..  docs/source/tasks/phq8.rst

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    Created by Rudolf Cardinal (rnc1001@cam.ac.uk).
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.. _phq8:

Patient Health Questionnaire 8-item depression scale (PHQ-8)
------------------------------------------------------------

History and guide
~~~~~~~~~~~~~~~~~

The PHQ-8 is the :ref:`PHQ-9 <phq9>` with the final question, about suicidal or
self-injurious thoughts, omitted (Kroenke et al. 2009, p165). It was omitted
for situations in which interviewers/data collectors are not able to provide
adequate intervention (Kroenke et al. 2009, p165). However, the omitted
question is "by far the least frequently endorsed" and the scoring is the same
as for the PHQ-9 (Kroenke et al. 2009, p165). The final prompt, about daily
functioning, is also omitted (Kroenke et al. 2009, p171).

A score of ≥10 is the standard cutoff for likely major depressive disorder
(MDD); this is the same cutoff as the PHQ-9 (Kroenke et al. 2010). A score of
≥10 has an 88% sensitivity and 88% specificity for major depression (Kroenke &
Spitzer 2002, via Kroenke et al. 2009).

- Kroenke K, Spitzer RL (2002).
  The PHQ-9: a new depression and diagnostic severity measure.
  *Psychiatric Annals* 32: 509–521.
  https://doi.org/10.3928/0048-5713-20020901-06

- Kroenke K, Strine TW, Spitzer RL, Williams JBW, Berry JT, Mokdad AH (2009).
  The PHQ-8 as a Measure of Current Depression in the General Population.
  *Journal of Affective Disorders* 114: 163–73.
  https://pubmed.ncbi.nlm.nih.gov/18752852/;
  https://doi.org/10.1016/j.jad.2008.06.026.

- Kroenke K, Spitzer RL, Williams JBW, Löwe B (2010).
  The Patient Health Questionnaire Somatic, Anxiety, and Depressive Symptom
  Scales: a systematic review.
  *Gen Hosp Psychiatry* 32: 345-59.
  https://pubmed.ncbi.nlm.nih.gov/20633738/


Source
~~~~~~

See :ref:`PHQ-9 <phq9>`, and Kroenke (2009) as above.


Intellectual property rights
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Public domain. See :ref:`PHQ-9 <phq9>`.