# Interpretation of LefSe and ANCOM results
**URL:** https://forum.qiime2.org/t/interpretation-of-lefse-and-ancom-results/15107
**Category:** General Discussion
**Created:** [May 26, 2020, 2:47pm UTC](https://forum.qiime2.org/t/interpretation-of-lefse-and-ancom-results/15107 "2020-05-26T14:47:20Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@Eolden](https://forum.qiime2.org/u/Eolden)
#### Post date: [May 26, 2020, 2:47pm UTC](https://forum.qiime2.org/t/interpretation-of-lefse-and-ancom-results/15107/1 "2020-05-26T14:47:20Z")
Dear all,
I am posting this message because I need some help interpretation my results generated with Qiime2.
I attached to this message files that represent lefse and ancom generated to compare three different groups N/Y-/Y+.
Could someone give me some help understanding the generated files?
For example, could you give me a method to determine the W cutoff I have to apply ? In other files, hypothesis is considered as true with a 0 value, when in the attached files W=5 is considered as false.
Thanks in advance for your valuable help.
Best regards.
Maxime
[ancom.tsv](https://forum.qiime2.org/uploads/short-url/qrr5RPILwAjAwhLRpHgBymLkOvS.tsv) (32.8 KB)
[ancom\_6\_LOCAL\_INFECTION.qzv](https://forum.qiime2.org/uploads/short-url/ajwyL54Y42aZEkKVC35r0L9tsh4.qzv) (440.7 KB) [lefse\_6\_LOCAL\_INFECTION.tsv](https://forum.qiime2.org/uploads/short-url/2GrR9NlJvsGxjNWJcTTYjCnXIJU.tsv) (36.6 KB)
---
### Author:  [@Mehrbod\_Estaki](https://forum.qiime2.org/u/Mehrbod_Estaki)
#### Post date: [May 29, 2020, 11:00pm UTC](https://forum.qiime2.org/t/interpretation-of-lefse-and-ancom-results/15107/2 "2020-05-29T23:00:03Z")
Hi @Eolden,
I can't speak with regards to the LEfSe analysis as I am not familiar with their output.
But the 2 ANCOM files you have attached:
ancom.tsv: The top 2 taxa with W scores of 100+ are the only 2 taxa identified to be different between your groups.
ancom\_6\_LOCAL\_INFECTION.qzv: Only the Ruminococcaceae UCG-014 with a W score of 246 is considered different.
With q2-ancom, you shouldn't really have to worry about setting your own W cut off score, this is done under the hood for each run. This isn't like a p value whereby a fixed threshold can be set globally, so the same W thresshold can't be used across different runs. You should stick with the predetermined significance threshold. The low W values (0 or 5 for example) appearing as significant is a known issue with the q2 version of ANCOM. Have a look at this [thread](https://forum.qiime2.org/t/ancom-low-w-taxa-identified-as-significant-issues-workaround-ancom2-code-instructions/6040) for more details on that. You can also check out q2-ALDEx2 and q2-songbird for alternative differential abundance methods if ANCOM is giving you issues.