Table 1.

Inclusion criteria for studies

Population	Adult men (≥ 18 years at diagnosis)
Exposure	Former or current employment in occupational groups with known heavy physically demanding strain where results on the association between occupational strain and development of HOA were reported in at least three studies
Comparison	Occupational groups without heavy occupational workload
Endpoints	Diagnosis of HOA due to occupational strain based on •clinical and radiological criteria (American College of Rheumatology criteria [14] or radiological scoring systems according to Kellgren and Lawrence [16]) •total hip replacement subscales measuring hip pain, stiffness or reduced physical function •hip pain •reported cases with the diagnosis HOA in register data without further information including resulting disability, pension or sick leave Exclusion of studies with HOA due to non-occupational strains (e.g., due to sport, hip dysplasia or other hip deformities)
Study design	Full-text publications in German or English language from 1990 until today of •cohort studies •case–control studies or analysis of data from registry data •cross-sectional studies with relevant data of an exposure to occupations for ≥ 10 years to assure a causal relationship