title: The 23-Hour Observation Unit Admissions Within the Emergency Service at a National Tertiary Psychiatric Hospital: Clarifying Clinical Profiles, Outcomes, and Predictors of Subsequent Hospitalization.
abstract: OBJECTIVE
  We examined health care utilization, clinical profiles (such as sociodemographic features, clinical severity), and outcomes (inpatient admission, revisit within 24 hours of discharge) of patients who were admitted to a 23-hour observation unit within the emergency service of a tertiary psychiatric hospital and hypothesized that a specific clinical profile (greater clinical severity, lower psychosocial functioning) predicted subsequent inpatient hospitalization.
  
  
  METHODS
  The medical records of all patients admitted to the observation unit from February 5, 2007, to February 4, 2012 (N = 2,158) were assessed for relevant data. Clinical severity and level of psychosocial functioning were assessed using Clinical Global Impressions-Severity (CGI-S) and Global Assessment of Functioning (GAF) scales, respectively.
  
  
  RESULTS
  Overall, the patients seen were predominantly Chinese males > 36 years old who had diagnoses including stress-related, anxiety, affective spectrum, and psychotic disorders. The clinical severity score (CGI-S) improved significantly following discharge from the observation unit (t 1,1848 = 23.316; P < .001). Logistic regression analyses revealed that self-referred (P = .001), older patients (P = .007) with past psychiatric history (P = .019), lower GAF scores (P = .025), and less improvement of CGI-S scores (P = .001) were associated with inpatient admission after a 23-hour stay in the observation unit.
  
  
  CONCLUSIONS
  Our study findings affirmed our hypothesis and supported the utility of the observation unit in monitoring the overall clinical status of patients, which was linked with subsequent inpatient admissions. Better management of these patients at the outpatient level can potentially decrease unnecessary hospitalization and reduce health care cost as well as illness burden on patients and caregivers.
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Daw San
authors.initials: DS
authors.lastname: San Thinn
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Carissa Nadia
authors.initials: CN
authors.lastname: Kuswanto
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Min Yi
authors.initials: MY
authors.lastname: Sum
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Suet Bin
authors.initials: SB
authors.lastname: Chai
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Hian Koh
authors.initials: HK
authors.lastname: Doris Sok
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Changqing
authors.initials: C
authors.lastname: Xu
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Alex Hsin
authors.initials: AH
authors.lastname: Chuan Su
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Somnath
authors.initials: S
authors.lastname: Sengupta
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Rajesh
authors.initials: R
authors.lastname: Jacob
authors.affiliation: Department of General Psychiatry, Institute of Mental Health, Singapore (Drs San San Thinn, Chai, Su, Sengupta, Jacob, and Sim and Mss Koh and Xu); and Research Division, Institute of Mental Health, Singapore (Mss Kuswanto and Sum).
authors.forename: Kang
authors.initials: K
authors.lastname: Sim