In a study that compared the accuracy of somatic vs non-somatic items in diagnosing depression in cancer patients, the best diagnostic performance was achieved by the non-somatic items. Researchers analyzed the routine data of 4,705 patients and examined the diagnostic accuracy of somatic vs cognitive-emotional PHQ-9 items. For the single PHQ-9 items, receiver operating characteristics, sensitivity, specificity, positive, and negative predictive values were applied for the diagnoses on major depressive disorder (MDD) and any depressive disorder (ADD). They found:
- Major depression was found in 11.1% of the study population.
- The non-somatic items played a key role in the diagnosis of MDD, whereas the accuracy of the somatic items increased in the diagnosis of ADD.
- For both MDD and ADD, the best performance was achieved by the non-somatic items “little interest” and “feeling down”.
Grapp M, Terhoeven V, Nikendei C, et al. Screening for depression in cancer patients using the PHQ-9: The accuracy of somatic compared to non-somatic items. [Published online ahead of print May 13, 2019]. J Affect Dis. doi:10.1016/j.jad.2019.05.026.