I recently had a lightbulb moment on realising that the Medichecks Ferritin range has changed! I had an NHS test a couple of weeks ago and my ferritin was 56 ug/l (15 - 200 ug/l) and realised this was rather low for Hashimotos. I decided to do a Medichecks iron panel test and have, much to my humiliation, discovered that the ranges have changed and I have been looking at the result believing it to be ok - it was 86.1 ug/l (30 -650 ug/l) I’m now completely baffled as the Dr’s report said I was fine but the tracker beneath the result was at rock bottom - lower than it’s ever been. I worked the percentage out to be 9% of the range, which sounds dreadful. Please, please can someone tell me how to read it accurately? It’s all very confusing!!
I’m hoping this might be an answer to a lot of recent problems but am kicking myself for not having realised sooner. Or maybe not . . .
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Rainbow47
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Did you do a Home Iron Test (the full iron panel which includes serum iron, saturation percentage, TIBC, ferritin and CRP with Medichecks or was this a ferritin result within an Advanced Thyroid Test? It's not that Medichecks have changed their range, it depends which lab the sample was sent to for testing.
I do iron panels with Medichecks and they always go to County Pathology and the ferritin range is 13-150 for females of all ages.
The Advanced Thyroid Test is often sent to Inuvi lab which has this wider range of 30-650 for ferritin anyone over 60.
I have trouble taking the Inuvi range seriously but I don't think you can compare ferritin tests from different labs anyway, even Medichecks says to stick to the same lab.
Some experts say the optimal ferritin level for thyroid function is 90-110ug/L but unfortunately they don't give a range or say whether it's for both males and females.
From what I've seen on the forum and from personal experience the Home Iron Test (iron panel) always seems to go to County Pathology and most of the time the Advanced Thyroid Test seems to go to Inuvi. It can always be requested that they use your preferred lab for whichever test you're having and ask them to confirm this before sending off your test.
Never send for two tests at the same time, one test per order is recommended here otherwise there's a chance they'll bundle them together and treat as one test with one return envelope rather than do them as separate tests with two return envelopes.
Just to confirm, a year or two ago, when I too had a query about why Medichecks ferritin test had gone up to the huge 30-650 range and they said if I contacted them before I did the test they would make sure the sample went to the lab with the smaller range.
In the past when Medichecks used to only use the one lab (County Pathology) for all their tests, they would do what I described, ie bundle multiple tests into one, send more than one vial and send just one return envelope.
Now they are using Inuvi for some of their tests it seems that whenever the Advanced Thyroid Test is posted here it always seems to have been sent to Inuvi, maybe that is their default now I don't know because I don't do that test with Medichecks.
So if they are going to use two different labs for the two tests then of course they will send an envelope for each lab as they did with you.
Because we don't know which lab will be used (and we now know that some Home Iron Tests are sent to Inuvi whereas all mine have been sent to County Pathology), then for those members who struggle to fill more than one vial it's probably best if they order tests individually and do them on different days rather than risk the multiple tests being bundled together and having multiple vials to do at the same time.
Thanks SeasideSusie - I don’t see the point in doing these tests if they cannot be correlated in some way when they are put together! You’re right it is Inuvi. When looking at my ferritin result would you read that as high or low? I just want to know whether it’s adequate for my thyroid, which I believe should be at approx 100 ug/l. I’ve written to them several times now and they’ve come back with the same blurb both times with a load of b . . . . . . . . that anyone other than a doctor wouldn’t understand!!🤣 I really want to know how to read the results because looking at the 86.1 ug/l it looks reasonable in the grand scheme of things but it’s so low on the scale that I immediately see it as being too low for me, particularly as their tracker has put it at rock bottom. To add to that I’ve been incredibly fatigued for the past couple of months but have now started to supplement with iron and am already much brighter and less tired. What I would really like to know is is it good or is it bad for me??
My son’s a doctor, knows nothing about the thyroid but reckons I should just go by my NHS results and only get T3 and T4 tested privately as NHS won’t do them. He’s got a point!
So was this the Advanced Thyroid Test and you only had ferritin tested?
When looking at my ferritin result would you read that as high or low?
