Table 4.

Linear regression models for treatment type as a predictor of log_e-transformed total hospitalization charges – 2002-2014 Nationwide Inpatient Sample ^*

TPE vs. IVIG: †	β	95% CI
OVERALL:
Model 1 – Unadjusted	0.20	0.16, 0.25
Model 2 – Risk-Adjusted	0.21	0.16, 0.26
Model 3 – Propensity-score adjusted	0.19	0.14, 0.24
Model 4 – Propensity-score matched	0.21	0.14, 0.29
MALE:
Model 1 – Unadjusted	0.21	0.14, 0.27
Model 2 – Risk-Adjusted	0.19	0.13, 0.25
Model 3 – Propensity-score adjusted	0.19	0.12, 0.25
Model 4 – Propensity-score matched	0.22	0.13, 0.31
FEMALE:
Model 1 – Unadjusted	0.20	0.13, 0.27
Model 2 – Risk-Adjusted	0.24	0.17, 0.30
Model 3 – Propensity-score adjusted	0.19	0.11, 0.26
Model 4 – Propensity-score matched	0.19	0.09, 0.29
Period 1 (2002-2007):
Model 1 – Unadjusted	0.39	0.32, 0.47
Model 2 – Risk-Adjusted	0.31	0.23, 0.38
Model 3 – Propensity-score adjusted	0.38	0.31, .46
Model 4 – Propensity-score matched	0.39	0.31, 0.49
Period 2 (2008-2014):
Model 1 – Unadjusted	0.32	0.26, 0.37
Model 2 – Risk-Adjusted	0.31	0.25, .36
Model 3 – Propensity-score adjusted	0.30	0.24, .36
Model 4 – Propensity-score matched	0.33	0.25, 0.40

^*Note 1: No significant interaction by sex or time period in unadjusted, risk-adjusted or propensity-score adjusted models.

^†Note 2: Risk-adjusted models include age group, Charlson comorbidity index and admission status as covariates. Propensity score adjustment or matching was based on a logistic regression model that includes age group, Charlson comorbidity index and admission status as covariates.

Abbreviations: CI=Confidence Interval, IVIG=Intravenous Immunoglobulin, TPE = Therapeutic plasma exchange.