Association between Family Structure and Physical Activity of Chinese Adolescents

Table 1

Descriptive information for study variables ().

Variables	M or (%)	SD	Range
MVPA time	22 min/day	14.5	4–89
Age (in years)	12	1.2	10–16
Gender
Boys	317 (51.9%)
Girls	295 (48.1%)
Grade
Grade 5	158 (25.8%)
Grade 6	136 (22.2%)
Grade 7	178 (29.1%)
Grade 8	140 (22.9%)
SES
Low	116 (18.9%)
Middle	355 (58.0%)
High	141 (23.1%)