Personally I can't take this range seriously so I can't answer that question.
What was the CRP result, CRP is an inflammation marker and if it is raised (showing inflammation) then ferritin will be falsely raised because ferritin rises with inflammation. So if CRP was elevated then your ferritin result is not a true result anyway.
Ask your son what range they use for ferritin for a female over 60 at his surgery or hospital. At my surgery it's 15-300 for everyone and even then I don't compare it to the range County Pathology use. I only ever take notice of the iron panel and use that as my guide.
have now started to supplement with iron and am already much brighter and less tired. What I would really like to know is is it good or is it bad for me??
We always advise here not supplement with iron unless a full iron panel is done, ie serum iron, saturation percentage, TIBC, ferritin plus CRP. This is because if you have a decent serum iron level and good saturation then supplementing with iron will likely take these too high which you don't want, too much iron is as bad as too little. You can have low ferritin with good iron/saturation and in that case you'd try to raise ferritin through diet not with iron tablets.
If you haven't done the Home Iron Test then that's what I would do and ignore the ferritin result that has come from Inuvi which I'm guessing is from an Advanced Thyroid Test.
If you are going to continue with the iron tablets then it's important to do the full iron panel regularly to monitor your level (every couple of months).
I’ve written to them several times now and they’ve come back with the same blurb both times with a load of b . . . . . . . .
Good morning SeasideSusie - thanks for your interesting response. Here is the reply I received from my first two enquiries about the result. I’ve asked again if they can explain why the tracker puts me at rock bottom on the scale!
Differences in results and their respective reference ranges are commonly witnessed in results being processed by different labs. Reference ranges can vary between labs if different methods of analysis are used. Labs also determine their reference ranges based on studies from their local normal populations and clinical research. There is currently a bit of debate in clinical research studies about what the limits of the reference ranges should be, but at Medichecks, we interpret levels based on clinical guidance from the British Medical Journal and NICE guidelines. The NICE guidance advises that levels below 30 should be considered as iron deficiency, with no clear recommendation of an upper limit, and the BMJ guidance we follow advises 300 as an upper limit for post-menopausal women and men, and 200 for pre-menopausal women.
I can see that the samples were taken 11 days apart, which is a significant enough timeframe to cause biological variation. Ferritin levels can also increase over a few days with increased dietary intake, any inflammation in the body (due to infection or flares of chronic inflammatory conditions), liver & kidney conditions, increased alcohol intake, and also when your thyroid is in an overactive state.
just jumping in in this as I did a home test via Medichecks and that was Inuvi with frankly ridiculous results. I asked for retest but got nowhere. I’ve used Medichecks for years but now will find tests elsewhere
I’m coming to that conclusion too - am very disappointed, particularly in their response. They were a great asset in the support network for the thyroid world!
Transferrin Saturation 49.7% (25 - 45) HIGH result
Ferritin 86.1 ug/L (30 - 650)
Bear in mind that I had started to take a small amount of iron supplement as this was a re-run test of one that failed the previous week, although they did manage to get a ferritin result of 97.8 ug/L! That could be why the Iron is reasonably high?? It’s all a great big mystery to me!
Those results show that you don't need to supplement iron because serum iron and saturation are high and taking iron will take them too high and maybe lead to iron overload/toxicity. However, it's possible that supplementing iron before this test has caused the high results, when testing iron any supplement should be left off for at least 24 hours, some say a few days. To know if you need to supplement iron then leave off any iron tablets and iron rich foods for a week to get a baseline.
Hi SeasideSusie - I received another reply from Medichecks this morning regarding my Ferritin result which has a little more of an explanation than before, though I’m still not completely satisfied. I attach it below for your info. I will reply again but wonder if you have any further observations I should put in my reply?
Thank you for your queries. Customer care have passed on the following for my attention:
MY QUERIES
“Thanks again for getting back to me, however I feel that several of my queries were not addressed! Firstly - the result of 97.8 ug/1 looks very reasonable by the old range standard but for a range between 30 - 650 ug/1 it appears to me to be very low. Could you please confirm this? Secondly, you did not comment on why, on your graph, my level appears as the lowest it has ever been! This is what has led to my suspicions about how easy it might be for a lay-person (or even your doctors!) to misinterpret the reading as a result of the change to a different laboratory and its wider range for the test."
