Talk:Reference ranges for blood tests

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[edit] UK Ranges

I'm puzzled by the number of analytes that have "UK ranges" in brackets e.g. 'Sodium: 130 - 145 mmol/L (UK 135-146 mmol/L)'. Surely the UK is not biochemically different to the rest of the world? Indeed it has as much of a racial mix as continental Europe or the USA. I'm assuming that the two different ranges came from two different textbooks, one of which happens to be published in the UK. I think some consensus should be reached for these analytes, and a single range quoted (NB age-, sex- and pregnancy-related ranges really will be different!). Scolaire 15:17, 12 July 2006 (UTC)

I have recently moved to the US from the UK, and strangely enough all recommendations as to reference ranges and even the doses of drugs are different. So I don't think it would be appropriate to just convert values. Actually the reason for this post is that in the US, the reference ranges for serum lipids are in mg/dL. These seem to be in the articles linked from this section, but not here. Jkwan 12:19, 23 October 2006 (UTC)

I have no problem with the difference between SI units and "American" units. What bugs me is a range such as "2.6 - 6.8 mmol/L or 10 - 20 mg/dL (UK 2.5 - 6.4 mmol/L)". Now, you can say "UK 2.5 - 6.4 mmol/L, US 10 - 20 mg/dL" — that makes perfect sense; but to say that a urea of 6.5 mmol/L is normal for anybody in the US and raised for anybody in the UK is bizarre! What's needed for all of these analytes is two sets of agreed reference ranges only - one in SI units and one in "American" units. I may get around to doing it myself some day but I'm kinda hoping somebody else will do it first. Scolaire 20:38, 23 October 2006 (UTC)

Regardless of whether or not the actual normal ranges for these tests in the populations of the UK and US are the same, doctors in the two countries use different values. This may result from the fact that different proffesional bodies in the two countries come up with different recommendations using different sources. I think it is right to quote both - so that patients can see the reference values their doctor uses to make decisions. Incidently, within the UK different NHS hospitals use slightly different reference ranges (for example some hospitals take the upper limit for potassium to be 5.5). Jkwan 19:01, 9 November 2006 (UTC)

Jkwan, you're missing the point - hospital laboratories everywhere use slightly different reference ranges for everything. These may be derived in-house, taken from a textbook or taken from an instrument manual. There is no standard set of ranges for anything anywhere. That is precisely why they are called reference ranges, not absolute ranges or some such. You may as well say "All Saints: 2.6-6.8, St. Elsewhere's: 2.5-6.4" as say "US: 2.6-6.8, UK: 2.5-6.4". There is no national difference between ranges for any of the analytes in this article. The manual for an American analyser (say, Abbott) or a European analyser (say, Roche) will quote the same ranges in America as in Europe, and labs using that analyser will quote those ranges wherever in the world they are. Hospitals using textbooks are just as likely to use Tietz in Europe as in America. What you are saying is that you were accustomed to one set of ranges when you were in the US, and then met a different set of ranges when you went to Britain, but had you walked half a mile down the road you would probably have seen just as big a difference. Patients reading this article will not see the reference values their doctor uses to make decisions, only the particular one (or in this case two) that a particular editor encountered in a particular lab. In the end, it doesn't matter which one we go with — they are all roughly the same and they are only for reference anyway — but there needs to be only one set! Scolaire 21:59, 9 November 2006 (UTC)

[edit] Readability

May I suggest separating the reference ranges and the units used into separate columns. Right now, I'm having trouble with readability. If I already know a test number and unit of measure, all I'm after is the high/low range. That's hard to see with the current setup. Also, I would love to see headers for each column.

