Table 2

Treatment effects by study

Follow-up time pointAuthorsYearControlMIDifferenceOR95% CI
% (n) abstinent% (n) abstinent
4–8 weeksStotts et al35200221.5% (135)20.1% (134)−1.4%0.92(0.51 to 1.66)
Borrelli et al3620059.0% (144)9.3% (129)0.3%1.03(0.45 to 2.35)
Brown et al37200310.7% (75)11.2% (116)0.5%1.06(0.42 to 2.69)
Okuyemi et al3820075.6% (107)6.1% (66)0.5%1.09(0.29 to 4.00)
Kelly and Lapworth32200615.4% (26)20.0% (30)4.6%1.38(0.34 to 5.53)
Glasgow et al3920006.9% (576)10.2% (578)3.3%1.52(1.00 to 2.32)
Helstrom et al4020075.6% (36)8.9% (45)3.3%1.66(0.29 to 9.61)
Colby et al4120050.0% (42)2.3% (43)2.3%Infinite*Undefined
10–12 weeksIngersoll et al42200755.6% (18)31.8% (22)−23.8%0.37(0.10 to 1.36)
Stein et al4320068.3% (192)5.8% (191)−2.5%0.67(0.30 to 1.49)
Haug et al2220040.0% (33)0.0% (30)0.0%1*Undefined
Wakefield et al4420046.3% (63)6.8% (74)0.5%1.07(0.27 to 4.16)
Kelly and Lapworth32200615.4% (26)20.0% (30)4.6%1.38(0.34 to 5.53)
Colby et al45199810.0% (20)20.0% (20)10.0%2.25(0.36 to 13.97)
Baker et al4620066.0% (151)15.0% (147)9.0%2.78(1.23 to 6.25)
Curry et al4720032.7% (147)8.3% (156)5.6%3.25(1.03 to 10.21)
Hokanson et al4820065.3% (57)15.8% (57)10.5%3.37(0.86 to 13.19)
McCambridge and Strang3320047.9% (63)25.0% (76)17.1%3.87(1.35 to 11.06)
Colby et al4120050.0% (42)4.7% (43)4.7%Infinite*Undefined
22–26 weeksAhluwalia et al29 (MI + placebo NRT)200615.4% (188)6.9% (189)−8.5%0.40(0.20 to 0.81)
Tappin et al3420008.0% (50)4.0% (50)−4.0%0.48(0.08 to 2.74)
Ahluwalia et al29 (MI + NRT)200618.0% (189)10.1% (189)−7.9%0.51(0.28 to 0.93)
Ruger et al4920088.0% (100)6.4% (110)−1.6%0.78(0.27 to 2.24)
Okuyemi et al3820079.3% (107)7.6% (66)−1.7%0.80(0.26 to 2.44)
Horn et al5020072.9% (34)2.4% (41)−0.5%0.82(0.05 to 13.70)
Tappin et al5120058.8% (411)7.4% (351)−1.4%0.83(0.49 to 1.41)
Smith et al30 (low-risk for relapse)200124.8% (121)22.0% (127)−2.8%0.86(0.48 to 1.55)
Hokanson et al48200610.5% (57)10.5% (57)0.0%1.00(0.30 to 3.31)
Hannover et alUnpub21.2% (433)21.9% (438)0.7%1.04(0.75 to 1.44)
Stein et al4320064.7% (192)5.2% (191)0.5%1.12(0.45 to 2.83)
Borrelli et al36200510.4% (144)11.6% (129)1.2%1.13(0.53 to 2.42)
Glasgow et al39200014.9% (576)18.3% (578)3.4%1.28(0.94 to 1.75)
Hyman et al31 (sequential tx for several health behaviours)200721.5% (93)27.1% (96)5.6%1.36(0.69 to 2.65)
Hyman et al31 (simultaneous tx for several health behaviours)200721.5% (93)29.3% (92)7.8%1.52(0.78 to 2.96)
Smith et al30 (high-risk for relapse)200112.7% (102)18.8% (101)6.1%1.59(0.74 to 3.41)
Helstrom et al4020075.6% (36)8.9% (45)3.3%1.66(0.29 to 9.61)
Kelly and Lapworth32200615.4% (26)23.3% (30)7.9%1.67(0.43 to 6.52)
Brown et al3720038.0% (75)12.9% (116)4.9%1.71(0.63 to 4.62)
McClure et al52200512.4% (137)19.6% (138)7.2%1.72(0.89 to 3.32)
Manfredi et al5320048.6% (547)14.7% (517)6.1%1.83(1.25 to 2.70)
Baker et al4620064.0% (151)9.5% (147)5.5%2.54(0.95 to 6.81)
Butler et al5419993.0% (266)8.1% (270)5.1%2.86(1.25 to 6.55)
Colby et al4120052.4% (42)9.3% (43)6.9%4.21(0.45 to 39.29)
Soria et al5520063.5% (86)18.4% (114)14.9%6.25(1.80 to 21.71)
Gariti et al5620020.0% (30)5.9% (34)5.9%Infinite*Undefined
Herman and Fahnlander5720030.0% (22)15.0% (20)15.0%Infinite*Undefined
52 weeksMcClure et al52200519.7% (137)18.1% (138)−1.6%0.90(0.49 to 1.65)
Hannover et alUnpub19.6% (433)18.5% (438)−1.1%0.93(0.66 to 1.30)
Smith et al30 (high-risk for relapse)200113.7% (102)12.9% (101)−0.8%0.93(0.41 to 2.09)
Smith et al30 (low-risk for relapse)200123.1% (121)23.6% (127)0.5%1.03(0.57 to 1.85)
Manfredi et al53200410.8% (547)11.4% (517)0.6%1.07(0.73 to 1.56)
Brown et al3720039.3% (75)13.8% (116)4.5%1.55(0.61 to 3.98)
Borrelli et al3620058.3% (144)12.4% (129)4.1%1.56(0.71 to 3.43)
Baker et al4620066.6% (151)10.9% (147)4.3%1.72(0.75 to 3.93)
Curry et al4720030.7% (147)1.9% (156)1.2%2.86(0.29 to 27.83)
Soria et al5520063.5% (86)18.4% (114)14.9%6.25(1.80 to 21.71)
  • * ORs in which the control abstinence rate is 0 were included in figure 1 by adding 0.25 to the cell; in actuality, they are undefined due to division by zero. The random rather than fixed intercept in the regression models accounted for such low control abstinence rates. ORs calculated before rounding abstinence rates.

  • 95% CIs obtained using Woolf's method.58

  • MI, motivational interviewing intervention; n, sample size; NRT, nicotine replacement therapy; tx, treatment.