Use of Geocoding to Understand Variation in Neighborhood Socioeconomic Status in a Nationwide Occupational Cohort across Time, Space and Demographic Characteristics

摘要

Geocoding has been used in environmental epidemiology to understand geographically patterned exposures but has not been widely applied in occupational studies. We present the feasibility of geocoding a nationwide occupational cohort, the US Radiologic Technologists Study (USRT, N=146,021) to: (1) evaluate geocoding across time, (2) test precision of geocoding by rural (vs. urban) status and by neighborhood socioeconomic status (nSES), and (3) explore nSES distribution by some cohort demographic factors. We created a standardized nSES index, based on validated methods, for each census block-group in the US, at 3 time points, using 6 items from the U.S. Census (1990, 2000) and American Community Survey (2010): regionally-adjusted median household income and median housing value, % households with interest/income, % adults who completed high school, % adults who completed college, and % employed persons in managerial occupations. To link nSES to the cohort, we geocoded respondent addresses in 1992, 2003, 2010, to block-group of residence. Over 99% of addresses were geocoded; 76 to 86% were mapped to an address-specific block-group, while the rest were geocoded to a block-group of the zipcode centroid. Urban (vs. rural) addresses and those in the highest (vs. lowest) nSES quintile were more likely to be geocoded to an address-specific block-group (OR=4.6; 95%CI=4.5-4.7 and OR=6.4; 95%CI=6.1-6.7, respectively for 1992 addresses). Results of linear regression show higher nSES in 1990 was associated with USRT participants of female gender (3=0.22; 95%CI=0.20, 0.23), older age (3=0.003; 95%CI=0.002, 0.003), white race (3=0.37; 95%CI=0.35, 0.38) and more recent age-adjusted certification year (3= -0.018; 95%CI= -0.016, -0.019). Similar results were obtained for other years. This analysis indicates geocoding can describe neighborhood characteristics within the USRT which may be related to diseases linked to occupational exposures like cancer and cardiovascular disease.