Hi Young,

Thanks for the query

The laboratory values are approved and fixed by FDA (US Food and Drug Administration). The lab values are determined after doing clinical trials on the healthy volunteers. After that, they take the average values of those healthy individuals and fix certain range which is considered to be normal for that particular age and sex and this fixed range is almost accepted everywhere in the world with minimal discrepancies.

In certain labs it so happens that the values will differ slightly depending upon the instrument and the solution used for the test. Hence each lab gives there own set of these normal range values which needs to be compared. This does not happen with all the investigations.

Hope I have answered your query, if you have any more doubts you are welcome.

Regards
Dr. Naveen Kumar

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