title: The Adjustment Disorder--New Module 20 as a Screening Instrument: Cluster Analysis and Cut-off Values.
abstract: Adjustment disorder (AjD) is a transient mental health condition emerging after stressful life events. Its diagnostic criteria have recently been under revision which led to the development of the Adjustment Disorder--New Module 20 (ADNM-20) as a self-report assessment.
  
  
  
  To identify a threshold value for people at high risk for AjD.
  
  
  
  As part of a randomized controlled trial evaluating a self-help manual for burglary victims, the baseline data of all participants (n=80) were analyzed. Besides the ADNM-20, participants answered self-report questionnaires regarding the external variables post-traumatic stress disorder symptomatology, depression, anxiety, and stress levels. We used cluster analysis and ROC analysis to identify the most appropriate cut-off value.
  
  
  
  The cluster analysis identified three different subgroups. They differed in their level of AjD symptomatology from low to high symptom severity. The same pattern of impairment was found for the external variables. The ROC analysis testing the ADNM-20 sum scoreagainst the theory-based diagnostic algorithm, revealed an optimal cut-off score at 47.5 to distinguish between people at high risk for AjD and people at low risk.
  
  
  
  The ADNM-20 distinguishes between people with low, moderate, and high symptomatology. The recommendation for a cut-off score at 47.5 facilitates the use of the ADNM-20 in research and practice.
authors.affiliation: Department of Psychology, Division of Psychopathology and Clinical Intervention, University of Zurich, Zurich, Switzerland. l.lorenz@psychologie.uzh.ch.
authors.forename: L
authors.initials: L
authors.lastname: Lorenz
authors.affiliation: Department of Psychology, Division of Psychopathology and Clinical Intervention, University of Zurich, Zurich, Switzerland.
authors.forename: R C
authors.initials: RC
authors.lastname: Bachem
authors.affiliation: Department of Psychology, Division of Psychopathology and Clinical Intervention, University of Zurich, Zurich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Maercker
mesh_terms: D000275:Adjustment Disorders / Q000175:diagnosis* / Q000209:etiology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001007:Anxiety / Q000523:psychology; D016000:Cluster Analysis; D003863:Depression / Q000523:psychology; D005260:Female; D006801:Humans; D008016:Life Change Events; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D016032:Randomized Controlled Trials as Topic; D012720:Severity of Illness Index; D013313:Stress Disorders, Post-Traumatic / Q000523:psychology; D013315:Stress, Psychological / Q000523:psychology*; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Adjustment disorder; Diagnosis; Symptom assessment; Trauma and stressor related disorders