Scoring the PHQ-9
All of this comes from the MacArthur foundation website, from their Primary Care Toolkit. For the entire kit in PDF format, which is 44 pages -- these scoring guidelines are from page 18 -- go to their Toolkit page; you'll have to fill out a few boxes to register, free.
I've summarized the scoring system below. However, if you would like to see the Foundation's step-by-step guidelines on scoring and interpretation, take this link, look for the Next button in the upper right corner of the page, and click through the next several screens. You will come to instructions for scoring; and the official "scorecard". What follows here is a brief version of those steps:
If you want a "yes or no" diagnosis of depression
1. Question 2 must be answered Somewhat difficult or worse; so if it's Not difficult at all, you can stop there.
2. Question 1: there must be a More than half the days or Nearly every day answer for 1a or 1b. If not, you can stop.
3. Total symptoms:
- 2-4 symptoms checked More than half the days can be called mild or minor depression.
- 5 or more symptoms marked More than half the days is major depression.
If you want to use the PHQ-9 as a monitoring tool for repeat quantitative measures
Sum the total number of points for question number one as follows:
Not at all 0 Several days 1 > 1/2 the days 2 Nearly every day 3
- Greater than 20 is severe depression
- Treatment should result in a score less than 10 [by "remission criteria", should be <5 -- editorial comment]
- (alternative "eyeball score" in follow-up: no check marks in the right 2 columns)