Table 1 Demographic characteristics of individuals in the Minnesota Adolescent Community Cohort (MACC) sample, by clean indoor air (CIA) policy status
Individual characteristicsTotal, (n = 4233)Policy,† (n = 1028)No policy, (n = 3205)
Age at baseline:
1114.1% (597)12.8% (132)14.5% (465)
1217.1% (723)16.4% (169)17.3% (554)
1317.2% (729)17.7% (182)17.1% (547)
1417.2% (728)18.3% (188)16.8% (540)
1517.2% (730)17.0% (175)17.3% (555)
1617.2% (726)17.7% (182)17.0% (544)
Female51.0% (2151)50.6% (520)51.1% (1631)
Race/ethnicity:**
Caucasian84.9% (3565)71.7% (733)89.1% (2832)
African–American5.0% (210)14.9% (152)1.8% (58)
Native American2.6% (109)2.4% (24)2.7% (85)
Asian2.4% (99)4.7% (48)1.6% (51)
Hispanic/Latino2.6% (107)3.0% (31)2.4% (76)
Other2.6% (110)3.3% (34)2.4% (76)
Parental smoking at baseline:
Mother24.7% (989)25.0% (972)24.6% (746)
Father25.7% (916)25.2% (790)25.9% (717)
Home smoking policy:
In 2000‡63.3% (2265)63.3% (2265)
In 200678.1% (2548)76.1% (582)78.7% (1966)
Region of residence at baseline:**
Rural51.3% (2170)10.7% (110)64.3% (2060)
Suburban35.3% (1496)42.7% (439)33.0% (1057)
Urban13.4% (567)46.6% (479)2.7% (88)
Friend smoking:
At baseline‡39.2% (1423/3627)39.2% (1423/3627)
At 5-year follow-up58.4% (1915/3277)56.3% (432/767)59.1% (1483/2510)
Monthly smoking:
At baseline‡12.4% (449/3629)12.4% (449/3629)
At 5-year follow-up28.6% (929/3249)28.3% (215/760)28.7% (714/2489)
Weekly smoking:
At baseline‡8.0% (291/3625)8.0% (291/3625)
At 5-year follow-up22.4% (728/3244)22.4% (170/758)22.5% (558/2486)
  • *p<0.05, **p<0.01; †policy defined as any local clean indoor air policy in the city of residence by the end of the study period; ‡there were no CIA policies in effect in Minnesota in 2000 (baseline), therefore self-reported variables are not reported.