TABLE 3.
Unadjusted estimates (% and 95% CI) of abstinence, overall and by arm, chi-square test with brief advice as the reference group
| Overall (N = 903) | BA (n = 128) | MI (n = 258) | RR (n = 257) | MI + RR (n = 260) | P value | |
|---|---|---|---|---|---|---|
| Primary outcome, point prevalence abstinence | ||||||
| ITT MNAR | 21.5% (18.8, 24.2) | 10.9% (5.5, 16.3) | 15.5% (11.1, 19.9) | 27.2% (21.8, 32.7) | 26.9% (21.5, 32.3) | <0.0001 |
| ITT MAR | 26.1% (25.5, 26.7) | 12.8% (11.7, 13.9) | 18.6% (17.7, 19.6) | 33.9% (32.8, 35.1) | 32.3% (31.2, 33.4) | <0.0001 |
| Secondary outcome, prolonged abstinence | ||||||
| ITT MNAR | 18.8% (16.3, 21.4) | 9.4% (4.3, 14.4) | 13.9% (9.7, 18.2) | 24.1% (18.9, 29.4) | 23.1% (17.9, 28.2) | 0.0002 |
| ITT MAR | 22.8% (22.3, 23.4) | 11.2% (10.1, 12.3) | 16.9% (16.0, 17.8) | 29.9% (28.8, 31.0) | 27.5% (26.4, 28.6) | <0.0001 |
Abbreviations: BA, brief advice (comparison); ITT MAR, intention to treat missing at random; ITT MNAR, intention to treat missing not at random; MI, motivational interviewing; RR, rate reduction; RR + MI, motivational interviewing + rate reduction.