Table 2.

Association between positive questionnaire in 1993–1994 and upper extremity musculoskeletal disorders (UEMSD) diagnosed by physical examination in 1996–1997 (cases), stratified on age.

	All workers								Workers without any UEMSD diagnosed in 1993–1994
	Age <40 years old				Age ≥ 40 years old				Age < 40 years old				Age ≥ 40 years old
	N*	Number of cases (1996–1997)	Proportion %	p=**	N*	Number of cases (1996–1997)	Proportion %	p=**	N*	Number of cases (1996– 1997)	Proportion %	p=**	N*	Number of cases (1996–1997)	Proportion %	p=**
Negative questionnaire in 1993–1994	140	61	43.6	<0.0001	16	8	50.0	<0.01	120	46	38.3	<0.05	14	6	42.9	ns
Positive questionnaire in 1993–1994	338	265	78.4		104	89	85.6		34	20	58.8		9	6	66.7
Total	478	326	68.2		120	97	80.8		154	66	42.9		23	12	52.2

^*N=Number of subjects

^**Chi² or Fisher exact tests