Table 3

HRs* and 95% CIs for incident carpal tunnel syndrome

			HR (95% CI)
			Continuous exposure	Dichotomous exposure†	Trichotomous exposure‡
Type	Assessment method	Exposure	Per 1-unit increase	(High vs low)	(High vs low)	(Medium vs low)
Force intensity	Observed	Observer peak Borg	1.16 (1.09 to 1.25)	1.38 (1.06 to 1.80)	2.10 (1.47 to 3.00)	1.75 (1.30 to 2.35)
	O*NET	Dynamic strength	1.60 (1.28 to 1.99)	1.64 (1.20 to 2.24)	1.72 (1.06 to 2.79)	1.53 (1.05 to 2.23)
	O*NET	Static strength	1.38 (1.17 to 1.63)	1.20 (0.79 to 1.83)	1.31 (0.88 to 1.95)	1.29 (0.78 to 2.15)
Repetition	Observed	Observer HAL	1.08 (0.96 to 1.22)	1.28 (0.90 to 1.83)	1.32 (0.88 to 2.00)	1.42 (0.96 to 2.11)
	O*NET	Time spent making repetitive motions	1.58 (1.25 to 2.00)	1.42 (1.02 to 1.98)	1.63 (1.12 to 2.37)	1.30 (0.84 to 2.01)
	O*NET	Time spent using your hands to handle, control, or feel objects	1.78 (1.42 to 2.24)	1.36 (0.99 to 1.87)	1.78 (1.22 to 2.61)	1.50 (1.06 to 2.12)
Forceful exertions (duration/rate)	Observed	% duration forceful exertions	1.01 (1.01 to 1.02)	1.74 (1.38 to 2.2)	1.80 (1.33 to 2.43)	1.47 (1.12 to 1.93)
	Observed	Repetitions/minute forceful exertions	1.02 (1.01 to 1.02)	1.38 (0.98 to 1.95)	1.90 (1.31 to 2.75)	1.15 (0.75 to 1.77)
	O*NET	Handling and moving objects	1.30 (1.13 to 1.48)	1.78 (1.37 to 2.31)	1.80 (1.33 to 2.43)	1.47 (1.12 to 1.93)

*Cox proportional hazards regression models with robust sandwich estimators, adjusted for age, gender, body mass index and study site.
†Exposures are dichotomised at the median.
‡Exposures are trichotomised at 33rd and 67th percentiles.
HAL, hand activity level; O*NET, Occupational Network.