Screening 21,379 papers with a hybrid RAG pipeline. My M.Sc. thesis was a PRISMA 2020 meta-analysis of feature-extraction methods for EEG-based sleep staging, but the harder part was the screening. I built a hybrid RAG pipeline with an LLM referee layer for content filtering, MIDO-framework structured extraction and a two-stage quality check using the Newcastle-Ottawa Scale and PROBAST+AI, narrowing 21,379 records to a 140-paper methodological pool. Applied DerSimonian-Laird random-effects meta-analysis on logit-transformed F1 scores across W, N1, N2, N3 and REM stages, quantified between-study heterogeneity and mapped feature families to stage-level performance. Published at the 4th International Sarajevo Scientific Research and Innovation Congress, 2026.