# External ID. Suffixes \_P and \_TR

**URL:** <https://forum.biobakery.org/t/external-id-suffixes-p-and-tr/9072>\
**Category:** IBDMDB\
**Created:** [September 30, 2026, 5:24pm UTC](https://forum.biobakery.org/t/external-id-suffixes-p-and-tr/9072 "2026-09-30T17:24:39Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Diana\_MAGGESE](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.biobakery.org/diana_maggese/32/3726_2.png) [@Diana\_MAGGESE](https://forum.biobakery.org/u/Diana_MAGGESE)\
**Post date:** [September 30, 2026, 5:24pm UTC](https://forum.biobakery.org/t/external-id-suffixes-p-and-tr/9072/1 "2026-09-30T17:24:39Z")

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Dear colleagues,

I am Diana, and I am working with HMP2 data—specifically, the metagenomics data. My question is: what is the difference between samples with the suffixes \_TR and \_P and those without them? If I wanted to use the data in `taxonomic_profiles_3.tsv.gz` to obtain a single sample per person for each stool collection, which samples would be the most appropriate to consider? I was thinking of selecting those without the \_P suffix to ensure I have only single-end samples, and then calculating the arithmetic mean for each bacterium across the \_TR samples and the standard ones. Could you please clarify?