T4 range 6.5 - 17 pmol/L

[sue_b]

Has anyone seen a range similar to this? It is from the Isle of Man. When I lived there and had my thyroid tested ( between 2005-2009) their range used to be 9-24 pmol/L

Any ideas why there would be such a big change?

thank you

[greygoose]

Presumably because they changed their machine. The range depends on the machines they use to analyse the blood.

[sue_b in reply to greygoose]

Hi greygoose, I see. The range is unusual though isn't it?

[greygoose in reply to sue_b]

It is lower at both ends than we usually see. But we see many, and varied ranges on here.

[diogenes Remembering]

Frankly the FT4 assay they used is worse than third-rate. The range is way too low and out of line with virtually any other range I've seen. An acceptable test will have a lower limit around 10 and an upper around 23/24. That's a ratio of 2.4/2.3 to 1 top/bottom. The assay they've used has a ratio above 2.6, That means it either classes too many hypos as normal or too many as hypers when some could be normal. If the former, then with the silly way TSH is used as a hypo test, they'll dismiss far too many ill people as being normal when thy are not.

[sue_b in reply to diogenes]

Thank you diogenes, exactly my thoughts, the range is ridiculously low. As they have also increased the upper limit of the TSH range since 2009, when I was last tested there, god help the poor buggers who are reliant on that system.