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Table 1 Definitions of validity terms

From: A step-by-step approach to improve data quality when using commercial business lists to characterize retail food environments

Term Definition
Count accuracy Number of outlets is neither an under- nor over-count
Classification accuracy Business type is correctly identified
Locational accuracy Geographic coordinates are accurate within an acceptable level of precision
True positive (TP) Outlet present in business list and observed on the ground
False positive (FP) Outlet present in business list and not observed on the ground
True negative (TN) Outlet not present in business list and not observed on the ground
False negative (FN) Outlet not present in business list and observed on the ground
Sensitivity Proportion of observed outlets that are included in the business list: (TP)/(TP + FN)
Positive predictive value (PPV) Likelihood that an outlet present in the business list is observed: (TP)/(TP + FP)
Concordance Proportion of outlets both present in the business list and observed out of all outlets either in the business list or observed: (TP)/(TP + FP + FN)