Table 3.

Comparison of SD of predicted and unpredicted variation using 6-month pooled data (July to December 2003)

ModelCase-Mix AdjustorsR2 (%)SD of Predicted MAC/SessionSD of PredictionError
1Demographics (age, race, sex)2.8110.2760.38
2Add time since start of renal replacement therapy4.6813.2559.80
3Add body size5.5214.3959.54
4Add baseline hematocrit6.5015.6259.23
5Add functional status and comorbidities (with 3 age–comorbid interaction terms)11.7521.0057.54
5aAdd functional status and comorbidities and use more recent Hct measure (with 3 age–comorbid interaction terms)16.0624.5556.12
6Add previous hospitalization (with 3age–comorbid interaction terms)15.2323.9056.39
  • The standard deviation of MAC/session is $61.25.