Table 5. Summary of results for all samples (n = 163) from the Adonis and ANOSIM tests for comparing categories using UniFrac data from the closed99 approach.
| Adonis | ANOSIM | |||
|---|---|---|---|---|
| Unweighted | Weighted | Unweighted | Weighted | |
| Study | P < 0.001 | P < 0.001 | P = 0.001 | P = 0.001 |
| R2 = 33.2% | R2 = 33.4% | R = 80.1 | R = 43.5 | |
| Model | P < 0.01 | P < 0.001 | P = 0.001 | P = 0.016 |
| R2 = 11.9% | R2 = 10.4% | R = 53.9 | R = 9.8 | |
| Sequencing | P < 0.001 | P < 0.001 | P = 0.001 | P = 0.529 |
| R2 = 6.7% | R2 = 3.7% | R = 61.6 | R = − 2 | |
| Treatment | P < 0.001 | P < 0.001 | P = 0.001 | P = 0.001 |
| R2 = 24.6% | R2 = 28.2% | R = 33.8 | R = 25 | |
| Obesity | P < 0.001 | P < 0.001 | P = 0.237 | P = 0.001 |
| R2 = 1.8% | R2 = 5.5% | R = 3.1 | R = 20.6 | |
| Site | P < 0.001 | P < 0.01 | P = 0.960 | P = 0.953 |
| R2 = 5.1% | R2 = 2.4% | R = − 5.3 | R = − 6.3 | |
Notes.
According to QIIME documentation, the R2 value (effect size) calculated with Adonis test shows the percentage of variation explained by the factor (e.g., the factor ‘study’ explained 33.2% of the variation in the unweighted distances), and the R statistic calculated with ANOSIM test reflects the degree of dissimilarity (an R value near 1, or 100, means that there is dissimilarity between the groups, while an R value near 0 indicates no significant dissimilarity between the groups). A rarefaction depth of 440 sequences per sample to account for as many samples as possible (only one sample was left out using this rarefaction depth). A total of 999 permutations were used to calculate the statistics.