Red Flags, Yellow Flags, Blue Flags, Black Flags


This page was originally posted on September 21, 2006. It has been the most viewed page on this blog. Updated February 22, 2013.  

The other day a student asked me where the phrase “red flag” originated. He had also heard of yellow flags, and suspected that there were other colours of flags to indicate barriers to recovery. Well, we looked in various glossaries of medical and medical education terms, without success. So I e-mailed Dr. Shawn Thistle, and, sure enough, he helped. It is difficult to find where these terms originated (try Googling blue flags!) and Dr. Thistle thinks they may just be part of every doctor’s vocabulary. (Ever since I wrote the title above, I can’t get Dr. Seuss’s One fish two fish red fish blue fish out of my head.)


Red flags/clinical red flags (biomedical factors) ~
These help identify potentially serious conditions, and are often listed in practice guidelines. Here is a description from Chapter 13 of the
Clinical guidelines for chiropractic practice in Canada [Glenerin Guidelines]:
The main focus for the prevention of complications is the recognition of well-known and established indicators or “red flag” signs and symptoms which may require careful assessment and reassessment, changes in treatment plan, or other appropriate action, such as emergency care or referral to another health care specialist. Ignoring these “red flag” indicators increases the likelihood of patient harm. 

Yellow  flags/clinical yellow flags (psychological or behavioural factors/predictors) ~
These indicate psychosocial barriers to recovery. Here is a definition from

New Zealand acute low back pain guide: incorporating the Guide to assessing psychosocial yellow flags in acute low back pain:
Yellow Flags are factors that increase the risk of developing or perpetuating long-term disability and work loss associated with low back pain … Before proceeding to assess Psychosocial Yellow Flags it is important to differentiate between acute, recurrent and chronic presentations. Evidence suggests that treating chronic back pain as if it were a new episode of acute back pain can result in perpetuation of disability. 

Blue flags/occupational blue flags (social and economic factors) ~
These refer to conditions in the workplace that may inhibit recovery. Examples are
monotony, low degree of control, poor relationships or high work demands. 

Black flags/socio-occupational black flags (occupational factors) ~
These are also used for workplace issues, but refer to organizational issues such as financial reliance on disability benefits, workers’ compensation issues, or employer attitudes to the sick worker.


Helliwell PS, Taylor WJ. Repetitive strain injury. Postgrad Med J 2004;80(946):438-43.See An Approach to Diagnosis
Main CJ, Williams AC.  ABC of Psychological Medicine. Musculoskeletal pain. BMJ 2002;325(7363):534-7.

Click on the image below for The clinical flags approach to obstacles to recovery from back pain and aspects of assessment.

From:  Main CJ, Williams AC.  ABC of Psychological Medicine. Musculoskeletal pain. BMJ 2002 Sep 7;325(7363):534-7. PMC version

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Web Sites, Facebook, Twitter and LinkedIn ~ What I’m doing now

Hello, everyone out there ~
I haven’t been keeping this blog up to date but I am still very much involved in continuing health education and chiropractic. This is what I am doing now, and you can see the twitter feeds from this site ~

I am the Web editor for ICL and still have involvement with CACHE:


Twittering for chiropractic, continuing health education and fun

I maintain three Twitter accounts, one for CACHE/ACEMC, one for the Index to Chiropractic Literature, and one just for fun stuff I find on the Internet. You can follow them from any page on this blog (right and left sides of the screen) at

Index to Chiropractic Literature is on facebook!

Since mid-October 2010, ICL has had a facebook page, and as of mid-December, we have over 200 friends! These people live in Canada, the United States, Australia, the United Kingdom, Spain, India, Japan, Mexico and Singapore. If you would like to receive regular updates on what’s being added to the database or the Web site, click on one of the icons on this page and “friend” us.

Check out the page at   

The new Index to Chiropractic Literature (ICL)

In July 2009 we launched the latest version of ICL – There are many new features, including improvements to the search interface, an Open Access Library, links to RSS feeds for relevant journals, lots of help pages, and a blog. ICL is a high quality product developed and maintained by librarians, and it’s free!

To find out how to search the database and find all the resources on the site, please see the help pages (second menu item from the left). 

See how far we’ve come since 2001!


Complementary and Alternative Medicine Use Among Adults and Children: United States, 2007

nccam  According to a national survey, in the United States in 2007, 38% of adults and 12% of children used complementary and alternative medicine. The survey is posted on the Web site of NCCAM (National Center for Complementary and Alternative Medicine):   PDF version

This report presents selected estimates of complementary and alternative medicine (CAM) use among U.S. adults and children, using data from the 2007 National Health Interview Survey (NHIS), conducted by the Centers for Disease Control and Prevention’s (CDC) National Center for Health Statistics (NCHS).

Read the press releasePubMed abstract.

Neck Pain and the Decade of the Bone and Joint 2000–2010 – Open Access!

The special supplement published in Spine in February 2008 has been republished with permission elsewhere. The European Spine Journal has published the Bone and Joint Decade articles on neck pain as v. 17, Supplement 1. The great news is, the whole supplement is available on PubMed Central.

European Spine Journal Volume 17 (Suppl 1);  April 2008

From the Editorial Preface:
In this supplement of Spine [republished with permission in this supplement], the results of a unique project, The Bone and Joint Decade 2000–2010 Task Force on Neck Pain and Its Associated Disorders, is published. This multidisciplinary, international Task Force, which was formed in 2000, has consisted of an executive committee, a scientific secretariat, an advisory committee together with research associates and graduate students. These groups involved more than 50 people. Committee members were based in 9 countries and represented 14 different clinical and scientific disciplines. Moreover, the Task Force was affiliated with 8 universities and research institutes in 4 different countries. Eleven professional organizations have been non-financial sponsors. Thus, the Task Force represents a unique gathering of international expertise covering all relevant aspects related to neck pain and its associated disorders. The Task Force has made an impressive systematic review of the vast literature in this field and a best evidence synthesis, which has resulted in 21 chapters in this supplement.