Description

A dataset containing the SOFA scores (Vincent et al, 1996). for 520 patients, hospitalized in the intensive care unit (ICU) with Acute Lung Injury. Daily measurements are available for as long as each one remains in the ICU. This is an example of variable-domain functional data, as described by Gellar et al. (2014).

Usage

Format

A data frame with 520 rows (subjects) and 7 variables:

death

binary indicator that the subject died in the ICU

SOFA

520 x 173 matrix in variable-domain format (a ragged array). Each column represents an ICU day. Each row contains the SOFA scores for a subject, one per day, for as long as the subject remained in the ICU. The remaining cells of each row are padded with NAs. SOFA scores range from 0 to 24, increasing with severity of organ failure. Missing values during one's ICU stay have been imputed using LOCF.

SOFA_raw

Identical to the SOFA element, except that it contains some missing values during one's hospitalization. These missing values arise when a subject leaves the ICU temporarily, only to be re-admitted. SOFA scores are not monitored outside the ICU.

los

ICU length of stay, i.e., the number of days the patient remained in the ICU prior to death or final discharge.

age

Patient age

male

Binary indicator for male gender

Charlson

Charlson co-morbidity index, a measure of baseline health status (before hospitalization and ALI).

Details

The data was collected as part of the Improving Care of ALI Patients (ICAP) study (Needham et al., 2006). If you use this dataset as an example in written work, please cite the study protocol.

References

Vincent, JL, Moreno, R, Takala, J, Willatts, S, De Mendonca, A, Bruining, H, Reinhart, CK, Suter, PM, Thijs, LG (1996). The SOFA ( Sepsis related Organ Failure Assessment) score to describe organ dysfunction/failure. Intensive Care Medicine, 22(7): 707-710.

Needham, D. M., Dennison, C. R., Dowdy, D. W., Mendez-Tellez, P. A., Ciesla, N., Desai, S. V., Sevransky, J., Shanholtz, C., Scharfstein, D., Herridge, M. S., and Pronovost, P. J. (2006). Study protocol: The Improving Care of Acute Lung Injury Patients (ICAP) study. Critical Care (London, England), 10(1), R9.

Gellar, Jonathan E., Elizabeth Colantuoni, Dale M. Needham, and Ciprian M. Crainiceanu. Variable-Domain Functional Regression for Modeling ICU Data. Journal of the American Statistical Association, 109(508):1425-1439, 2014.