Predictors of mortality in elderly subjects with obstructive airway disease: the PILE score.
Mehrotra N, Freire AX, Bauer DC, Harris TB, Newman AB, Kritchevsky SB, Meibohm B. Predictors of mortality in elderly subjects with obstructive airway disease: the PILE score. Ann Epidemiol. 2010 Mar; 20(3):223-32.