Table 2 Modelled student and school level characteristics associated with assent to data linkage
|  |  | Data linkage sub-sample (n = 18,956) |  | ||
|---|---|---|---|---|---|
| Â | Â | Bivariate models | Multivariable model | ||
| Â | Consented to data linkage, n/N (%) | OR (95% CIs) | Wald test | AOR (95% CIs)c | Wald test |
Student-level | |||||
 Gender | |||||
  Male | 4654/9545 (48.8) | 1.00 |  | 1.00 |  |
  Female | 4465/9064 (49.3) | 1.01 [0.95, 1.07] |  | 1.02 [0.95, 1.08] |  |
  Did not state | 113/347 (32.6) | 0.52 [0.41, 0.65] | X2(2) = 31.55 | 0.65 [0.50, 0.86] | X2(2) = 10.26 |
 School grade | |||||
  Year 7 | 1980/3787 (52.3) | 1.00 |  | 1.00 |  |
  Year 8 | 2125/4122 (51.6) | 0.97 [0.89, 1.07] |  | 0.99 [0.90, 1.09] |  |
  Year 9 | 1969/4347 (45.3) | 0.74 [0.68, 0.81] |  | 0.76 [0.69, 0.83] |  |
  Year 10 | 1696/3500 (48.5) | 0.88 [0.80, 0.96] |  | 0.93 [0.84, 1.03] |  |
  Year 11 | 1462/3200 (45.7) | 0.77 [0.70, 0.85] | X2(4) = 67.55 | 0.81 [0.73, 0.90] | X2(4) = 51.32 |
 Weekly smoker | |||||
  No | 8794/17,656 (49.8) | 1.00 |  | 1.00 |  |
  Yes | 219/571 (38.4) | 0.66 [0.55, 0.78] |  | 1.02 [0.81, 1.30] |  |
 Past month cannabis use | |||||
  No | 8848/17,799 (49.7) | 1.00 |  | 1.00 |  |
  Yes | 279/699 (39.9) | 0.67 [0.57, 0.78] |  | 0.86 [0.70, 1.06] |  |
 Ever truant | |||||
  No | 6988/13,666 (51.1) | 1.00 |  | 1.00 |  |
  Yes | 2007/4455 (45.1) | 0.78 [0.73, 0.84] |  | 0.91 [0.85, 0.99] |  |
 Ever excluded | |||||
  No | 8633/17,216 (50.2) | 1.00 |  | 1.00 |  |
  Yes | 511/1304 (39.2) | 0.65 [0.58, 0.74] |  | 0.82 [0.72, 0.94] |  |
SWEMWBS (sd.) | 22.415 (4.23) | 1.03 [1.03, 1.04] | Â | 1.02 [1.01, 1.03] | Â |
FAS (sd.) | 9.457 (2.29) | 1.03 [1.02, 1.05] | Â | 1.02 [1.01, 1.04] | Â |
School-level | |||||
 Mean FAS (sd.) | 9.397 (0.50) | 1.38 [1.04, 1.85] |  | 1.36 [1.02, 1.83] |  |
ICC – constant only | 0.071 |  |  |  |  |
ICC – Student level | 0.071 |  |  |  |  |
ICC – Level 1 & 2 variables | 0.064 |  |  |  |  |