PREDICTIVE-VALIDITY OF THE NURSING SEVERITY INDEX IN PATIENTS WITH MUSCULOSKELETAL DISEASE

Prior studies have not examined the validity of severity of illness in struments in patients at low risk for mortality. We, therefore, examin ed the predictive validity of a newly developed instrument, the Nursin g Severity Index in 5347 adult medical and surgical patients with musc uloskeletal diagnoses admitted to an academic medical center in 1985-8 8. The Index is based on aggregating 34 clinical observations which we re recorded by primary nurses during patient care; observations reflec t biologic, functional, cognitive and psychosocial abnormalities. Othe r data, including patient demographic data and outcomes were obtained from hospital data bases. We found that, among all study patients, adm ission Nursing Severity Index scores were highly related (p < 0.001) t o in-hospital death rates-which were 0, 0.4, 0.8, 2.6, 6.7 and 23.5% i n six hierarchical strata defined by the Index-and to nursing home dis charge rates. In multivariate analyses, adjusting for diagnosis and ot her important covariates, each strata was associated with a 2.5-fold i ncreased risk of mortality and a 1.6-fold increased risk of nursing ho me discharge, In addition, the Nursing Severity Index was an independe nt predictor (p < 0.001) of hospital charges and length of stay. We co nclude that the Nursing Severity Index assesses multiple dimensions of illness, can be easily recorded during routine patient care: and accu rately predicts hospital outcomes in an important 'low risk' group of patients. The validity of the Nursing Severity Index in other clinical subgroups should be further studied.