TABLE 1.

Participants’ characteristics.

	Trained workers (n = 13)	Untrained workers (n = 27)	T statistics and df	p-values
Age (years)	35.8 ± 10.5	37.9 ± 10.0	F(1,38) = 0.36	p = 0.648
Gender (female/male)	11/2	13/14	χ2 = 0.03 (φ = −0.35)	p < 0.05
Assembly time (s)	23.7 ± 3.4	44.3 ± 10.8	F(1,38) = 44.26	p < 0.001
Accuracy (%)*	3 errors = 0%	3 errors = 3.7%	χ2 = 5.38 (φ = 0.38)	p = 0.146
	2 errors = 0%	2 errors = 14.8%
	1 error = 16.7%	1 error = 33.3%
	0 error = 83.3%	0 error = 48.1%
Manual hand dexterity: pegboard test (s)	38.5 ± 6.7	37.4 ± 5.1	F(1,38) = 0.33	p = 0.568

*Number of mistakes while tightening screws (range 0–6 screws = % of subjects within the group).