phone only (CO) households Include all but landline mostly Interview the entire cell phone frame Excluding some cell users could introduce error Including all users complicates weighting due to overlapping probabilities of selection 4

5. Research questions Are cases omitted when screening for CO households different depending on which frame they are captured in (LL vs. Cell)? Do these differences disappear when controlling for post-stratification variables? 5

6. Data Sources 2009 MN Health Access Survey (MNHA) Ongoing survey of health insurance/access Accepted all cell phone completes 2010 MN Survey on Adult Substance Use Focus on prevalence of drug/alcohol use and treatment patterns Accepted only CO and CM cases 6

7. Analysis T-test/pairwise comparisons of: Cell mostly sampled in LL versus Cell frame Regression models with telephone usage as predictor, controlling for weighting variables Full sample weights applied 7

8. Unadjusted Demographics, MNHA 8 * *

9. Unadjusted Health Insurance, MNHA 9 * *

10. Adjusted Health Insurance, MNHA 10

11. Unadjusted Demographics, MNSASU 11 *

12. Unadjusted Health-Related Outcomes, MNSASU 12 *

13. Adjusted Health-Related Outcomes, MNSASU 13

14. Discussion CM users from landline vs. cell frames do differ on health outcomes However, post-stratification weighting appears to correct for these differences This suggests that we can safely screen for CO However, cost and variance remains an issue 14

15. 15 Contact information Michel Boudreaux State Health Access Data Assistance Center (SHADAC) boudr019@umn.edu ©2002-2009 Regents of the University of Minnesota. All rights reserved.The University of Minnesota is an Equal Opportunity Employer