The aim of this study was to validate the Patient Health Questionnaire-9 for major depressive disorder and the Generalized Anxiety Disorder Scale-7 for any anxiety disorder within a population of workers with long-term sickness absence from work. Participants were recruited in collaboration with the occupational health service. Workers on sickness absence between 4 and 26 weeks were asked to complete both the PHQ-9 and the GAD-7 and were then evaluated with the MINI-interview to assess DSM-IV disorders. Reliability (Cronbach’s) of the PHQ-9 was. 92 and of the GAD-7 it was. 94. Criterion validity was calculated in terms of sensitivity and specificity. For the PHQ-9 a cut-off value of 10 provided a sensitivity of. 86 and a specificity of. 78. For the GAD-7 a cut-off value of 9 provided a sensitivity of. 82 and a specificity of. 76. Based on Receiver Operating Characteristics (ROC) analysis, the area under the curve (AUC) for the PHQ-9 for major depressive disorder was. 90. The AUC for the GAD-7 for any anxiety disorder was. 85. In conclusion, both tests show good characteristics of reliability and criterion validity.