Reconciling uncertainty and the drive to diagnose

Recently it was suggested to me that even though I’m an occupational therapist, I might “diagnose”. Not so much diagnose disease, but “determine if a patient is depressed, anxious, catastrophising, fear avoidant etc?” The author goes on to say “isn’t that diagnosis too?” The comment was made in the context of a lengthy Twitter discussion about so-called “non-specific” low back pain. Over the course of I think about five weeks now, a large number of highly educated, erudite and passionate clinicians have argued the toss about whether it’s possible to identify the “cause” of nonspecific low back pain. On the odd occasion I’ve put my oar in to mention psychosocial aspects and that people seek help for many reasons, one of which may be pain intensity, but mostly people ask for help because either the pain is interfering with being able to do things, or because the person interprets their pain as an indication, perhaps, of something nasty.

I mention this context, because over the many tweets, I was struck by the degree of certainty demanded by various commentators on both sides of the discussion. “Where’s the gold standard?”; “What’s the evidence”; “Yes”; “No” – and in many respects, diagnosis is a practice based on degrees of certainty. You either have a disease – or you don’t. You have the signs and symptoms – or you don’t. Unless, of course, it’s the creeping edge of “pre-diagnosis” like my “pre-diabetes”.

In October I wrote about clinical enquiry, which is described by Engebretsen and colleagues (2015) as a complicated process (sure is!) of 4 overlapping, intertwined phases: (a) data collection – of self reported sensations, observations, otherwise known as “something is wrong and needs explaining”; (b) data interpreting “what might this mean?” by synthesising the data and working to recognise possible answers, or understanding; (c) weighing up alternative interpretations by judging; and (d) deciding what to do next, “what is the right thing to do”, or deliberation.

For, irrespective of our certainty about the precision of any particular test or ultimately a diagnosis, all of our work involves two people who must collaborate to follow the process outlined by Engebretsen and colleagues. That is, the person seeking help notices “something is wrong and needs explaining”, he or she communicates selected information to a knowledgeable person (a clinician) and that clinician will typically seek more information, and assemble this in some way (synthesise). In my case I like to do this assemblage in collaboration with the person so we can weigh up or judge various interpretations of that data. I bring some knowledge from my training and ongoing learning, while the person brings his or her intimate knowledge of what it is like to be experiencing that “something is wrong.” There are times when we are both in the dark and we need to collect some more information: for while the person knows what it is like to be in this predicament, there are likely factors not yet incorporated (or noticed) into the picture. For example, guided discovery or Socratic questioning usually involves exploring something the person is aware of but hadn’t considered relevant, or hadn’t joined the dots. I don’t think it takes rocket science to see just how messy and complex this communication and information synthesising process can be – it only takes a person to fail to provide a piece of information (because they don’t think it’s relevant) for the analysis to go awry.

I like the depiction of the diagnostic process described in Britannica.com because throughout the process, the diagnosis is held lightly. It’s provisional. The process of diagnosing is seen as a series of hypotheses that are tested as the treatment progresses. In other words, despite beginning treatment, clinicians are constantly testing the adequacy and accuracy of their clinical reasoning, being ready to change tack should the outcome not quite stack up.

As a clinician and commentator who focuses on the relationship between people with pain and the clinicians they see, it strikes me yet again that the process of diagnosis is often one of relative uncertainty. While it’s pretty easy to determine that a bone is fractured, when pain is the presenting problem and because imaging cannot show pain (and when there are few other clear-cut signs), the clinical reasoning process is far more uncertain.

As I would expect, I’m not the first person to ponder the certainty and uncertainty dilemma in diagnosis. Some of my favourite authors, Kersti Malterud and colleagues (and especially Anne-Marie Jutel!) wrote an editorial for the British Journal of General Practice in which they argue that uncertainty, far from being “the new Achilles heel of general practice (Jones, 2016), instead is absolutely typical of the complexity involved in general practice diagnostic work. They go on to say “The nature of clinical knowledge rests on interpretation and judgment of bits and pieces of information which will always be partial and situated. In this commentary, we argue that the quality of diagnosis in general practice is compromised by believing that uncertainty can, and should, be eliminated.” (p. 244).

In their editorial, Malterud and colleagues point out that the person’s story is essential for diagnosis – and that people have all sorts of reasons for not disclosing everything a clinician might want to know. One of those reasons may well be the clinician’s capability for demonstrating willingness to listen. They also argue that models of disease are social and therefore dynamic (ie what we consider to be disease shifts – pre-diabetes is a good example). People who don’t fit the received model of “what a symptom should be” may not be heard (think of women with heart disease may not present in the same way as men), while those with “medically unexplained” problems just do not fit a disease model.

They make the point that clinicians need to recognise that clinical testing “does not eliminate uncertainty, rather the opposite as it introduces false positive and negative results.” For my money, diagnostic testing should only be used if, as a result of that diagnosis, clinical management will change – and just to add another dollop of my opinion, I’d rather avoid testing if not only does clinical management not change, but outcomes are no different!

I think the call for certainty emerges from what Malterud and co describe as “The rationalist tradition” which “seeks to provide a world of apparent security where certainty is readily achievable.” The problems of both low back pain and many types of mental illness demonstrate very clearly that knowledge allowing us to be certain only covers a tiny amount of the territory of ill health. There is more unknown and uncertain than certain.

I’ll end with this quote from Malterud and co’s paper “Clinical practice must therefore develop and rely on epistemological rules beyond prediction and accuracy, acknowledging uncertainty as an important feature of knowledge and decision making. Nowotny (2016) suggests the notion ‘cunning of uncertainty’ as a strategy where we get to know uncertainty and acquire the skills to live with it.” In occupational therapy practice, uncertainty is always present in our problem-solving process – and consequently I don’t “diagnose”. I never know the effect of a tendency to “think the worst” or “worry” or “avoid because I’m scared” – the constructs it was suggested that I “diagnose”. Firstly because while I might recognise a pattern or tendency – I don’t know when, where, how or why the person may do that thing. And context, purpose, motivation and response all matter when it comes to people and what they do. And secondly, diagnosing suggests that we have a clear and specific approach to treat – and in most of my clinical work, certainty around outcome is definitely not a thing. We never really know if our suggestions are “right” because most of the impact of what we suggest is on the person within his or her own life. In my practice the outcomes ultimately determine how well I’ve worked with someone. Perhaps NSLBP is another of these human predicaments where being certain is less advantageous than embracing uncertainty and an unfolding narrative in someone’s life.

Engebretsen, E., Vøllestad, N. K., Wahl, A. K., Robinson, H. S., & Heggen, K. (2015). Unpacking the process of interpretation in evidence‐based decision making. Journal of Evaluation in Clinical Practice, 21(3), 529-531.

Malterud, K., Guassora, A. D., Reventlow, S., & Jutel, A. (2017). Embracing uncertainty to advance diagnosis in general practice. British Journal of General Practice, 67(659), 244-245. doi:10.3399/bjgp17X690941

Nowotny H. The cunning of uncertainty. Cambridge: Polity Press, 2016