Table 3. p-values of the body mass index among different groups.

	Healthy	Mild	Moderate	Severe
Healthy	/	0.0018	<10−17	<10−27
Mild	0.0018	/	<10−8	<10−15
Moderate	<10−17	<10−8	/	<10−4
Severe	<10−27	<10−15	<10−4	/