Nurse Staffing and Health Outcomes of Psychiatric Inpatients: A Secondary Analysis of National Health Insurance Claims Data

ABSTRACT

Purpose@#The present study investigated the association between nurse staffing and health outcomes among psychiatric inpatients in Koreaby assessing National Health Insurance claims data. @*Methods@#The dataset included 70,136 patients aged 19 years who were inpatientsin psychiatric wards for at least two days in 2016 and treated for mental and behavioral disorders due to use of alcohol; schizophrenia,schizotypal and delusional disorders; and mood disorders across 453 hospitals. Nurse staffing levels were measured in three ways registerednurse-to-inpatient ratio, registered nurse-to-adjusted inpatient ratio, and nursing staff-to-adjusted inpatient ratio. Patient outcomesincluded length of stay, readmission within 30 days, psychiatric emergency treatment, use of injected psycholeptics for chemical restraint,and hypnotics use. Relationships between nurse staffing levels and patient outcomes were analyzed considering both patient and systemcharacteristics using multilevel modeling. @*Results@#Multilevel analyses revealed that more inpatients per registered nurse, adjusted inpatientsper registered nurse, and adjusted inpatients per nursing staff were associated with longer lengths of stay as well as a higher risk of readmission.More adjusted inpatients per registered nurse and adjusted inpatients per nursing staff were also associated with increased hypnoticsuse but a lower risk of psychiatric emergency treatment. Nurse staffing levels were not significantly associated with the use of injectedpsycholeptics for chemical restraint. @*Conclusion@#Lower nurse staffing levels are associated with negative health outcomes of psychiatricinpatients. Policies for improving nurse staffing toward an optimal level should be enacted to facilitate better outcomes for psychiatricinpatients in Korea.