predictive validity

Colour therapy…
With only a small proportion of the people experiencing acute low back pain becoming chronically disabled by their pain, a holy grail of sorts has been to quickly and effectively identify those who need additional help and those who don’t.

The ‘Psychosocial Yellow Flags’ initially developed in New Zealand by Kendall, Linton & Main (1999) provides a useful mnemonic for the factors that have been established as predicting longterm disability – but requires clinicians to be aware of the flags, and record them. Because the ‘Yellow Flags’ are not ‘objective’ and can’t be summed or scored, there is no way to determine a cut-off point to identify those people only just at risk – and the tendency is to under-estimate those who need more assistance, while many clinicians report that they don’t feel comfortable or confident to assess ‘Yellow Flags’ in a primary health setting.

For those who can’t remember, the risk factors known to be associated with ongoing disability in people with acute low back pain are:

A: Attitudes and beliefs – e.g. catastrophising, a passive approach to rehabilitation, ‘Doctor fix me’, hurt = harm

B: Behaviours – e.g. resting for extended periods, poor sleep, using aids and appliances such as crutches or braces, inappropriate use of medication, self medication

C: Compensation – e.g. difficulty obtaining cover, inadequate or ineffective case management, multiple claims in the past, poor knowledge of what is available for assistance

D: Diagnosis/Doctor or treatment provider effects – unexplained technical language that is misunderstood, multiple diagnoses, multiple investigations, multiple ineffective treatments, assuring a ‘techno-fix’ is available, recommending changing jobs or stopping jobs

E: Emotions – anger, depression, sense of helplessness or feeling out of control, numbed emotions

F: Family and friends – unintentionally reinforcing pain behaviour, unsupportive of returning to work, punishing responses, or being socially isolated

W: Work – an employer who is unsupportive, history of frequent job changes or limited employment history, heavy manual work, monotonous work, high responsibility with limited control, shiftwork, working alone or while isolated, disliking the job

As I mentioned, these factors are well-known, and relatively easily recognised. Many people say to me that they have an intuitive ‘feel’ for those who will have trouble recovering from ALBP – but feel that if they ask about these factors, they risk ”opening Pandora’s box’, or being unable to extricate themselves from a complex or emotionally charged situation. Many people don’t feel adequately skilled in managing the issues involved, and would prefer to either let well enough alone, or quickly refer to someone else (Crawford, Ryan & Shipton, 2007).

Well, I don’t agree with any of those options. Although sometimes people will have ‘saved up’ a lot of their concerns and want to offload with a lot of emotion, for many people it’s a simple case of exploring what their concerns are and problem-solving around the practical issues. A referral to a psychologist or counsellor isn’t always necessary, and can for some people escalate their distress and disability.

What skills can you use to identify and manage ‘Yellow Flags’?

Open-ended questions like ‘How do you feel about your recovery so far?’, ‘Are there any things that concern you about your recovery?’, ‘What do you think is going on in your back?’, ‘What do you think this [diagnosis] means for you?’

Reflective listening demonstrates two things: (1) that you are listening and (2) that you want to understand. It should be used whenever someone begins to display emotional responses. Reflective listening can be simple ‘So from what you’ve said, I think you mean….’, or more complex ‘It seems that you think your boss wants you to go back to full duties and you’re not sure you can. I wonder if you’re feeling really anxious?’ When in doubt, reflect!

Action and responsibility – Then it can be really useful to pose this question: ‘So where does this leave you?’ or ‘What do you think you need to have happen next?’

For many people the step of demonstrating your acceptance of their point of view and understanding their distress is a good start. And many ‘Yellow Flags’ can be simply influenced by the person themselves – just being given permission to think of a solution that they’re ready to do, or being asked whether they want to hear of other options allows the person to feel more in control.

And for slightly more complex situations – such as financial strain from time off work, or difficulty within a relationship because of changed roles – these can be helped by budgetting advice, bringing the partner in to the clinic to be a part of the rehabilitation, or asking the person to think of community-based self-help organisations. Intense psychological therapy isn’t always necessary, and if misguided or not consistent with other messages about engaging in activity despite pain, can impede recovery.

And if you’re REALLY pressed for time, but still want to ‘pick winners and losers’ – a study by Westman, Linton, Ohrvik, Wahle´& Leppert (2007) finds support for the use of the ‘Orebro Musculoskeletal Pain Screening Questionnaire’, which is a 25 item questionnaire covering five groups (function, pain, psychological factors, fear avoidance, and miscellaneous which includes things like sick leave, age, gender, nationality, monotonous or heavy work and job satisfaction. It’s been used extensively in New Zealand in a compensation setting since 1999, as a screening tool to identify those who may be at increased risk of ongoing disability. This study reviews its use in sub-acute pain, with a three-year follow-up to identify the predictive validity of the instrument for sick leave.

The results are very strong – psychosocial factors as measured by OMPSQ were related to work disability and perceived health even 3 years after treatment in primary care. The screening questionnaire had discriminative power even for patients with non-acute or recurrent pain problems. The OMPSQ had better predictive power than any of the questionnaires included in the study, which included the Job Strain, the Coping Strategies Questionnaire (CSQ),
the Pain Catastrophizing Scale (PCS) and the Tampa Scale for Kinesiophobia (TSK). This study shows that among the factors, pain and function are the factors most strongly related to sick leave 3 years later.

Interestingly for me, the study demonstrated that function with focus on daily living, sleep capacity and pain experience had the most powerful predictive value concerning sick leave at 3 years. While earlier studies have shown that emotional and cognitive variables such as distress and fear avoidance beliefs have been strong predictors for 6–12-month outcomes, the best predictor in this study is having problems functioning.

The authors suggest that this probably reflects the length of the follow-up and suggests that different variables may be predictive at various stages in the process of chronification. Even though it is recognized that psychological variables are
influential factors, little is known about how and when these variables interact in the process toward disability.
Furthermore, psychological variables might operate differently for different people and at different time points.

So, this particular instrument, which has been widely used at least within New Zealand for many years, is readily available and gives clinicians and others very useful guidance on who might benefit the most from high intensity therapeutic input early.

WESTMAN, A. (2007). Do psychosocial factors predict disability and health at a 3-year follow-up for patients with non-acute musculoskeletal pain A validation of the Orebro Musculoskeletal Pain Screening Questionnaire. European Journal of Pain DOI: 10.1016/j.ejpain.2007.10.007

Crawford C, Ryan K, Shipton E (2007) Exploring general practitioner identification and management of psychosocial Yellow Flags in acute low back pain, New Zealand medical journal, 120:1254, pp U2536