Pain disorder (PD), as referenced in the
DSM‐IV‐TR
, “is characterized by pain that is the predominant focus in the clinical presentation and is of sufficient severity to warrant clinical attention. In addition, psychological factors are judged to play an important role in pain's onset, severity, exacerbation, or maintenance.” Some authors voiced concerns and criticisms regarding the
DSM‐IV
criteria for PD; specifically, that they are too broad, diagnostically unreliable, and therefore rarely used in clinical practice or research. With
DSM‐5
, PD was no longer listed as a separate diagnostic entity but was designated as a specifier (i.e., for people whose somatic symptoms predominantly involve pain) in the category of somatic symptom disorder (SSD). Although there is a paucity of well‐controlled treatment studies, extant research implicates a number of psychological, behavioral, neuropsychological, and physiological factors in the genesis of PD.