Table 2.
Prevalence, factor loadings and criterion response parameters: DSM-IV nicotine dependence criteria and cigarette use criteria.
| Past-year nicotine dependence (D)and cigarette use (C) criteria | Prevalence (%) | Factor loadings |
Model with cigarette use criterion ‘one pack a day’ |
Model with cigarette use criterion ‘med half a pack a day’ |
Model with cigarette use criterion ‘med quarter-pack a day’ |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| With ‘ack a day’ | With ‘half a pack a day’ | With ‘quarter a pack a day’ | Two-parameter model |
Rasch model | Two-parameter model |
Rasch model | Two-parameter model |
Rasch Model | |||||
| Discrimination (a), estimate a (S.E.) | Severity (b), estimate b (S.E.) | Severity (b), estimate b (S.E.) | Discrimination (a), estimate a (S.E.) | Severity (b), estimate b (S.E.) | Severity(b), estimate b (S.E.) | Discrimination (a), estimate a (S.E.) | Severity (b), estimate b (S.E.) | Severity (b), estimate b (S.E.) | |||||
| Tolerance (D) | 14.32 | 0.782 | 0.776 | 0.771 | 1.90 (0.05) | 1.37 (0.03) | 1.50 (0.02) | 1.90 (0.05) | 1.37 (0.03) | 1.46 (0.02) | 1.90 (0.05) | 1.37 (0.03) | 1.43 (0.02) |
| Withdrawal (D) | 67.71 | 0.836 | 0.868 | 0.868 | 2.05 (0.05) | –0.67 (0.02) | –0.76 (0.02) | 2.15(0.06) | –0.66 (0.02) | –0.74 (0.02) | 2.14 (0.06) | –0.66 (0.02) | –0.72 (0.02) |
| Larger/longer (D) | 23.18 | 0.786 | 0.781 | 0.782 | 1.90 (0.05) | 0.95 (0.02) | 1.04 (0.02) | 1.92 (0.05) | 0.95 (0.02) | 1.01 (0.02) | 1.93 (0.05) | 0.94 (0.02) | 0.99 (0.02) |
| Quit/control (D) | 60.87 | 0.633 | 0.627 | 0.633 | 1.47 (0.03) | –0.46 (0.02) | –0.45 (0.02) | 1.46 (0.03) | –0.47 (0.02) | –0.44 (0.02) | 1.48 (0.03) | –0.46 (0.02) | –0.43 (0.02) |
| Time spent (D) | 20.54 | 0.718 | 0.708 | 0.705 | 1.76 (0.04) | 1.10 (0.02) | 1.16 (0.02) | 1.74 (0.04) | 1.10 (0.02) | 1.13 (0.02) | 1.74 (0.04) | 1.11 (0.02) | 1.11 (0.02) |
| Activities given up (D) | 8.11 | 0.522 | 0.517 | 0.515 | 1.50 (0.03) | 2.11 (0.04) | 2.06 (0.03) | 1.50 (0.03) | 2.11 (0.04) | 2.00 (0.03) | 1.50 (0.03) | 2.11 (0.04) | 1.96 (0.03) |
| Physical/Psychological problems (D) | 48.08 | 0.753 | 0.744 | 0.745 | 1.84 (0.04) | 0.01 (0.02) | 0.01 (0.02) | 1.83 (0.04) | 0.01 (0.02) | .003 (0.02) | 1.84 (0.04) | 0.01 (0.02) | .004 (0.02) |
| Consumed one pack a day(C) | 40.91 | 0.420 | - | - | 1.14 (0.02) | 0.23 (0.02) | 0.19 (0.02) | - | - | - | - | - | - |
| Consumed half a pack a day(C) | 66.15 | - | 0.520 | - | - | - | - | 1.31 (0.03) | –0.85 (0.03) | –0.74 (0.02) | - | - | - |
| Consumed quarter-pack a day (C) | 77.26 | - | - | 0.572 | - | - | - | - | - | - | 1.45 (0.03) | –1.27(0.03) | –1.16(0.02) |
| Bayesian Information Criterion (BIC) (smaller is better) | 80180.34 | 81068.56 | 78180.11 | 78819.68 | 75987.38 | 76439.04 | |||||||
| Comparative Fit Index (CFI) | 0.955 | 0.948 | 0.952 | ||||||||||
| Tucker Lewis Index (TLI) | 0.968 | 0.963 | 0.966 | ||||||||||
| Root mean squared error of approximation (RMSEA) | 0.068 | 0.075 | 0.073 | ||||||||||