title: Hospital Anxiety and Depression Scale: a study on the validation of the criteria and reliability on preoperative patients.
abstract: OBJECTIVE
  A few studies have shown that patients are frequently under strong distress in the preoperative period. The Hospital Anxiety and Depression Scale (HADS) is an instrument used to evaluate anxiety and depression. The aim of this study was to evaluate the validity of the criteria and reliability of the Hospital Anxiety and Depression Scale (HADS) in preoperative patients.
  
  
  METHODS
  Seventy-nine patients admitted to the Surgery Department of Santa Casa de Misericórdia de São Paulo where evaluated, while the control group was composed of 56 companions. The following tools were applied: Demographics data questionnaire, Beck Anxiety and Depression Inventory, and HADS.
  
  
  RESULTS
  HADS internal consistency ranged from 0.79 to 0.84. The items of HADS demonstrated a positive correlation with the total score of the relating subscales. Spearman correlation between HADS-A and Beck Anxiety Inventory (BAI), and between HADS-D and Beck Depression Inventory (BDI) ranged from 0.6 to 0.7. The sensitivity and specificity ranged from 69.6% and 90.9%.
  
  
  CONCLUSIONS
  The subscales of HADS showed internal consistency indices recommended for screening tools. The items in HADS demonstrated a positive correlation with the total score of the anxiety and depression subscales. The moderate to strong correlation demonstrated for HADS-A and HADS-D may be related to the comorbidity between anxiety and depression. For the physician who uses HADS, the thought that anxiety and depression are separate concepts is still useful. The use of a simple tool, such as HADS, could reveal mood changes that can go unnoticed by the supporting team.
authors.affiliation: Hospital Central da Irmandade da Santa Casa de Misericórdia de São Paulo (HC-ISCMSP), São Paulo, SP. alvaromarcolino@uol.com.br
authors.forename: José Alvaro Marques
authors.initials: JA
authors.lastname: Marcolino
authors.forename: Ligia Andrade da Silva Telles
authors.initials: LA
authors.lastname: Mathias
authors.forename: Luiz
authors.initials: L
authors.lastname: Piccinini Filho
authors.forename: Alvaro Antônio
authors.initials: AA
authors.lastname: Guaratini
authors.forename: Fernando Mikio
authors.initials: FM
authors.lastname: Suzuki
authors.forename: Luís Augusto Cunha
authors.initials: LA
authors.lastname: Alli