| Abbreviation | Expansion |
| PROBAT | Probiotics in the Prevention of Atopy in Infants and Children |
| SP | starting point |
| EP | endpoint |
| CST | community state type |
| IQR | interquartile range |
| AOR | adjusted odds ratio |
| CFU | colony-forming units |
| gDNA | genomic DNA |
| ASV | amplicon sequence variant |
| 16S rDNA | 16S ribosomal DNA |
| CLR | centre-log-ratio |
| ARG | antibiotic-resistance gene |
| MGE | mobile genetic element |
| ORF | open reading frame |
| RPKM | reads per kilobase per million mapped reads |
| PCoA | principal coordinates analysis |
| NMDS | non-metric multidimensional scaling |
| JSD | Jensen–Shannon Divergence |
| GLMM | generalised linear mixed model |
| AIC | Akaike information criterion |
| FDR | false discovery rate |
| DADA2 | Divisive Amplicon Denoising Algorithm 2 |
| NCIMB | National Collection of Industrial, Food and Marine Bacteria |
| CARD | Comprehensive Antibiotic Resistance Database |
| RGI | Resistance Gene Identifier |
| DESeq2 | Differential Expression Sequencing version 2 |
| HUMAnN | The HMP Unified Metabolic Analysis Network |
| MetaCyc | metabolic pathway database |
| CHOCOPhlAn | A pan-genome database used with MetaPhlAn |
| NetCoMi | Network Construction and Comparison for Microbiome Data |