Table 2 Characteristics of eligible case-control studies on the association between physically demanding occupations and the development of osteoarthritis

Patients of an orthopaedic practice

N=418 (220/198)

Response cases: 60 %, control: n.d.

Age (range) of cases: 30 % - > 60 years with younger controls

Women (%): 189 (45 %)^a

Nurses and kindergarten teacher: 18 (100 %)^a

Health care: 10 (100 %)^a

Retail worker: 27 (71 %)^a

Workers in hotels, gastronomy and households: 22 (61.1 %)^a

Occupations in textile industry: 13 (100 %)^a

Cleaner: 8 (61.5 %)^a

Hairdresser: 6 (100 %)^a

All patients and their first-degree relatives ≥ 60 years

Response cases: 33 %

N= 2490 (1408/1082)

Age: cases: 71-75/ controls: 71 years

Women (%): 1424 (832/592) (57.2 %)

Managers and professionals: 115 (54.5 %)

Farmer: 242^a (46.7 %)^a

Technicians and associate professionals: 196^a (63.8 %)^a

Service and shop worker: 246^a (78.8 %)^a

Craft worker: 196^a (45.7 %)^a

Operator and unskilled labour: 162 (53 %)