title: Screening for depression in low-income elderly patients at the primary care level: use of the patient health questionnaire-2.
abstract: BACKGROUND
  Depression is one of the most common mental disorders and a leading cause of disability worldwide. It constitutes a serious public health problem, particularly among elderly individuals. Most depressed elderly patients are treated by primary care (PC) physicians. The "Patient Health Questionnaire" (PHQ-2) is an instrument used for the detection of depression in PC settings.
  
  
  OBJECTIVE
  Evaluate the performance of the PHQ-2 in a low-income and uneducated elderly PC population.
  
  
  METHODS
  A non-probabilistic population sample of 142 individuals was selected from the healthcare unit's users ≧ 60 years. Criterion validity was assessed by estimating the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the PHQ-2 in comparison with the structured interview using the DSM-IV. The estimates of sensitivity and specificity were obtained from varying cut-offs of the PHQ-2 score. A Receiver Operator Characteristic (ROC) curve was constructed and the area under the curve (AUC) was calculated.
  
  
  RESULTS
  The group was predominantly female (73.9%), with low education level (mean 3 years of schooling). The mean age was 72.5 years old. The prevalence of depression was 26.1%. The best values of sensitivity (0.74), specificity (0.77), PPV (0.50) e NPV (0.90) were obtained with score equal to 1. The AUC was 0.77, indicating a modest performance of the test accuracy.
  
  
  CONCLUSIONS
  The simplicity of the PHQ-2 is an advantage for its use in PC. The high NPV indicated that 90% of those who tested negative would not need additional tests. However, the low PPV indicated that the PHQ-2 is not sufficient to screen for depression. The application of the instrument could be the first step of the screening, that would include a second step to all those with positive tests formerly.
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Valéria Teresa Saraiva
authors.initials: VT
authors.lastname: Lino
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Margareth Crisóstomo
authors.initials: MC
authors.lastname: Portela
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Luiz Antônio Bastos
authors.initials: LA
authors.lastname: Camacho
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Soraya
authors.initials: S
authors.lastname: Atie
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Maria José Barbosa
authors.initials: MJ
authors.lastname: Lima
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Nádia Cristina Pinheiro
authors.initials: NC
authors.lastname: Rodrigues
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Mônica Bastos de Lima
authors.initials: MB
authors.lastname: Barros
authors.affiliation: National Public Health School/Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
authors.forename: Mônica Kramer de Noronha
authors.initials: MK
authors.lastname: Andrade
mesh_terms: D000368:Aged; D019540:Area Under Curve; D003863:Depression / Q000175:diagnosis*; D005260:Female; D015577:Geriatric Assessment; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011203:Poverty; D011237:Predictive Value of Tests; D011320:Primary Health Care; D011569:Psychiatric Status Rating Scales; D012372:ROC Curve; D011795:Surveys and Questionnaires