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Table 2 Variables used for modelling hotspots of malaria infection using datasets describing the physical geography of Unguja, Zanzibar

From: Mapping hotspots of malaria transmission from pre-existing hydrology, geology and geomorphology data in the pre-elimination context of Zanzibar, United Republic of Tanzania

Variable Description Mean (range)
Dependent variables
Apr-Jun 2011 Binary malaria infection hotspot/non-hotspot (n = 49) for the wet season  
Jul-Sep 2011 Binary malaria infection hotspot/non-hotspot (n = 49) for the dry season  
Independent variables
Geology Geology type:  
M1: hard, dense crystalline Miocene limestone
M3: dense Miocene chalky rock
Q1: Quaternary tropical laterites
Q2: Quaternary limestone
Q2M1: mixture of Q2 and M1
Q2Q3M1: mixture of Q2, Q3 (lightly cemented Quaternary sandstone) and M1
Distance to streams Distance to perennial streams (m) 12251 (154–36096)
Distance to dolines Distance to dolines (m) 9746 (0–26685)
Infiltration Soil infiltration rate: 1 = low, 2 = medium, 3 = high  
Landcover Land cover type: B = bushland, C = cultivated, F = natural forest, M = mangrove, S = scrub, U = urban  
Elevation Elevation (m) above sea level 28.5 (8–99)
Slope Slope angle (°) 1.5 (0.3-4.5)
Condition Condition of health facility: 1 = Very Bad, 2 = Bad, 3 = Fair, 4 = Good, 5 = New