THEIR REPLY
I am sorry your questions were not answered the first time around. I understand your concerns about the differences in the reference ranges. As far as I am aware, the Inuvi lab reference range of 30-650 is wider as it has been influenced by their population data, where there was a greater spread of results.
As already mentioned, differences in results and their respective reference ranges are common in results processed by different labs. Generally speaking, reference ranges can vary slightly between labs if other analysis methods are used. Labs also determine their reference ranges based on studies from their local normal populations and clinical research; sometimes, this can cause more significant differences in reference ranges.
The NICE guidance advises that levels below 30ug/L should be considered as iron deficiency (regardless of the lab processing the results), and reassuringly, your level of 97.8 ug/L is significantly above this.
Our result tracker graphs account for how reference ranges can vary between laboratories. For the vast majority of blood results, this helps to track them over time. This is why interestingly, your last result appears to be the lowest it's ever been despite its absolute value does not suggest.
I'll also illustrate this using a fictional example. Laboratory A tests a patient's blood sample and returns a result of 2, with a reference range of 1-3. Laboratory B tests the same blood sample, they produce a result of 4, but their reference range is 2 to 6. In this case, the result is precisely in the middle of the reference range for both laboratories, so our tracker graphs would show a straight line, even though laboratory A's result is lower than laboratory B's.
I hope I've answered your questions. If not, please do not hesitate to get back in touch.
Our result tracker graphs account for how reference ranges can vary between laboratories. For the vast majority of blood results, this helps to track them over time. This is why interestingly, your last result appears to be the lowest it's ever been despite its absolute value does not suggest.
This is how I felt reading that 🤔😵🥴🤪
Now I've only had results from one lab (County Pathology) with Medichecks so my graph makes a lot of sense, and the results are comparable. You can see what mine looks like in the attached screenshot.
I've only had ferritin tested with my GP on one or two occasions, last time it was April 2022 just 4 days before I did a Medichecks Home Iron Test. The GP range was 15-300 and my result came in at 49 (11.93% through range). The Medichecks (CP) result came in at 73.8 with a range of 13-150 (same unit of measurement) which gives 44.48%, (ignore the ferritin result of 88.3, it's showing the June 2022 result and doesn't show my April results but you can see it on the tracker). There is a big difference in the ferritin level. This is when I decided to stick to the one lab (ferritin isn't normally done with GP anyway).
I wonder, from what they've written, when two labs are used, are they still plotting the result from the new lab on the same graph as the results from the other lab? Because to me that doesn't make sense at all, I just don't see how you can compare them as their last sentence above alludes to. My brain doesn't fire on all cylinders at all times so maybe I'm completely missing the point 🤷♀️
I'll also illustrate this using a fictional example. Laboratory A tests a patient's blood sample and returns a result of 2, with a reference range of 1-3. Laboratory B tests the same blood sample, they produce a result of 4, but their reference range is 2 to 6. In this case, the result is precisely in the middle of the reference range for both laboratories, so our tracker graphs would show a straight line, even though laboratory A's result is lower than laboratory B's.
In that example it's pretty obvious that the results are 50% through range for both tests and we all can see that. This example doesn't explain why your percentage through range is so different with Inuvi compared to your GP result.
Am I making sense, I'm beginning to doubt myself now 🥴
I understand what she is trying to tell me but it still doesn’t make any sense, and the graph/tracker is a complete nonsense. I’ve attached mine for your info. I’m planning to write back and tell them I think this is very misleading and needs addressing before someone does themselves some harm as it is setting a precedent for total confusion and risks many of their clients misreading the situation. I, for one, look at the graph for confirmation that things are getting better/worse and I guess some would use this criteria for determining the situation rather than the actual result! Someone, like me, could start dosing themselves with loads of iron when actually they don’t need it. Surely in this day and age it wouldn’t be difficult to convert Inuvi’s results to the usual range? With a computer maybe??🤣 Or do you think I’ve missed a point somewhere along the way?🤔
Then I am at a complete loss to understand why they have put the Inuvi results on the tracker when all the other results are CP, to me it doesn't make sense, I don't think it's possible to compare them and their explanation is nonsense to me!
