Table 1.

Basic characteristics of study subjects

OA phenotype	Number		Gender (%women)			Age (mean)			BMI a (mean)
	Cases	Controls	Cases	Controls	P -value	Cases	Controls	P -value	Cases	Controls	P -value
ROA One definite osteophyte (original K ≥2)	371	467	84%	80%	0.1974	62.22	61.23	0.023	25.55	24.28	1.3 × 10-7

BMI^a: body mass index.