# LOINC Results Codes - Why so many?

**URL:** <https://forum.loinc.org/t/loinc-results-codes-why-so-many/1006>\
**Category:** general-discussion\
**Created:** [January 10, 2019, 9:42pm UTC](https://forum.loinc.org/t/loinc-results-codes-why-so-many/1006 "2019-01-10T21:42:35Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![medmunds](https://forum.loinc.org/letter_avatar_proxy/v4/letter/m/65b543/32.png) [@medmunds](https://forum.loinc.org/u/medmunds)\
**Post date:** [January 10, 2019, 9:42pm UTC](https://forum.loinc.org/t/loinc-results-codes-why-so-many/1006/1 "2019-01-10T21:42:35Z")

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LOINC apparently contains numerous codes for the same lab results. Can someone help me understand why this occurs in the context of the following example?

Filtering for Component “LDL” creates for me the following questions:

1)Why are there multiple codes corresponding to the same test, with the same name?

a. 14 “Cholesterol.in LDL” components

b. 14 “Cholesterol.in LDL 1….7” components

2)What is the difference between these results?

3)Why are the majority of codes apparently not used?

a. Common\_Test\_Rank shows only 3 codes used for results

b. Common\_Order\_Rank shows only one-code used for ordering

c. Common\_SI\_Test\_Rank returns 3-different codes

i. What are SI Tests?

1. Are they research related?

4)Anything else I should know?

Thanks in advance!

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**Author:** ![system](https://forum.loinc.org/uploads/default/original/1X/dbab97ce9b2987d788a376e254fcaae249f3b672.png) [@system](https://forum.loinc.org/u/system)\
**Post date:** [June 23, 2023, 3:36pm UTC](https://forum.loinc.org/t/loinc-results-codes-why-so-many/1006/2 "2023-06-23T15:36:41Z")

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