This is why interestingly, your last result appears to be the lowest it's ever been despite its absolute value does not suggest.
So what do you take notice of? The seemingly good level of 86.1, or the poor percentage through range and the position on the tracker compared with the CP results? Has your ferritin level really plummeted so much, I actually doubt it.
I really don't think Medichecks is doing itself any favours, there have been quite a few posts on the forum about this, it's confusing members and they don't know where they stand with the ferritin test in particular.
This is an old post (3 years ago) which shows how Thriva presented their results on a bar graph. That test was done with County Pathology I believe. Even back then, if you read through that thread, the OP had also had NHS results with a different range and there was the same confusion back then!
Thank you - interesting but nothing showing the Inuvi recent ferritin ranges. I’m becoming a bit obsessed about it now, but I have progressed a little in that I think the actual figure is reasonably accurate in the grand scheme of things once you get over the huge range. It’s the tracker that bothers me most of all as it could so easily be misread if you weren’t paying attention or were confused about the figures as I was, and some vulnerable individual could put themselves on an iron supplement when it wasn’t necessary. Surely a scenario that Medichecks should bear in mind?
I’m in the throes of writing to them again suggesting they might want to rethink their presentation of results reminding them that we, as their clients, should be listened to bearing in mind the numbers now deserting them as a result of these changes. Did you know that CountryHealth (Oliver Frey) has told his clients not to use Medichecks in view of the Inuvi results?
It’s been over a week now but I’ve finally had a reply from Medichecks. It looks as though they are now looking into the problems with Inuvi, albeit the ferritin results, and it would seem they are reviewing other problems that have arisen with Inuvi. I feel reasonably satisfied by the reply. Hopefully they now appreciate that their customers are not medics and will simplify the results as best they canto suit the layperson. Here it is -
I am sorry that I haven’t been able to explain the issues you’ve raised to your satisfaction. Thank you for bringing your concerns to our attention and expressing them clearly from a customer’s point of view.
There is some debate and controversy among different test providers about ferritin reference ranges. Medichecks has acknowledged this and we are currently performing a review of the Inuvi ferritin ranges. As we recognise that the upper limit of 650 ug/L is higher compared to many other test providers, we requested the lab to provide further supporting evidence, and they responded with this guidance from the Association for Clinical Biochemistry and Laboratory Medicine: acb.org.uk/asset/AFFD023A-5...
We are also currently conducting a thorough analysis of the reference range limits using our Medichecks data. We hope to present our findings to the laboratory soon as this could determine a revision of the reference ranges.
As an interim measure, our reporting doctors are following the clinical guidance from NICE for the lower limit of iron deficiency diagnosis and the British Medical Journal guidelines for interpreting raised ferritin levels. We understand your concerns and apologise for any uncertainty caused. We will keep you updated on the review's outcome and appreciate your efforts in bringing this issue to our attention.
Thank you for flagging this: "My point is that I find it wholly inappropriate to expect your very valuable customers to have to try and understand (in fact read) these results with new ranges for themselves with no explanation that things have changed." I apologise that you were not aware of the changes in reference ranges in respect of switching some of our tests to Inuvi. We greatly appreciate your valuable feedback. Our team is currently conducting a review of our communication processes, and we will certainly take your insights into careful consideration.
If you post on this thread and reply to me directly as you just did then I will get notification, the post will go to the top of the feed for a short while, also members will see it if they click on "Recently Active" posts.
Alteratively you could start a new post giving a bit of background and linking back to this one. That way it would go to the top of "Latest Posts" where all brand new threads go until it drops down the page as new posts are made.
my dr didn’t tell me in December my ferritin was 9, I went 2 weeks ago feeling exhausted and my ferritin is now 7. My th level had gone up from 1 to 3.6 (on 50mg thyroxine) I asked if I had hashimotos and she said yes as antibodies raised.
Ferritin 86 sounds amazing mine has never ever been that, 29 was highest. What is the link please?
