title: Evaluation of techniques for handling missing cost-to-charge ratios in the USA Nationwide Inpatient Sample: a simulation study.
abstract: OBJECTIVE
  Evaluate performance of techniques used to handle missing cost-to-charge ratio (CCR) data in the USA Healthcare Cost and Utilization Project's Nationwide Inpatient Sample.
  
  
  METHODS
  Four techniques to replace missing CCR data were evaluated: deleting discharges with missing CCRs (complete case analysis), reweighting as recommended by Healthcare Cost and Utilization Project, reweighting by adjustment cells and hot deck imputation by adjustment cells. Bias and root mean squared error of these techniques on hospital cost were evaluated in five disease cohorts.
  
  
  CONCLUSIONS
  Similar mean cost estimates would be obtained with any of the four techniques when the percentage of missing data is low (<10%). When total cost is the outcome of interest, a reweighting technique to avoid underestimation from dropping observations with missing data should be adopted.
authors.affiliation: Outcomes Research Methods & Analytics, US Health Economics & Outcomes Research, Novartis Pharmaceuticals Corporation, One Health Plaza, East Hanover, NJ 07936, USA.
authors.forename: Tzy-Chyi
authors.initials: TC
authors.lastname: Yu
authors.affiliation: KMK Consulting, Inc., 7, North Tower, 23 Headquarters Plaza, Morristown, NJ 07960, USA.
authors.forename: Huanxue
authors.initials: H
authors.lastname: Zhou
mesh_terms: D057186:Comparative Effectiveness Research / Q000379:methods*; D003627:Data Interpretation, Statistical; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data*; D012107:Research Design; D014481:United States
keywords: Nationwide Inpatient Sample; cost-to-charge ratio; hospitalization costs; missing data; reweighting