PMID- 33276312 OWN - NLM STAT- MEDLINE DCOM- 20210423 LR - 20210423 IS - 1873-6750 (Electronic) IS - 0160-4120 (Linking) VI - 146 DP - 2021 Jan TI - Remote sensing metrics to assess exposure to residential greenness in epidemiological studies: A population case study from the Eastern Mediterranean. PG - 106270 LID - S0160-4120(20)32225-X [pii] LID - 10.1016/j.envint.2020.106270 [doi] AB - INTRODUCTION/AIMS: Application of remote sensing-based metrics of exposure to vegetation in epidemiological studies of residential greenness is typically limited to several standard products. The Normalized Difference Vegetation Index (NDVI) is the most widely used, but its precision varies with vegetation density and soil color/moisture. In areas with heterogeneous vegetation cover, the Soil-adjusted Vegetation Index (SAVI) corrects for soil brightness. Linear Spectral Unmixing (LSU), measures the relative contribution of different land covers, and estimates percent of each over a unit area. We compared the precision of NDVI, SAVI and LSU for quantifying residential greenness in areas with high spatial heterogeneity in vegetation cover. METHODS: NDVI, SAVI, and LSU in a 300 m radius surrounding homes of 3,188 cardiac patients living in Israel (Eastern Mediterranean) were derived from Landsat 30 m spatial resolution imagery. Metrics were compared to assess shifts in exposure quartiles and differences in vegetation detection as a function of overall greenness, climatic zones, and population density, using NDVI as the reference method. RESULTS: For the entire population, the dispersion (SD) of the vegetation values detected was 60% higher when greenness was measured using LSU compared to NDVI: mean (SD) NDVI: 0.17 (0.05), LSU (%): 0.23 (0.08), SAVI: 0.12 (0.03). Importantly, with an increase in population density, the sensitivity of LSU, compared to NDVI, doubled: There was a 95% difference between the LSU and NDVI interquartile range in the highest population density quartile vs 47% in the lowest quartile. Compared to NDVI, exposures estimated by LSU resulted in 21% of patients changing exposure quartiles. In urban areas, the shift in exposure quartile depended on land cover characteristics. An upward shift occurred in dense urban areas, while no shift occurred in high and low vegetated urban areas. CONCLUSIONS: LSU was shown to outperform the commonly used NDVI in terms of accuracy and variability, especially in dense urban areas. Therefore, LSU potentially improves exposure assessment precision, implying reduced exposure misclassification. CI - Copyright (c) 2020 The Authors. Published by Elsevier Ltd.. All rights reserved. FAU - Sadeh, Maya AU - Sadeh M AD - Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel. Electronic address: maya.sadeh@gmail.com. FAU - Brauer, Michael AU - Brauer M AD - School of Population & Public Health, University of British Columbia, Canada. FAU - Dankner, Rachel AU - Dankner R AD - Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler School of Medicine, Tel Aviv University, Ramat Aviv, Israel; Unit for Cardiovascular Epidemiology, the Gertner Institute for Epidemiology and Health Policy Research, Sheba Medical Center, Tel Hashomer, Israel. FAU - Fulman, Nir AU - Fulman N AD - Department of Geography and Human Environment, Porter School of the Environment and Earth Sciences, Faculty of Exact Sciences, Tel Aviv University. FAU - Chudnovsky, Alexandra AU - Chudnovsky A AD - AIR-O Lab, Porter School of Environment and Geosciences, Faculty of Exact Sciences, Department of Geography and Human Environment, Tel Aviv University, Israel. Electronic address: achudnov@tauex.tau.ac.il. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20201202 PL - Netherlands TA - Environ Int JT - Environment international JID - 7807270 SB - IM MH - *Benchmarking MH - Epidemiologic Studies MH - Humans MH - Israel MH - Population Density MH - *Remote Sensing Technology OTO - NOTNLM OT - Epidemiological studies OT - Exposure assessment OT - Linear spectral unmixing OT - Normalized difference vegetation index (NDVI) OT - Residential greenness OT - Spectral mixture analysis EDAT- 2020/12/05 06:00 MHDA- 2021/04/24 06:00 CRDT- 2020/12/04 20:14 PHST- 2020/07/12 00:00 [received] PHST- 2020/10/20 00:00 [revised] PHST- 2020/11/05 00:00 [accepted] PHST- 2020/12/05 06:00 [pubmed] PHST- 2021/04/24 06:00 [medline] PHST- 2020/12/04 20:14 [entrez] AID - S0160-4120(20)32225-X [pii] AID - 10.1016/j.envint.2020.106270 [doi] PST - ppublish SO - Environ Int. 2021 Jan;146:106270. doi: 10.1016/j.envint.2020.106270. Epub 2020 Dec 2.