Dr not overly concerned as hb level was 10 so not very low?
Hi Mumzy09 - that’s just what I thought but if you look at the ranges you will understand my concern as I’m usually pretty low and struggle to keep my level up!
Just to point out that ferritin ranges can be among the most difficult to understand.
And this is not because we are unable to understand - it is that everything to do with them is severely compromised.
They change by sex, age, whether menstruating, pregnancy, etc. - as well as which lab did the test.
A high number is regarded as fine in some people, but worrying in others. Take something like 400. For an older male, that is not an issue. But for a younger woman, it is itself sometimes regarded as an issue.
Why a younger woman has a relatively high ferritin level is something that needs to be considered. But making the actual number itself a concern is inappropriate.
And at the lower end of the scale, and below the end of the scale, say 10 or 20, the result is often claimed to be explained by menstruation. But it just should NOT be that low.
yes my dr was quite off about 7, she said that as my hb level was not drastically low she wasn’t worried. I’ve had a colonoscopy and pelvic mri recently and there’s no concern about internal blood loss, my periods are much lighter than before (47) so she seemed to think I was just someone with low levels.
Morning Helvella - just so you have the full picture I’m an old woman of 76, though not quite senile yet (in my opinion)! I had read somewhere that some labs change to the 30 -650 range for people over 60! All I really want to know is how this result compares either with other labs or NHS results! It seems impossible to make a comparison, so why take the test? I consider it almost irresponsible to even offer these tests when ostensibly the majority reading the results are not medically trained and common sense can’t explain them!
I have just called my surgery and been referred for an iron transfusion…. I had one before in pregnancy.
I will get a copy of my full blood tests and make my own post, sorry for high jacking. Good luck with yours. I’ve been on spat one sachets but they seem to work on the blood but not the stores.
Wow - that was quick! No problem at all - it’s all interesting stuff. Hope all goes well and I will keep looking for that all important answer! Interesting about Spatone - I’ve been taking two sachets but have now ordered heme iron from USA - been highly recommended by others. Good luck!
I was prescribed 4 sachets of spatone per day by the dr. For about 2 years now after iron tablets caused havoc with my ibs. To be fair I struggle to remember to take 4 along with thyroxine etc so I hadn’t taken it seriously and as they didn’t let me know it was 9 in December I had no idea it had dropped so much. I only went to dr again as struggling to get up and focus!
This is a summary of what I have read up and found out about iron supplements over the past few years. I am not in any way medically trained. You are strongly encouraged to check every detail before making any decisions for yourself.
This happened to me last week, I've been working to improve my ferritin levels and they have been going up nicely. My levels last week had increased again but the chart showed a massive plunge to a low of 6.7% through the range!
I wrote to Medichecks and seem to have had a similar response received by others. I've now written again challenging their response and requesting hard evidence/data to support the extraordinary reference range which seems to kick in at age 60. It's good to know others are concerned too.
As promised to Seaside Susie, and 6 months later, please see response I've had today from Medichecks. I'm just sad it didn't come in time for Seaside Susie to see that they had eventually listened to us!
'Hi Carol,
Happy New Year.
Thank you for your incredible patience while you have been awaiting the outcome of our ferritin reference range review. We conducted this with Inuvi lab, which has now changed the reference ranges to the following:
Females 18 ≤ age < 40 30 to 180
Females 40 ≤ age < 50 30 to 207
Females 50 ≤ age < 60 30 to 264
Females Age ≥ 60 30 to 332
Males 18 ≤ age < 40 30 to 442
Males Age ≥ 40 30 to 518
The lower limits of 30 are by the NICE threshold of <30 for iron deficiency. Our review of Medichecks data has determined the upper limits. This retrospective study used a large dataset of blood test results from 25,425 healthy participants aged 18 to 97 over seven years. This is the most extensive study on ferritin reference ranges, and we hope to achieve journal publication so that these ranges can be applied more widely.
I wanted to express my gratitude for your feedback in July 2023, which undoubtedly served as a motivating factor for this study.
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My first Medichecks results 
High Ferritin 
Medichecks results.
New medichecks blood results 
