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Background Laboratory parameters and the associated clinical outcomes have been an area of focus in COVID-19 research globally. Purpose We performed a scoping review to synthesize laboratory values described in the literature and their associations with mortality and disease severity. Methods We identified all primary studies involving laboratory values with clinical outcomes as a primary endpoint by performing data searches in various systematic review databases until 10th August, 2020. Two reviewers independently reviewed all abstracts (13,568 articles) and full text (1126 articles) data. A total of 529 studies involving 165,020 patients from 28 different countries were included. Investigation of the number of studies and patients from a geographical perspective showed that the majority of published literature from January-March 2020 to April-June 2020 was from Asia, though there was a temporal shift in published studies to Europe and the Americas. For each laboratory value, the proportion of studies that noted a statistically significant (p < 0.05) correlation with adverse clinical outcomes (e.g., mortality, disease severity) was tabulated. Results and conclusion Among frequently reported laboratory values, blood urea nitrogen was the most often reported predictor of mortality (91%); neutrophil-to-lymphocyte ratio was the most frequent statistically significant laboratory parameter in predicting disease severity (96%). This review highlights the temporal progression of laboratory value frequencies, as well as potentially distinct utilities of different markers for clinical outcomes of COVID-19. Future research pathways include using this collected data for focused quantitative meta-analyses of particular laboratory values correlated with clinical outcomes of mortality and disease severity.