Physical work exposure matrix for use in the UK Biobank

UK Biobank (UKB) is a large prospective cohort capturing numerous health outcomes, but limited occupational information (job title, self-reported manual work and occupational walking/standing).

To create and evaluate validity of a linkage between UKB and a job exposure matrix for physical work exposures based on the US Occupational Information Network (O*NET) database.

Job titles and UK Standard Occupational Classification (SOC) codes were collected during UKB baseline assessment visits. Using existing crosswalks, UK SOC codes were mapped to US SOC codes allowing linkage to O*NET variables capturing numerous dimensions of physical work. Job titles with the highest O*NET scores were assessed to evaluate face validity. Spearman's correlation coefficients were calculated to compare O*NET scores to self-reported UKB measures.

Among 324 114 participants reporting job titles, 323 936 were linked to O*NET. Expected relationships between scores and self-reported measures were observed. For static strength (0-7 scale), the median O*NET score was 1.0 (e.g. audiologists), with a highest score of 4.88 for stone masons and a positive correlation with self-reported heavy manual work (Spearman's coefficient = 0.50). For time spent standing (1-5 scale), the median O*NET score was 2.72 with a highest score of 5 for cooks and a positive correlation with self-reported occupational walking/standing (Spearman's coefficient = 0.56).

While most jobs were not physically demanding, a wide range of physical work values were assigned to a diverse set of jobs. This novel linkage of a job exposure matrix to UKB provides a potentially valuable tool for understanding relationships between occupational exposures and disease.