Measuring stroke outcomes for 74 501 patients using linked administrative data: System-wide estimates and validation of 'home-time' as a surrogate measure of functional status

Aims Administrative data offer cost-effective, whole-of-population stroke surveillance yet the lack of validated measures of functional status is a shortcoming. The number of days spent living at home after stroke ('home-time') is a patient-centred outcome that can be objectively ascertained from administrative data. Population-based validation against both severity and outcome measures and for all subtypes is lacking. We aimed to report representative 'home-time' estimates and validate 'home-time' as a surrogate measure of functional status after stroke. Methods Stroke hospitalisations from a state-wide census in New South Wales, Australia, from January 1, 2005 to March 31, 2014 were linked to prehospital data, poststroke admissions and deaths. We correlated 90-day 'home-time' with Glasgow Coma Scale (GCS) scores, measured upon a patient's initial contact with paramedics and Functional Independence Measure (FIM) scores, measured upon entry to rehabilitation after the acute hospital stroke admission. Negative binomial regressions identified predictors of 'home-time'. Results Patients with stroke (N = 74 501) spent a median of 53 days living at home 90 days after the event. Median 'home-time' was 60 days after ischaemic stroke, 49 days after subarachnoid haemorrhage and 0 days after intracerebral haemorrhage. GCS and FIM scores significantly correlated with 'home-time' (P < .001). Women spent significantly less time at home compared with men after stroke, although being married increased 'home-time' after ischaemic stroke and subarachnoid haemorrhage. Conclusions These findings underscore the immediate and adverse impact of stroke. 'Home-time' measured using administrative data is a robust, replicable and valid patient-centred outcome enabling inexpensive population-based surveillance and system-wide quality assessment.