RT Journal Article SR Electronic T1 Commentary: methodological approaches to understanding mechanisms and ‘what if’ questions in occupational health research JF Occupational and Environmental Medicine JO Occup Environ Med FD BMJ Publishing Group Ltd SP 524 OP 525 DO 10.1136/oemed-2023-109085 VO 80 IS 9 A1 Smith, Peter M YR 2023 UL http://oem.bmj.com/content/80/9/524.abstract AB