title: Validation of the PHQ-9 as a screening instrument for depression in diabetes patients in specialized outpatient clinics.
abstract: BACKGROUND
  For the treatment of depression in diabetes patients, it is important that depression is recognized at an early stage. A screening method for depression is the patient health questionnaire (PHQ-9). The aim of this study is to validate the 9-item Patient Health Questionnaire (PHQ-9) as a screening instrument for depression in diabetes patients in outpatient clinics.
  
  
  METHODS
  197 diabetes patients from outpatient clinics in the Netherlands filled in the PHQ-9. Within 2 weeks they were approached for an interview with the Mini Neuropsychiatric Interview. DSM-IV diagnoses of Major Depressive Disorder (MDD) were the criterion for which the sensitivity, specificity, positive- and negative predictive values and Receiver Operator Curves (ROC) for the PHQ-9 were calculated.
  
  
  RESULTS
  The cut-off point of a summed score of 12 on the PHQ-9 resulted in a sensitivity of 75.7% and a specificity of 80.0%. Predictive values for negative and positive test results were respectively 93.4% and 46.7%. The ROC showed an area under the curve of 0.77.
  
  
  CONCLUSIONS
  The PHQ-9 proved to be an efficient and well-received screening instrument for MDD in this sample of diabetes patients in a specialized outpatient clinic. The higher cut-off point of 12 that was needed and somewhat lower sensitivity than had been reported elsewhere may be due to the fact that the patients from a specialized diabetes clinic have more severe pathology and more complications, which could be recognized by the PHQ-9 as depression symptoms, while instead being diabetes symptoms.
authors: Department of Diagnostics and Treatment of Common Mental Disorders, Trimbos-Institute, PO Box 725, 3500 AS Utrecht, the Netherlands. Ksteenbergen@trimbos.nl
authors: Kirsten M
authors: KM
authors: van Steenbergen-Weijenburg
authors: Lars
authors: L
authors: de Vroege
authors: Robert R
authors: RR
authors: Ploeger
authors: Jan W
authors: JW
authors: Brals
authors: Martijn G
authors: MG
authors: Vloedbeld
authors: Thiemo F
authors: TF
authors: Veneman
authors: Leona
authors: L
authors: Hakkaart-van Roijen
authors: Frans F J
authors: FF
authors: Rutten
authors: Aartjan T F
authors: AT
authors: Beekman
authors: Christina M
authors: CM
authors: van der Feltz-Cornelis
mesh_terms: D000368:Aged; D000554:Ambulatory Care Facilities; D003865:Major Depressive Disorder / Q000150:complications / Q000175:diagnosis*; D048909:Diabetes Complications; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D008403:Mass Screening / Q000295:instrumentation*; D008875:Middle Aged; D009426:Netherlands