Friday, July 25, 2008

Bang for Your Buck

A new MRI machine was installed in St. Paul's Hospital this month. While this latest-generation scanner will add new diagnostic capabilities, its main task is to add diagnostic capacity. That is, it may have some new tricks, but mainly it's going to be doing much more of the same old tricks. Not that that's a bad thing.

Or is it?

A paper in the latest Canadian Association of Radiologists Journal reviewed CT/MRI scan use in Ontario. The authors looked at the stated indications for the examination, and correlated it with the final report (normal/indeterminate/abnormal). Any conclusions are limited by the retrospective, chart-abstraction design of the study, and the authors are careful to point this out. However, some findings should lead to further study.

"Less than 2% of CT scans of the brain for headache found abnormalities that could explain the headache." That's a lot of normal CT scans (which, aside from utilization issues, are not completely risk-free). The authors point out that a negative CT scan may still be valuable to reassure the patient, but also wonder whether the same reassurance may come from a frank discussion between physician and patient about the (un)likelihood that the CT scan will show any significant abnormality.

Headache was the stated indication for 26.8% of outpatient brain CTs, so reducing this demand for service could have a significant impact on access to scans.

It sometimes seems more expedient to use the "brute force" approach of adding capacity (more MRI/CT scanners) to manage queues, rather than looking at managing demand (are the tests being ordered appropriately?). I've griped about this before in a different context, namely the CMA's "Help Wanted" campaign to expand the physician pool.

Which brings me to our latest attempts to manage demand in our office. We started thinking about the frequency of internal demand (urologists recalling a patient for review) last fall. I posted some initial data in April. When I circulated the early results on how frequently each urologist was asking for patients to be recalled, my partners told me that the data was confusing and it wasn't clear what it indicated. So, we've continued to collect the data, and tried to show it in a more useful format.

Wow! That's a lot of variation. Some docs hardly recall any patients at all. Some recall a lot of patients on an annual basis (yellow bars) and some are recalling patients every 3 months (blue bars).

But, this first chart we generated is somewhat misleading. It's showing the number of patients recalled and doesn't account for the total number of patients seen by each urologist. We need to look at the recall rate (number of recalls/total number of patients). This will also level the playing field between part-time (lower volume) and full-time practitioners.

For example, in the first graph, Doctor C looked to be generating relatively little internal demand. However, the recall ratio in the second graph shows Doctor C to be generating a high rate of internal demand.

This doesn't tell us who is practising correctly or incorrectly, or even where changes should happen. But, it does show us the wide variation in our recall practices and give us a starting point for discussion.

When the urologists initially reviewed these results, several comments rationalized the variation in practice. One doc explained that his patient population was unique and required frequent recall. Another felt that, as he has been in practice for longer than some other partners, he has accumulated more patients with chronic conditions requiring regular review.

These are valid points. There may be significant reasons for the variation we see here. However, there must be some room to learn from each other's practices. What are Doctors A and D doing that their recall rate is so much lower than the others? (Of course, inquiring into that might yield surprising results… Maybe they need to be recalling more patients!)

For now, we're posting these charts to raise awareness of each urologist's recall rates. I'm going to explore the practices of the low-recall docs, rather than critique the higher-recall docs.

While it's true that managing internal demand by reducing recall rates will improve wait times, we don't want to sacrifice high-quality care for expediency. I think that changing recall behavior will be a delicate task. This is the first time that Advanced Access has challenged us to change the quality, rather than just quantity (i.e. working down the backlog) of our practices.


  1. Originally posted by Steven Lewis, (Access Consulting) 07/29/08 10:20 AM

    Kishore, as you know you're closing in on sacred and treacherous territory: clinical autonomy, assumptions about more is better, intended and unwitting supply-induced demand, etc. It's interesting that it is instinctively much less threatening to explore the possibility of underutilization (the very low callback-oriented urologists) than overutilization (potentially all or most of the rest). As you say, despite endless volumes of research we do not have defensible benchmarks for appropriate, population-based utilization rates based on transparent and sensible criteria, be they about diagnostic imaging or specialist consultations. At the core of much of this is anxiety - on the part of both providers and users of care - about two phenomena: certainty, and delayed detection of a treatable problem. It would be intriguing to ask your colleagues about their "yield thresholds" and other expected outcomes for callbacks. What percentage of follow-up visits should end up with new diagnosis or interventions to justify the practice? Is it 1 in 100, 10 in 100? Are there predictive variables that would increase the "true positives" without adding to the "false negatives"? Who should decide? It's interesting how professional associations and providers often use the terms "rationing" and "scarce resources" to describe the health care system, while others think it is staggeringly clear that we have a culture of superabundance of some kinds of service (diagnostics, drugs, C-sections) and a chronic shortage of other kinds (comprehensive geriatric care, mental health). When you gather up your first 100 blogs into a best-selling book, a few instalments on this topic will be provocatively useful indeed.

  2. Originally posted by Joy Dobson (Anesthesiologist , Regina Qu’Appelle Health Region) 07/29/08 10:21 AM

    Kishore, you are my new hero. Are you going to the CPSI course for Safety Officers in Toronto in September? It would be great to get a SK core of attendees.