Table I.

General data of subjects in the three groups.

	Groups
Items	Control	Mild pneumonia	Severe pneumonia
Case no.	92	90	95
Sex
Male	46	46	48
Female	46	44	47
Average age (years)	3.296	3.316	3.350
Fever (n)	0	90	95
Cough (n)	0	90	95
Abnormal findings in chest X-ray radiography (n)	0	90	95
Positive responses in MP antibody test (n)	0	90	95

MP, Mycoplasma pneumoniae.