Models for Predicting Survival in Inpatient Hospice Applicants

Parameters:

(1) gender

(2) pain

(3) no funds

(4) neoplasm

(5) Karnofsky score

(6) weakness

(7) congestive heart failure (CHF)

(8) hormonal therapy

(9) disoriented

The Karnofsky score can range from 0 to 100 (by 10's) but essentially should be in the range of 30 to 70. A patient with a higher Karnofsky score does not qualify for hospice care, while a person with a score less than 30 has a poor short term prognosis.

where:

• The wording for "no funds" is somewhat awkward.

X for death within 3 months =

= (-0.93 * (points for gender)) + (0.61 * (points for pain)) + (1.30 * (points for no funds)) + (1.66 * (points for neoplasm)) - (0.06 * (points for Karnofsky score)) + (1.57 * (points for weakness)) + (1.23 * (points for CHF)) + (0.48 * (points for hormones)) - (1.24 * (points for disoriented)) – 0.28

Y for death within 6 months =

= (-2.33 * (points for gender)) + (1.12 * (points for pain)) - (0.39 * (points for no funds)) + (1.92 * (points for neoplasm)) - (0.04 * (points for Karnofsky score)) + (1.12 * (points for weakness)) + (1.91 * (points for CHF)) + (2.02 * (points for hormones)) - (1.43 * (points for disoriented)) + 1.43

probability of death in time period =

= 1 / (1 + EXP((-1) * (variable)))

Performance:

• The model for death in 3 months classified 89% of patients correctly.

• The model for death in 6 months classified 94% of patients correctly.

• The false positive rate for the 3 month prediction was 10% and for the 6 month prediction was 5%.

• The false negative rate for the 3 month prediction was 25% and for the 6 month prediction was 17%.