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. 2024 Feb 6;132(2):026001. doi: 10.1289/EHP13423

Figure 4.

Figure 4 is a flowchart with nine steps. Step 1: Additional P F A S literature searches (November 2019, 2021, December 2022): PubMed: November 2019 there were 1834 records, December 2021 there were 292 records, and December 2022 there are 133 records. WoS: November 2019 there were 931 records, December 2021 there were 168 records, and December 2022 there are 185 records. ToxNet: November 2019 there were 248 records and 2021 and 2022 data not available. Step 2: 1069 records of the duplicate removal, Swift-review used to analyze 2312 records from database searches identification of potentially relevant records bases on application of swift-review evidence stream tags. 208 records of the duplicate removal, swift-review was used to analyze 242 records from the December 2021 update identification of potentially relevant records that went directly to titled and abstract screen in distiller S R. 60 records of duplicate removal, swift-review was used to analyze 202 records from the December 2022 update identification of potentially relevant records that went directly to titled and abstract screen in distiller S R. Step 3: 1069 records of T I A B screen in swift-active screener, excluding 910 records that includes 518 records that are manually screened and excluded and 392 records predicted as not relevant in swift-active screener (and not manually screened). Step 4: 159 records considered relevant or supplemental material based on swift-active. Step 5: 1414 records identified from other sources, 1 record of C E B S, 512 records of P F A S T O X database, 330 records of A T S D R, 6 records E C O TO X, and 565 records of reference list from included studies. Step 6: 1876 records of titled and abstract screen in distiller S R, excluding 1246 that didn’t meet all P E C O. 330 records tagged as supplemental material. 1576 records represent the sum of T I A B excluded or supplemental. Step 7: 264 records of full-text screen in distiller S R, excluding 98 records that are not P E C O relevant. 42 records of tagged as supplemental material. 140 records of the sum of full-text excluded or supplemental. Step 8: 125 records of human and animal studies summarized in the literature inventory. 14 records are of animal and 111 records are of human. 427 records were tagged as supplemental material T I AB plus full text plus inventory that includes 90 records mechanistic (including in vitro or ex vivo or in silico studies, 33 records of non-mammalian model systems, 5 records non-oral or non-inhalation route of administration, 1 record of transgenic mammalian model, 39 records of A D M E and toxicokinetic, 203 records of exposure characteristics (no health outcomes assessment), 15 records of mixture studies, 39 records or other assessments with no original data, and 1 record conference abstracts. Step 9: Under evaluation: 13 records of animal and 111 records of human. Under extraction: 13 records of animal and 111 records of human.

Additional PFAS study flow diagram (3 November 2023). Literature Searches and results are pooled across years. References identified from other sources joined screening at Distiller SR title-abstract review. Some references may have multiple supplemental or exclusion tags. Note: ADME, absorption, distribution, metabolism, excretion; ATSDR, Agency for Toxic Substances and Disease Registry; CEBS, National Toxicology Program Chemical Effects in Biological Systems; ECOTOX, US EPA Ecotoxicology Knowledgebase; HAWC, Health Assessment Workspace Collaborative; PBPK, physiologically-based pharmacokinetic; PECO, populations, exposure, comparator, outcome criteria; PFAS, per- and polyfluoroalkyl substances; PFAS Tox Database, 2019 PFAS evidence map42,45,46; TIAB, title and abstract screening; WoS, Web of Science.