title: Health Insurance Dynamics: Methodological Considerations and a Comparison of Estimates from Two Surveys.
abstract: OBJECTIVE
  To highlight key methodological issues in studying insurance dynamics and to compare estimates across two commonly used surveys.
  
  
  METHODS
  Nonelderly uninsured adults and children sampled between 2001 and 2011 in the Medical Expenditure Panel Survey and the Survey of Income and Program Participation.
  
  
  METHODS
  We utilized nonparametric Kaplan-Meier methods to estimate quantiles (25th, 50th, and 75th percentiles) in the distribution of uninsured spells. We compared estimates obtained across surveys and across different methodological approaches to address issues like attrition, seam bias, censoring and truncation, and survey weighting method.
  
  
  METHODS
  All data were drawn from publicly available household surveys.
  
  
  RESULTS
  Estimated uninsured spell durations in the MEPS were longer than those observed in the SIPP. There were few changes in spell durations between 2001 and 2011, with median durations of 14 months among adults and 5-7 months among children in the MEPS, and 8 months (adults) and 4 months (children) in the SIPP.
  
  
  CONCLUSIONS
  The use of panel survey data to study insurance dynamics presents a unique set of methodological challenges. Researchers should consider key analytic and survey design trade-offs when choosing which survey can best suit their research goals.
authors: Department of Health Policy, Vanderbilt University School of Medicine, Nashville, TN. john.graves@vanderbilt.edu.
authors: John A
authors: JA
authors: Graves
authors: Department of Health Policy, Vanderbilt University School of Medicine, Nashville, TN.
authors: Pranita
authors: P
authors: Mishra
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005102:Health Expenditures; D006801:Humans; D019458:Insurance Coverage / Q000706:statistics & numerical data*; D007348:Insurance, Health / Q000458:organization & administration* / Q000706:statistics & numerical data; D008137:Longitudinal Studies; D017057:Medically Uninsured / Q000706:statistics & numerical data*; D008875:Middle Aged; D011795:Surveys and Questionnaires; D014481:United States
keywords: Health insurance; duration models; survey methods; survival methods