3.1. Defining the Set of Eligible Transcriptomics Studies in the Context of Peritoneal Dialysis for the Current Meta-Analysis

The current meta-analysis focused on untargeted human transcriptomics studies in the context of PD that used an approach. We therefore included all studies reporting results of whole-genome microarray or RNA sequencing experiments. We furthermore excluded studies solely focusing on non-protein coding RNAs (e.g., miRNAs) as well as studies with a focus on infections or malignancies (mesotheliomas).

We searched the PubMed database for PD transcriptomics datasets in December 2020 using the following search query: “(peritoneal dialysis OR mesothelial cell OR mesothelial cells) AND (gene expression profiling OR microarray)”. Titles and abstracts of resulting publications were screened for studies meeting inclusion and exclusion criteria as defined above. We subsequently searched the two gene expression repositories ArrayExpress and the Gene Expression Omnibus (GEO) using the following search queries: (“peritoneal dialysis” OR “mesothelial cell” OR “mesothelial cells”) AND (gene expression profiling OR microarray) NOT (mesothelioma OR cancer OR ovarian OR proteomic OR carcinoma OR melanoma). We further restricted the resulting list to studies in human.

We recorded the following information from studies considered for the current meta-analysis: (i) sample type, (ii) sample number, (iii) PubMed ID, (iv) GEO GSE code (if available), (v) experimental platform, (vi) conducted comparisons, and (vii) criteria de-fined by the authors to define differentially expressed genes.