I'm willing to do the actual grunt work to fix this, but I didn't want to just go muck in someone else's entry.

dafydd 05:44, 27 December 2006 (UTC)

[edit] Urinalysis

Any opinion on whether it would be a good idea to include the reference ranges for Urinalysis? Standard values are not listed on the urinalysis wiki. If I don't hear from anyone within a week or so I'll add it in. --Robb37 06:01, 18 April 2007 (UTC)

Provisional no. Firstly the article title is "Reference ranges for common blood tests", so urine testing would be excluded. Secondly the "common" tests on urine are those of dip-testing for blood, sugar and protein in a clinic setting (for which a normal value would be "negative"); whereas quantative tests done in a laboratory (eg calcium, oxalate) are relatively infrequently requested.
I'm not sure which tests you have in mind, but they might be better under a new article, perhaps titled Reference ranges for urine tests. David Ruben Talk 13:14, 18 April 2007 (UTC)
Might need make reference/links from Urine and Human urine to this information page :-) David Ruben Talk 13:24, 18 April 2007 (UTC)
True enough. I found this page as a redirect from Normal lab values so I didn't notice the blood qualifier in the article title. While I don't necessarily think that the inclusion of pH, Osmolarity, Specific gravity, etc. would detract from the article, I agree that this would be outside the scope of the article as currently titled. --Robb37 01:29, 19 April 2007 (UTC)

[edit] UK ranges revisited

I have changed all the values in the "Electrolytes and Metabolites" section to the values from Tietz, a reference book widely used in both the US and the UK. Tietz is a US textbook, but in fact was far closer to the so-called "UK" values than the so-called "US" values. All of these "US" values were either unsourced or sourced from 'popular' websites. I hope that that puts this particular discussion to bed. Scolaire 14:37, 14 July 2007 (UTC)

Unfortunately US laboratories, medical journals and textbooks use US units, so Americans who want to look up a value won't understand them. If you want a peer-reviewed source available online with US units, the Merck Manual has both US units and SI units. Nbauman 03:27, 12 September 2007 (UTC)
Different discussion, Nbauman. This was about a previous editor saying that urea was 2.5-6.4 mmol/L in the UK but 2.6-6.8 mmol/L in the US, and the same for other analytes, which it turned out was not so much POV as just values plucked from the air (see UK Ranges, above). US units have been included here where appropriate. Scolaire 08:02, 12 September 2007 (UTC)
Oh, I see now, you have urea in both mmol/L and mg/dL one on top of the other. But if you want a consistent set of both units, you can find it in the Merck Manual. You can also find a consistent set of both units in the New England Journal of Medicine, but I don't know if that's available free to non-subscribers. Nbauman 18:14, 12 September 2007 (UTC)
I don't know what your problem is with Tietz. It has both sets, it is consistent, and it, rather than the Merck Manual, is the standard reference book in Clinical Biochemistry laboratories in the US and Europe. Scolaire 18:21, 12 September 2007 (UTC)

[edit] Recent edits

I'm not happy in general with the recent edits — the tables have been pulled out of shape, the most common tests, i.e. U&E, have been brought down while tumour markers have been brought to the top, and the "Biochemistry" heading has been unjustifiably removed. But let me start with this question: what on earth is meant by "osmolarity: LL <300, UL >300"? Why not just say "LL zero, UL infinity"? Scolaire (talk) 17:37, 2 January 2008 (UTC)

Not having had an answer even to that I have reverted as follows:

  1. "Clinical Biochemistry" is the name of the discipline - it doesn't mean that haematology isn't clinical
  2. de-linked CHEM-7 and CHEM-20: no articles actually exist
  3. "Acid base physiologys" => "Acid base physiology" and moved it to after electrolytes
  4. reverted to original format (most common analytes first)
  5. put phosphate with calcium, where it belongs
  6. put chloride with sodium and potassium, where it belongs
  7. osmolarity => osmolality and enter proper ref. range from Tietz
  8. and maybe more - it's a lot of editing in one go.

Scolaire (talk) 23:07, 25 January 2008 (UTC)

[edit] Further sections and iron-related

I made some edits to this article [1], which, however, need to be discussed before inclusion:

  • Split of clinical biochemistry into smaller sections. As per Section size policies I really consider this hard knowledge, and thus it justifies being split into smaller sections. As it is now it is very hard to do any further contributions. Enabling further section-editing would facilitate this.
  • Addition of iron-related values, since they are clinically important.

Mikael Häggström (talk) 06:38, 17 February 2008 (UTC)