 |
 |
Rita and Anders, In preparation for a talk on communicating measurement uncertainty to doctors I started asking around our campus for any examples of this. I could not find any clinical results: HR, BP, weight, temperature, cardiac output, ventricular volume, cardiac wall thickness, bone density, imaging lesion size, lung function results etc that were expressed with an uncertainty! Please find attached a couple of slides from this talk about how the MU (or preferably the Result Uncertainty, RU, including within subject and pre-analytical variation?) may be expressed and the effects of the usual way used in non-medical labs (eg +/- x, or x - y). The last three slides (only 7 attached) give my brief summaries of advantages and disadvantages of reporting MU (RU) and a summary. (briefly - lets do it, but cautiously) (I declare that BioRad Sponsored the meeting and the conclusions represent discussions amongst participants at a BioRad sponsored meeting). Regards, Graham >>> Rita Horvath <[log in to unmask]> 19/06/2013 8:02 am >>> Anders, what we in fact do is that we offer adjCa 8using our in-house validated equation) to a restricted group of patients and in a restricted albumin conc range only. We have informed our dr-s about the estimated nature of the calculation (which is only a very rough guide at best) and the need for proper ionized Ca measurement if clinically deemed necessary. This is all commented on lab resports too as a constant reminder. I think in the world of imperfect solutions the best we can do is to inform them clearly and be transparent about the uncertainties associated with our reported results. Just letting them do with results what they think might be right is not appropriate laboratory service, in my view, and in fact can cause harm to some patients. Having said this, I have just recently lectured GPs on inappropriate laboratory testing and when I highlighted to them the concept of measurement uncertainty, biol. var, etc, they became very keen on us reporting results with the uncertainty estimate so that they can take that into account when interpreting lab data. The only anecdote I remember about such an approach is that one Australian lab tried this at least a good decade ago but nearly went out of business as dr-s did not like to see plus/minus figures and felt the lab was not good enough to give them the 'right' result...so they had to stop this practice...I often ask why do we bother then having big spreadsheets of uncertainty calculations if we rarely use this for clinical information - just to plse the accrediting body??? Wonder how many labs report results with uncertainty estimates (!!!NB: estimates)? So this simple question on Ca leads us to a lot of conceptual issues we still failed to solve as a profession, I am afraid. Kind regards, Rita ________________________________ From: Clinical biochemistry discussion list [[log in to unmask]] On Behalf Of Anders Kallner [[log in to unmask]] Sent: Tuesday, 18 June 2013 11:07 PM To: [log in to unmask] Subject: Population based algorithms Dear Rita A pertinent question may be if laboratories shall calculate, correctly, what we know is wrong or leave it to the clinicians to wrongly calculate what is wrong anyway. It is not always that two negatives cancel. Best regards, Anders Anders Kallner, MD, PhD Assoc. Professor (R) Karolinska Univ. Laboratories Stockholm SWEDEN +46 8 51774943 [log in to unmask]<mailto:[log in to unmask]> ------ACB discussion List Information-------- This is an open discussion list for the academic and clinical community working in clinical biochemistry. Please note, archived messages are public and can be viewed via the internet. Views expressed are those of the individual and they are responsible for all message content. ACB Web Site http://www.acb.org.uk Green Laboratories Work http://www.laboratorymedicine.nhs.uk List Archives http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html List Instructions (How to leave etc.) http://www.jiscmail.ac.uk/ --------------------------------------------------------------------------------------------- Illawarra Shoalhaven Local Health District, South East Sydney Local Health District and Sydney Children's Hospital Network (Randwick Campus) Confidentiality Notice This email, and the files transmitted with it, are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, you are not permitted to distribute or use this email or any of its attachments in any way. We also request that you advise the sender of the incorrect addressing. This email message has been virus-scanned. Although no computer viruses were detected, Illawarra Shoalhaven Local Health District, South East Sydney Local Health District and Sydney Children's Hospital Network (Randwick Campus) accept no liability for any consequential damage resulting from email containing any computer viruses. ------ACB discussion List Information-------- This is an open discussion list for the academic and clinical community working in clinical biochemistry. Please note, archived messages are public and can be viewed via the internet. Views expressed are those of the individual and they are responsible for all message content. ACB Web Site http://www.acb.org.uk Green Laboratories Work http://www.laboratorymedicine.nhs.uk List Archives http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html List Instructions (How to leave etc.) http://www.jiscmail.ac.uk/ ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been virus scanned and although no viruses were detected by the system, St Vincents & Mater Health Sydney accepts no liability for any consequential damage resulting from email containing any computer viruses. ********************************************************************** ------ACB discussion List Information-------- This is an open discussion list for the academic and clinical community working in clinical biochemistry. Please note, archived messages are public and can be viewed via the internet. Views expressed are those of the individual and they are responsible for all message content. ACB Web Site http://www.acb.org.uk Green Laboratories Work http://www.laboratorymedicine.nhs.uk List Archives http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html List Instructions (How to leave etc.) http://www.jiscmail.ac.uk/