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Red alert

How useful are flags for identifying the origins of pain and barriers to rehabilitation? Allison Carvalho investigates

A patient who says she has excruciating lower back pain is standing in your consultation room. She winces with discomfort as you examine the affected area. But she walks well and regularly plays tennis. You wonder: how much of her pain is musculoskeletal? Could it be psychological? Are work conditions causing the problem? Or is her perception of the pain colouring her experience of it? You need some answers. Enter flags.

Flags are markers of risk factors in musculoskeletal disorders. There are currently five: red, yellow, orange, blue and black. They aim to help physios identify the risk of disability in patients and pinpoint appropriate interventions to prevent it. They also aim to assess how potential barriers to rehabilitation may be managed.

Red flags, introduced in the UK and the US in 1994, concern signs of serious pathology in patients with lower back pain that require urgent surgical opinion.

Yellow flags, developed in New Zealand in 1997, indicate psychosocial factors such as depression and the patient's beliefs about their condition.

Blue flags, introduced in 2000, relate to an individual's perception of work.  The black flag, also introduced in 2000, denotes work conditions that could inhibit rehabilitation, such as a job requiring heavy lifting or the wrong height of desk in a fixed work station.

 Orange flags, introduced in 2005, signal abnormal psychological processes or drug abuse. They indicate referral to a specialist is required.

'The concept of red, yellow and blue flags has become more widely accepted over the last five years,'  says Dr Paul Watson, senior lecturer in pain management and rehabilitation at the University of Leicester. 'This was mainly because of the broader acceptance of the biopsychosocial model.'

The biopsychosocial model proposes that biological, psychological and social factors all affect the way people function. It looks at the patient's mind and body as two interlinked systems.

'Once you accept this model as relevant to musculoskeletal pain you have to start looking more broadly at the physiotherapy assessment, and this is where yellow and blue flags in particular become important, ' says Dr Watson.

Yellow flags cover mainly psychosocial barriers. Other barriers are external to the individual but still prevent rehabilitation. These are the 'system' – access to treatment, the attitude of employers to helping people back into work, the appropriateness of treatment given, the sickness certification system and the availability of graded return to work, he adds.


The potential of flags in managing musculoskeletal problems will be discussed at a conference at Keele University on 20 September. Speakers at the conference, entitled The Decade of the Flags, will include several of those who originated the flags system.

Chris Main, professor of clinical psychology (pain management)  at  Keele University,  and chair of the conference, was involved in the development of yellow flags for  use in New Zealand in 1997, when treatment costs following accidents were spiralling out of control.

 'Legislation there at that time permitted unlimited access to treatment for patients who had back injuries because of an accident. Unfortunately, the rate at which new patients presented for treatment exceeded the rate at which they were being discharged after treatment. Costs for New Zealand's Accident Compensation Corporation were spiralling out of control,' he says.

Working with clinical psychologists, Nick Kendall and Steven Linton, Professor Main  devised the yellow flags system for the early identification and management of patients with lower back pain for the ACC.  'The yellow flags were mainly clinical rather than occupational and focused primarily on the predictors of chronicity,' he says.

Yellow flags comprise a system for structured interviewing, a psychometric screening tool and guidelines for early pain management.

With  Kim Burton, director of the spinal research unit at the University of Huddersfield,  Professor Main then went on to develop blue flags.  These focus on the patient's perceptions of work. He was also involved in the development of orange flags in 2005.

How effective are flags in the assessment of patients?.  Professor Main says: 'I suspect flags are well known to many physios, yet used systematically by very few.'

He believes the use of yellow flags, in particular, 'is often unsystematic and inconsistent, partly because there is little specific focus on their nature and use in traditional physiotherapy training'.

MISUSE Dr Watson also notes the misuse of yellow flags: 'There are still physios who think the identification of any psychosocial factors associated with back pain is a reason to deny treatment or refer to the local pain clinic, he says. 'This is utterly wrong.' Physios could, in effect, treat many of the patients they mistakenly refer to pain clinics, he believes.

'A  range of health professionals, including physios, have referred patients to me in tertiary care with a “diagnosis” of psychosocial back pain, yellow flags back pain and even psychic back pain,' he says.

'People sometime use the flags to label rather than intervene appropriately. Most of these patients could have been adequately managed by an appropriately trained physio in a department or primary care.'

But Ross Wilkie, physiotherapy research fellow at Keele University, says that properly used, flags are a valuable assessment tool, encouraging a broad  approach,  'The flags system provides physios with a framework, and in best practice should be adhered to,' he says.

'As a bare minimum red flags must be acknowledged in the notes.  This indicates  contraindications to many physiotherapy interventions,' he adds.

For a comprehensive biopscyhosocial assessment, other flags should also be acknowledged in notes. 'For example, patients may not respond to physiotherapy or return to function because of depression (yellow flag),' he adds.

 'Don't just treat the pathology or signs of symptoms such as pain and stiffness, but look at the identified psychosocial risk factors that play a major role in the recovery from musculoskeletal conditions too, ' urges Dr Wilkie.

'Blue and black flags should highlight to physios the importance of psychological aspects of managing patients with work-related conditions in the workplace. Physios need to know the relevance of these for their work with anyone in the workplace,' he adds.

Dr Watson echoes the importance of considering psychological factors: 'In the beginning, I think there was an erroneous belief that this was the realm of the psychologist. It's not. Physios, like it or not, are the key healthcare professionals in the management of this problem. They have the correct musculoskeletal training and clinical experience and they're usually patient-centred. I think this is filtering through the profession and that's how it should be'


Professor Main and Dr Watson believe it is not advisable to  introduce more colours until the current flags are fully understood.

Dr Watson says: 'We're still in the infancy of good targeting of treatment. Screening tools need to be relatively brief or physios won't use them.

Patients' ideas about back pain may be influenced by health professionals who either reinforce, or fail to address them, he adds.  These beliefs are mainly about harming the back and the severity of their condition, or their suitability for work.

Overall, he believes, much better understanding of the flags and a clear dialogue between patient and physio are central to first-class management of musculoskeletal problems.

'We desperately need to look at the interaction between patient and therapist in consultation and during treatment,' says Dr Watson . 'I believe that this is as important, if not more important, than the actual content of a pain management programme.' FL

Flags and their implications

Flag  Action

Red Triage for specialist medical opinion

Reassess if appropriate

Orange Triage to mental health specialist

Reassess after specialist treatment

Yellow Biopsychosocial management

Develop integrated approach to reactivation with   removal of pereived obstacles to recovery

Blue  Identify modifiable work perceptions

Develop integrated approach to reactivation

Consider liaison with employer in context of return to   work or work retention plan    Black  Appraise significance as potential rehabilitation     'showstoppers'

Check black flags with employer and investigate possibility of accommodation Reset patient expectations and develop integrated approach to reactivation OR do not accept for treatment


The Decade of the Flags conference will be held at Keele University on 20 September 2007.

Main C, Sullivan M, Watson P. Pain Management: Practical Applications of the Biopsychosocial Approach in Clinical and Occupational Settings Oxford: ElseverHealth Sciences.


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