Lung Cancer Results. Odds ratios are relative to the whole study area. a) Adjusted, no latency. b) Adjusted, 15 years of latency. Increasing latency increases magnitude of hot and cold spots. c) Crude, 15 years of latency. Difference from the adjusted map indicates spatial confounding. The crude and adjusted maps have the same optimal span. d) Adjusted, 15 years of latency. Black contour lines denote areas of significantly increased and decreased risk at the 0.05 level. e) Adjusted, 15 years of latency. Restriction to residences of longest duration greatly changes the map compared to results for all residences even when the same span is used (0.3). f) Use of the optimal span (0.95) for the restricted analysis produces a very flat map.