Validation of Resource Utilization Groups version III for Home Care (RUG-III/HC): evidence from a Canadian home care jurisdiction.
BACKGROUND
The case-mix system Resource Utilization Groups version III for Home Care (RUG-III/HC) was derived using a modest data sample from Michigan, but to date no comprehensive large scale validation has been done.


OBJECTIVE
This work examines the performance of the RUG-III/HC classification using a large sample from Ontario, Canada.


METHODS
Cost episodes over a 13-week period were aggregated from individual level client billing records and matched to assessment information collected using the Resident Assessment Instrument for Home Care, from which classification rules for RUG-III/HC are drawn. The dependent variable, service cost, was constructed using formal services plus informal care valued at approximately one-half that of a replacement worker.


RESULTS
An analytic dataset of 29,921 episodes showed a skewed distribution with over 56% of cases falling into the lowest hierarchical level, reduced physical functions. Case-mix index values for formal and informal cost showed very close similarities to those found in the Michigan derivation. Explained variance for a function of combined formal and informal cost was 37.3% (20.5% for formal cost alone), with personal support services as well as informal care showing the strongest fit to the RUG-III/HC classification.


CONCLUSIONS
RUG-III/HC validates well compared with the Michigan derivation work. Potential enhancements to the present classification should consider the large numbers of undifferentiated cases in the reduced physical function group, and the low explained variance for professional disciplines.
Poss
Jeffrey W
JW
Department of Health Studies and Gerontology, University of Waterloo, Waterloo, ON, Canada. jwposs@healthy.uwaterloo.ca
Hirdes
John P
JP
Fries
Brant E
BE
McKillop
Ian
I
Chase
Mary
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D002170:Canada; D003953:Diagnosis-Related Groups; D004180:Direct Service Costs; D005260:Female; D015577:Geriatric Assessment / Q000379:methods; D015276:Health Care Rationing / Q000191:economics / Q000458:organization & administration*; D006699:Home Care Services / Q000191:economics / Q000458:organization & administration*; D006801:Humans; D007345:Insurance Claim Review; D008297:Male; D008875:Middle Aged