Table 2.

Measures of children's exposure to environmental tobacco smoke in families with a young child (<4 years old) and a mother who smoked who received either three months of counselling or standard advice to reduce smoking in the presence of the child. Values are geometric means (interquartile ranges) unless stated otherwise

VariableBaselineTime 3 months (after counselling)12 months
Reported exposure to environmental tobacco smoke (No of cigarettes/week)
Exposure from mothers in home:
Counselled families27.30 (32.91)4.47 (26.11)3.66 (28.08)
Control families24.56 (31.03)12.08 (33.09)8.38 (45.99)
Relative value for counselled group v controls (% (95% CI))*32.8 (26.3 to 39.3)41.2 (34.2 to 48.3)
Total environmental exposure:
Counselled families51.30 (73.43)12.99 (42.94)8.60 (44.15)
Control families50.68 (63.68)26.28 (59.79)19.23 (66.91)
Relative value for counselled group v controls (% (95% CI))*50.0 (42.8 to 57.2)45.7 (38.4 to 53.0)
Urine cotinine concentration (ng/ml)
Counselled families10.93 (17.29)12.65 (12.12)10.47 (24.28)
Control families9.43 (13.28)13.88 (18.00)17.47 (21.61)
Relative value for counselled group v controls (% (95% CI))*84.2 (79.0 to 89.4)55.6 (48.2 to 63.0)
  • * Means were adjusted for baseline levels to calculate relative values.