Skip to main content

Advertisement

Table 3 Estimated Regression-adjusted Effect of CFS and ISF on Annual Healthcare Expenditures (in US Dollars, $)

From: The economic impact of chronic fatigue syndrome in Georgia: direct and indirect costs

All effects estimated relative to not-fatigued (NF) population, (Standard Errors in Parentheses)
  Linear Ordinary Least Squares (OLS) for Untransformed Cost (y)
  Total Expenditures ($2005) Inpatient Hospital Expenditures ($2005) Ambulatory Provider Visits ($2005) Rx Medications ($2005) OTC Medications ($2005) Other Health Costs ($2005)
Incremental Expenditures attributed to CFS 3084.95*** (799.09) 476.11 (437.06) 1590.70*** (598.98) 919.18*** (293.37) 111.99*** (36.98) -13.03 (12.43)
Incremental Expenditures Attributed to ISF 1119.75** (476.46) 262.89 (254.04) 364.41 (272.99) 448.54*** (142.68) 31.81 (26.80) 12.09 (11.35)
AIC 8303.74 7815.93 7654.30 6969.76 5196.03 6361.90
BIC 8306.15 7818.34 7656.70 6972.17 5198.44 6364.30
  Generalized Linear Model for Untransformed Cost ((y+1)) a
Incremental Expenditures attributed to CFS 3285.54*** (1026.50) 519.95 (582.17) 1343.25** (587.55) 1241.13* (694.19) 204.01* (111.16) -1.83 (1.28)
Incremental Expenditures Attributed to ISF 1058.27*** (352.68) 71.61 (122.50) 384.73 (250.49) 317.41** (131.90) 46.83 (30.66) 0.82 (1.37)
AIC 17.33 11.12 16.62 12.54 10.37 2.68
BIC -2045.41 1178.77 -1739.82 -205.99 -925.17 -2767.13
  Two-Part Model (TPM) for Untransformed Cost (y)b
Incremental Expenditures Attributed to CFS 3618.21*** (1285.90) 602.70 (907.17) 1622.69*** (553.52) 1192.25*** (391.32) 189.13*** (54.14) -16.30 (21.12)
Incremental Expenditures Attributed to ISF 1151.63 (751.45) 128.18 (577.98) 416.12 (322.03) 473.56*** (180.19) 63.30** (25.14) 30.11 (37.49)
AIC 292.26 150.16 463.65 548.09 564.80 86.65
BIC -2113.67 1359.96 -1250.64 371.70 -328.59 -1313.92
  1. * p < 0.1, ** p < 0.05, ***p < 0.01.
  2. # Full GLM results in Additional file 2, Table S2.
  3. AIC: Akaike's information criterion; BIC: Schwarz's information criterion.
  4. a Generalized Linear Model with Gamma distribution and the log link function for all the categories of healthcare expenditures except for "Other Health Costs" with inverse Gaussian distribution.
  5. b Two-part model: the first part using a logistic regression for binary indicator (healthcare users vs. no-users) and the second part using GLM for positive healthcare costs.