Reported symptoms associated with nicotine dependence by the third interview among 95 subjects who had at any time smoked at least once per month, including 42 subjects who had progressed to daily smoking
| Symptoms | Number of subjects reporting this as their first symptom, n=95 (%) | Total number of subjects reporting this symptom, n=95 (%) | Range of completed weeks from the onset of monthly smoking to the onset of the first symptom, n=60 | Median number of weeks from the onset of monthly smoking to the first symptom among 60 subjects reporting symptoms |
| Felt addicted | 18 (19) | 27 (28) | −39 to 202 | 18 |
| Strong urge to smoke | 14 (15) | 37 (39) | 1 to 199 | 28 |
| Feeling nervous, restless, or anxious | 14 (15) | 38 (40) | 1 to 202 | 46 |
| Difficulty concentrating | 13 (14) | 30 (32) | 2 to 209 | 32.5 |
| Feeling irritable | 11 (12) | 38 (40) | −19 to 202 | 38 |
| Unsuccessful quit attempt | 10 (11) | 27 (28) | −4 to 200 | 38 |
| Hard to refrain from smoking where it is not permitted | 6 (6) | 20 (21) | 0 to 202 | 33 |
| Feeling sad, blue or depressed | 6 (6) | 17 (18) | 1 to 202 | 30 |
| Smoke now because it is really hard to quit | 0 (0) | 16 (17) | 17 to 228 | 72.5 |