Table 2

Patient variables—collected at enrolment

Patient variables—collected at enrolmentCollection method
Age/sex/ethnicity/race demographic dataChart review
Body mass indexChart review
Comorbidities: Charlson* and functional indices**Chart review
Baseline function: Functional Status Score for ICU77 Proxy interview (see Outcomes below)
Baseline function: Katz Activities of Daily Living Scale154 and Lawton IADLProxy interview (see Outcomes below)
Baseline function: SF-36 Physical Function domain and walk impairment questionProxy interview
Clinical Frailty ScaleProxy interview
ICU admission diagnosis (eg, sepsis, renal failure)Chart review
Severity of illness: APACHE II†Chart review
Patient location immediately prior to ICU and to hospital admissionChart review
  • *Charlson Index: a score for  in- patients derived from 19 comorbidities; an increased score reflecting increased  1 -year   mortality. 155

  • **Functional Index: an 18-diagnosis scale for ICU  patients   predicting  1 - year   SF-36 Physical Function score; increased score reflecting worse function. 156–158  

  • †APACHE II:  a   severity of illness index using age, medical conditions   and acute physiology, with higher scores reflecting  increased  short-term mortality. 159

  • IADL, instrumental activities of daily living; ICU, intensive care unit.