“So on a scale of 0-10 with 10 being worst pain imaginable and 0 being no pain where would you score your pain………….. just roughly…………. to give me an idea………. so that I’ve got a baseline…… maybe for the last week or so…… an average….. out of 10….. JUST GIVE ME A NUMBER!”
The latter part, I hope obviously, is soliloquy. But it conveys frustration felt by physios the world over. All I want is a number to write down so I can carry on with my assessment algorithm. The next step in the chain. But are we collecting data for its own sake? Do we have a purpose other than routine? How much do we gain from pseudo-quantification of a subjective phenomena? And how much do we lose?
On reflection I’ve always felt awkward trying to coerce someone to score their pain. Have you ever noticed how frustrated they can become? Pain is subjective. By its nature difficult to score. Which is why some won’t score no matter how hard you push, others clam up, many insist on 0.5 decimals, others score 11 out of 10! All indicators of discomfort with the process. And whilst I see its intended target (grasping severity) equally it can be dismissive of their experience.
It’s an odd concept. Consider asking people to score other subjective experiences out of 10. When your partner says they love you. (Or hate you!) When your dad says he is proud of you. When your friend tells you they hope to get a new job. When your child is sad because they are being bullied at school. How would each react to being asked to score these experiences? They’re describing a feeling, a subjective experience. By asking them to score this we may invalidate their experience. Open it to comparison. Some experiences become more valid than others. Intensity and quality are appropriate to measure but can be gained without numbers.
The subjective risks becoming a quantitative data collection process. That can be measured. That act as markers. There is a deep rooted attraction to objective, mathematical data. It is neat, concise and ‘accurate’. I always remember a lad I played footy with at Uni doing a Maths degree. He’d often get a mark of 100% in some of his modules! (I wonder how many University essays are marked at 100%) The hope with algorithm is that it’s mathematical, methodical and if you get things just right it’s 100% guaranteed. All you need is comprehensive data and a robot. Magic!
So can health be reduced to data? Can science be reduced to numbers? Can pain be reduced to a score? Of course some people can score pain without inner turmoil. But when we force a subject to be an object we lose something. In the same way if we force objective data into purely subjective. Imagine the difference between describing your favourite song, painting, game compared to actually seeing, hearing, experiencing or observing this in person. Hence “a picture paints a thousand words” (although even this is subject to interpretation). The danger of algorithm is that we force their story into numbers and measurements and miss powerful words and narrative. Allow them to paint a picture, not colour by numbers.
No calls should be made to abandon objective data. Rather gather it appropriately. It does ask questions of how we collect meaningful data. Can we capture qualitative outcome measures? We need in this age to show our impact. This is easier in number. We are also keen to distance ourselves from alternative therapies. This has pushed us away from non-numeric outcomes in order to be viewed “real” science. Our fear is that alternative therapies may produce positive data. Rightly so we should aim higher than this. But should we throw it out?
What about in science? The VAS (Visual Analogue Score) and NRS (Numeric Rating Score) are commonly used in research and has been shown reliable but no way of measuring pain accurately exists (construct validity). The pain experience then becomes ordinal data (or even interval/ratio). As a surrogate measure VAS may still has a role in research but clinically it is more questionable. Does using VAS make a better clinician?
Matt Dancigers blog challenges the purpose of outcomes nicely. Are outcomes patient centred or are they focused on the outcomes of the clinician or research funders? Are longterm health outcomes clinically more useful than immediate pain or function? Not to dismiss pain and function. These are often the reason for seeking intervention. But I wonder by stopping short of health (at pain and functional improvement) do our long term effects suffer?
Health is a vast and complex arena. Sometimes pain is easy to change. Immediate behaviour change often prompted by consciousness of pain plus an appropriate strategy. But overall health change is harder. It requires lifestyle change. When the prodding of the conscious dulls through a narrative of time or helplessness. Sometimes pain is difficult to change, should we focus on health instead? How much should we be looking for pain management strategies and how much for health management strategies?
So let us think. Think where an algorithm is going to get you. Are we looking for quick answers to robotic questions? Do we deal in singular thought processing or binary outcome (yes/no)? Unfortunately the subjective history is nuanced which doesn’t suit an algorithmic approach. Sorry robots.
Be more human. Be less robot
Thanks for getting this far.
I recognise there were more questions than answers with this blog. Would be great if you have a spare minute to head over to Facebook and like our page and engage in further discussion around VAS, outcome measures and algorithm. http://bit.ly/bemorehumanFB
Some helpful ideas from IRISS on qualitative outcomes http://bit.ly/qualoutcome
A nice piece in NEJM on why we use pain intensity score + why this hasn’t helped http://bit.ly/VASintensity
Estefan 1987 http://bit.ly/estefanrythm
A nice discussion and replies to article on limitation of VAS:
Kersten et al 2012. Discuss limitation of VAS http://bit.ly/VASinterval
Price et al 2012. Defend use of VAS as ratio data http://bit.ly/VASration
Franchignoni et al 2012. Discuss ontology and limit of VAS. http://bit.ly/VASontology