Forum

Thinking of making a complaint

Wonder if I can get some comment from any statisticians amongst you.

I had somatosensory evoked potential (SSEP) tests on my limbs. The lab report mentions that the P 37 potential was measured at 44 ms for my right leg and 47 ms for the left, compared to the lab mean of 37. The ‘upper normal limit’ (3 standard deviations) given for this test is 44 ms. So I take from this that typically , something like 99 people out of every 100 would have a better result than for my right leg, and considerably more would better my left leg, which I would assume must be categorised as having an ‘abnormal’ result. The difference between each leg of ‘3 ms’ I suspect is also tending towards abnormal but I cant find a reference to check this.

What I fail to understand is the result being characterised by the neurologist as a ‘slight delay’ and ‘essentially normal’.

For my VEP test, the P100 for both my eyes were within ‘normal’ limits, but the inter-optic difference of ‘9’ (97 for the right eye, 107 for the left eye) is at the very upper limit of normal (I.e. 3 standard deviations away from the ‘mean’).

So with both the SSEP and the VEP, I would have thought there were grounds for entertaining at least the suspicion that something isn’t quite right.

In addition, I have had an MRI which found a lesion immediately behind one eye in the area of the optic nerve, and I have had a positive urodynamics test for detrusor instability, though my LP was reported as normal.

When my GP wrote to this neurologist recently because of further issues I am having with vision - seeing multiple images; he declined to see me, essentially on the basis that there wont be anything ‘organic’ wrong.

I just don’t see how he can logically conclude this from the data. I am thinking of making a complaint. Anyone think I have a point?

i think these neuros should give better explanations!

may as well be written in chinese!

good luck

carole x

Like Carole, I found it to be as clear as chinese!

But thinking properly now…if you have an eye problem…what about asking to see an eye specialist?

pollx

Hi

Are you saying the neurologist thinks because of these test results, you don’t have MS?

Obviously he could be quite right, the absence of any evidence from LP plus only one lesion might indicate that, but as for the SSEP and VEP results, I read Carole’s comment as it being as clear as cheese rather than Chinese. But either works really.

It does seem maybe as though you have an eye problem??

What does your GP make of the test results? Does he/she agree that seeing a neurologist is inappropriate? Maybe the GP could try referring you to another neuro or an ophthalmologist (who could then refer you to a neurologist if they think it’s appropriate!)

I have to say that when I was first tested for MS (in 1997), I had MRI, LP and VEP. There was only one lesion on the MRI, nothing radical on the VEP and results from the LP that indicated something demylinating. I was told “you don’t have MS”, which I believed. It was only five years later, after quite a few relapses that I decided to chase up what was wrong with me and found more than one lesion, and of course had had multiple relapses. Meaning I did have MS!!

So, in your place, I’d probably be looking for a second opinion of some sort.

And preferably one that’s been translated from cheese to English.

Sue

1 Like

I agree that a second opinion is probably the way to go.

Alison

Yes, you have a point!

Three standard deviations (SDs) should cover 99.74% of the sample, and since this will be above or below the average value, it suggests that just over one third of 1% of the sample would get a similar result.

The problem is that you, and the rest of us, do not know how big the sample is. In short, you have a meaningless statistic.
It may be correct, but we have no way of knowing.

When I was running a set of experiments in a psychology department, anything that gave a result that was more than two SD (after analysis) would be flagged up as significant, and any individual scores more than three SD would be dropped from the analysis on the grounds that they would skew the results. I would expect that every psychology department would work the same way. Maybe your neuro can justify his comments with some raw data, but without that … … .

While sample size does matter, I would argue that greater than 3 SD is “abnormal” and should be treated as such. And once you have said that, “close to” 3 SD on another test must also be “close to” abnormal.

I would hesitate to make a formal complaint, because you do not have all the numbers (and he may have been looking at a sample size in four figures), but you do have grounds for asking to be referred to another neuro. Who knows, such a request might just get your GP to challenge the conclusions - and given his refusal to see you again he would probably be on your side.

Double vision / multiple images? Seek a referral to an Opthalmologist who can at least get an MRI done to look at the optic nerve.

Geoff

Thanks for all your input guys. Sue I think he doesn’t think there is any significant ‘real’ disease, know what I mean? I remember having a strong disagreement when I first saw him. He told me he was only doing the tests to reassure me and they weren’t going to show anything significant. He made some comment like ‘I haven’t been doing this job for 20 years to not know what I am talking about” He reminded me of CJ and his posturing catch phrases from The Fall and Rise of Reginald Perrin, like “I didnt get where I am today by putting green frogs down my underpants”, or “I didnt get where I am today by biting peoples bottoms in the changing room” I remember he actually sent me for the SSEP test twice and now I think it was because he couldn’t believe the first result and wanted to show it was wrong. In fact I have spent the last 3 years believing his pronouncement that it was only slightly worse than to be expected and that it was so small a difference as to not to be able to exclude measurement error. I am so angry that he refused a re-referral and in effect warned my GP not to take me seriously, that I requested copies of the relevant notes from my file and am coming to believe he has probably fundamentally misrepresented the facts on my tests. Geoff I guess the upper normal point could be based on a small sample , but I would hope it had a much firmer statistical basis given that it is being sent out from a busy hospital lab to consultants to be used as a reference point by which to assess the test results. I am going to show the notes to my GP and take it from there. Poll, Sue, It was an optician and then an eye specialist at the hospital eye clinic that contacted my GP with the suggestion that I need a re-referral. Geoff , I mean something quite different to double vision, literally multiple vision. At least once a day now, often several times, I briefly see bright objects clearly repeated may be 20 times strung out like a string of beads with my right eye. Here we go!

Hi Sue, i found out buying my notes for 50.00 that I had overall in a couple of years 3 lesions on different parts of top of spine and neck, positive VEP tests bilaterally, (both eyes one side was 118, the other 111), and something demylinating on my LP, but still not diagnosed with MS, only wait and see possibly until I went in for something slightly different, and had another MRI and scan and they found new lesion on my spine in a different place, and i was told i had MS, and also diagnosed with TEA. It seems some neuros dont want to give the label, i am convinced the reason for my delay is my age and birth date. I mean in 2000 i went blind and it turned out over time i had ON, if i had been born in 1970 I think i would have been diagnosed then and there instead of which being born in 1951, it was possibly MS even with large amount of small lesions on my brain, which could have been demylinatating but the radiologist said it was more likely my age lol…

Your experience sounds like mine, but in my case it definitely wasn’t my age, it was 1997 and I was only 30. But there used to be a general belief that unless it’s absolutely definitely MS, it was better not to tell the patient that it might be. There was some sensible reasoning at that time, in that there was virtually no access to any DMDs. The ‘risk sharing scheme’ whereby beta interferon became available on the basis that the NHS could have it for less money while they were proving that they worked. This meant that in 2002 when I was diagnosed, I could get beta interferon. Nowadays of course, there are so many DMDs, there is absolutely no argument that it could benefit the patient not to be told that it is likely to be MS.

Sue

Managed today to obtain the results of the repeat test of the SSEP done a few weeks later by phoning the relevant dept (as there was no reference to it in the copied file notes I received). The results are very consistent with the first test but slightly worse: right leg 44 ms, and left 48, compared with earlier test of 44 and 47. I remember the neuro downplaying my SSEP test result partly on the grounds that as it was a small deviation from the norm he couldn’t dismiss it arising just from measurement error. Now I see that this was also bullshit in that not only is it not a small deviation, but the high consistency in the results suggests to me accurate measurement, unless the error was non random and of gross proportions.