Flags of many colours

Just had a chance to read through Nicholas and colleagues' new paper "Early identification and management of psychological risk factors ('yellow flags') in patient with low back pain: a reappraisal" online first in Physical Therapy.  It is essentially a 'survey of the landscape' of the usefulness of 'yellow flags', and whether or not a representative sample of the literature suggests that risk factor-targeted interventions in fact improve outcomes.  This was not a systematic or critical review, so results are best taken with a grain of salt.  On balance the findings support the idea of psychological yellow flags, such as negative beliefs about pain, catastrophizing (which are conceptually pretty similar constructs), depression, and pain intensity (interesting that pain intensity is grouped in with psychological yellow flags) as being consistent risk factors of a poor outcome.  Further, there is enough evidence currently available to suggest that interventions tailored specifically towards addressing yellow flags, when provided by a competent and trained therapist, can positively affect outcome.  Fair enough, good information to know.

The real standout part of this paper though are the discussion around challenges in interpreting studies.  First of all, the authors start by addressing the nature of yellow flags as things like fears and negative beliefs.  They distinguish yellow flags from blue flags, black flags and orange flags, as outlined below.

Yellow flags:  psychological risk factors that are conceivably amenable to intervention from properly trained health professionals, but don't inherently require formal psychological intervention.

Orange flags:  Frank, diagnosable psychological disorders that require intervention from a mental health professional.

Blue flags:  Worker's perceptions of barriers to recovery at the workplace, such as beliefs that the workplace is stressful or the job is too demanding.

Black flags:  Observable environmental barriers to recovery, including the acutal nature of the work or workplace, or insurance and compensation system.

That in itself is a useful classification in my opinion.  Physios frequently ask me about the degree to which psychological screening and intervention fits within our scope.  Using this nomenclature, I could now conceivably answer by saying that, if trained properly, we could address yellow flags, but need to refer to the proper provider for orange flags.

One thing I find particularly interesting here, conspicuous in its absence especially considering this is published in a physical therapy journal, is that there is no 'flag' described for what I'll call biological/physiological risk factors.  The Aussie researchers are probably leading this charge, at least in the neck pain/whiplash area, identifying things like cold pain threshold, kinesthetic sensibility, pressure pain threshold (especially distally), motor control problems and the like.  Where do these risk factors fit into the system of 'flags'?  Perhaps they need their own colour.  Brown is leaping to my mind for some reason.  Thoughts?