Dr Tim Senior, a GP working in Aboriginal health, provides the following advice for anyone reporting on medical tests (or indeed anyone wanting to understand the media’s reporting of screening and test issues)…
“I need a prostate check and a colonoscopy”
“Oh. What makes you say that?”
“Well, I was listening in 2GB the other day….”
That was a recent conversation I had with one of my patients. I am grateful that I was trusted more than 2GB in the end, and he ended having a faecal occult blood and no prostate test.
Last week, the Sydney Morning Herald went for the Executive prevention market with an article headlined “Over 40? Five Tests you need right now.” The urgency was illustrated, somewhat improbably, with a photograph of a fully gowned surgeon silhouetted by operating lights peering down at you, defibrillator in hand with the caption “The view you don’t want to see.”
It’s interesting to note that there was no overlap in tests recommended. As far as I know there is no evidence to suggest different screening tests based on whether you read the Executive Section of the SMH or listen to 2GB. These items on medical tests are really marketing fear. “Get these tests and reassure yourself.”
What’s the problem if people want to reassure themselves? Well, there wouldn’t be a problem if it worked. But it doesn’t work. A recent systematic review looking at testing for low probability conditions shows that having a test doesn’t reassure people.
It’s also worth asking if the tests will end up making you healthier. It might seem like a no-brainer that finding a disease earlier of course makes you better! But some tests don’t find the disease earlier, sometimes the disease wouldn’t have made you ill at all, sometimes you find it earlier but there’s no good treatment for it, and sometimes having the test itself makes you unwell.
Fortunately, all of these questions are the sort of questions that can be answered by randomised controlled trials, where you compare doing the test with not doing the test and you see whether it actually does make people live longer, happier healthier lives.
GPs are for the most part the ones discussing and requesting these tests – it’s a huge part of what we do, and we see the times they save lives, and we see complications, and the stress and anxiety that goes along with that. Sometimes the best bit of advice in medicine is “Don’t just do something. Stand there!” Fortunately for us, the RACGP regularly reviews the evidence about what tests are likely to work and what aren’t, and publishes this in the so called “Red Book.” There’s also a version for prevention in Aboriginal and Torres Strait Islander people written with NACCHO (Declaration – I was one of the writers of this). So if you want to see what tests are recommended at your age, you can go to this chart (PDF), find your age across the top, and read off the interventions down the left side. You’ll find that coronary calcium score, coronary angiogram and colonoscopy aren’t recommended. You’ll see prostate checking is not recommended. You’ll see that screening for depression is only recommended if comprehensive support services are available, otherwise it does more harm than good* (and the K-10 is not the recommended tool). You’ll see that advice on appropriate alcohol intake is there, though it’s a bit more complicated than just “how big is your glass?” And both blood pressure and cholesterol measurement are recommended, but as part of an assessment of absolute cardiovascular risk, which puts several measures together to work out how likely you are to have a heart attack or stroke over the next 5 years. You can check yours here.
It’s important to note that this information only applies if you don’t have symptoms. If you do, then these tests are not screening, but diagnostic, and you are much more likely to benefit. By its nature, screening brings in people for medical tests, which cost money, and also cost an opportunity to perform that test on someone who needs it – inappropriate preventive tests can not only harm the individual, but harm other individuals who are unable to get the test and harm the health system in costing money that could be spent on doing something that actually works. That’s why the evidence (including evidence of cost benefit) is so important, especially as budgets get squeezed. (There’s an interesting article here looking at procedures that probably cost the health system money without generating any health benefits).
So, if you work in the media and want to do a report on what medical tests you need to do, here are the 5 Tests You Must Do Today! (You can imagine a scary picture of me shaking my head here if you wish!)
- Imagine this was a senior politician telling you this information. How uncritically would you accept it? Are there any conflicts of interest? Use your same sense of scepticism.
- Is there a consensus of opinion? Do GPs and specialists agree? What do major guidelines say?
- Will doing this test make me live a longer healthier life? Show me the evidence. And ask someone else to have a look at the evidence.
- What are the harms from this test, and any subsequent tests or treatment needed?
- If you’re going to interview someone whose life was saved by having this test, interview someone else who has suffered side effects or complications. (But beware false balance – see point 2 above!)
*NB – Screening for depression is asking the same set of questions to everyone, whether or not they have symptoms. The evidence shows that doing this only works with a comprehensive mental health support team, and this should certainly inform policy about mental health. However, I do want to be clear that this does not mean we should not be asking about mental health symptoms, or that there is no evidence about treatment of mental health problems. It means that we should use clinical judgement, in asking and assessing, rather than a single tool applied to everyone.
Croakey suggests that for further reading on this issue, Gary Schwitzer’s (US-based) blog is a great place to start http://www.healthnewsreview.org/blog/