Table 6.

Selection of variables in machine learning and conventional methods for osteoporosis risk of hip, neck and lumbar

Variables	Machine learning method				Conventional method
	SVM	RF	ANN	LR	OST	ORAI	SCORE	OSIRIS
Age	o	o	o	o	o	o	o	o
Height	o	o	o
Weight	o	o	o	o	o	o	o	o
Body mass index	o	o	o
Waist circumference		o
Pregnancy		o	o
Duration of menopause		o	o
Duration of breastfeeding	o	o	o	o
Estrogen therapy	o					o	o	o
Hyperlipidemia	o	o		o
Hypertension	o	o
Fracture history			o				o	o
Osteoarthritis	o	o	o	o
Rheumatoid arthritis							o
Diabetes mellitus	o	o	o	o

SVM support vector machines, RF random forests, ANN artificial neural networks, LR logistic regression, OST osteoporosis self-assessment tool, ORAI osteoporosis risk assessment instrument; SCORE simple calculated osteoporosis risk estimation, OSIRIS osteoporosis index of risk