Table 4.

Determinants for perceived usability.

Determinant			Univariable analysis			Multivariable analysis
Reference group	Determinant	ba (95% CI)		P value	b (95% CI)		P value
Age per year	Age	-.067 (-0.114 to -0.021)		.004	-.094 (-1.147 to -0.042)		<.001
Male	Gender	1.322 (-0.234 to 2.878)		.10	-.153 (-1.806 to 1.500)		.86
Low education	Intermediate education	1.275 (-1.224 to 3.774)		.32	1.262 (-1.189 to 3.712)		.31
	High education	-1.992 (-4.302 to 0.318)		.09	-2.512 (-4.791 to -0.232)		.03
No chronic disease	Diabetes	-.377 (-2.692 to 1.939)		.80	.347 (-2.053 to 2.747)		.78
	Asthma or COPDb	-3.399 (-6.337 to -.416)		.02	-3.630 (-6.545 to -0.715)		.02
	Cardiovascular disease	-.286 (-2.668 to 2.096)		.81	.890 (-1.576 to 3.357)		.48

^ab: unstandardized beta value.

^bCODP: chronic obstructive pulmonary disease.