Validity and reliability of Resource Utilization Groups (RUG-III) in Finnish long-term care facilities.

Resource Utilization Groups, Version III (RUG-III) is a case-mix system developed in the USA for classification of long-term care residents. This paper examines the validity and reliability of an adapted 22-group version of RUG-III (RUG-III/22) for use in long-term care facilities in Finland. Finnish cost weights for RUG-III/22 groups are calculated and different methods for their computation are evaluated. The study sample (1,964 residents) was collected in 1995-96 from ten long-term care facilities in Finland. RUG-III/22 alone explained 38.2% of the variance of total patient-specific (nursing + auxiliary staff) per diem cost. Resource use within RUG groups was relatively homogeneous. Other predictors of resource use included age, gender and length of stay. RUG-III/22 also met the standard for good reliability (i.e. a kappa value of 0.6 or higher) for crucial classification items, such as activities of daily living and high correlation between assessments based on relative cost.