The PHQ was originally developed to detect 5 disorders, the depression, anxiety, and somatoform modules (in that order) have turned out to be the most popular.
The PHQ-SADS was developed to reflect that most primary-care patients with depressive or anxiety disorders present with somatic complaints; the co-occurrence of somatic, anxiety, and depressive symptoms (the SAD triad) is exceptionally common.
The PHQ-SADS includes PHQ-9, GAD-7, and PHQ-15 as well as panic symptoms for PHQ.
The PHQ-SADS was developed by Robert L. Spitzer, MD, and colleagues.