Table 2. The factors involved in the accuracy of pen operation were extracted by multiple regression analyses (n=35).

Model	Variable	Unstandardized coefficients		Standardized Coefficients	p-value	Adjusted R2
		B	SE	β
‘Strong’ model	Degree of variation in pen pressure	448.38	152.86	0.62	0.0064**	0.28
	Writing speed	1,003.05	291.25	0.52	0.0017**
	Range of index finger PIP flexion	23.75	13.13	0.28	0.0805
	Pen pressure	−2,341.34	1,342.13	−0.36	0.0913
‘Careful’ model	Degree of variation in pen pressure	366.30	114.22	0.47	0.0031**	0.28
	Writing speed	872.20	446.76	0.29	0.0600
	Range of palmar flexion and dorsiflexion	−33.75	20.72	−0.24	0.1133

PIP: proximal interphalangeal.

**p<0.01.