Table 3.
Estimated percentage point changes in mean cigarette consumption per day as a function of e-cigarette use and NRT use among smokers for temporary abstinence from November 2006 to March 2016, based on ARIMAX models
| All users of nicotine replacement | Only daily users of nicotine replacement | |||||
| Percentage change per 1 % change in the exposure (95% CI) P values | ||||||
| Use of e-cigarettes for temporary abstinence (immediate impact) |
−0.010 (−0.024 to 0.005) 0.150 |
−0.011 (−0.027 to 0.004) 0.146 |
−0.010 (−0.024 to 0.004) 0.159 |
−0.011 (−0.026 to 0.003) 0.135 |
||
| NRT use for temporary abstinence (immediate impact) |
0.023 (−0.016 to 0.062) 0.241 |
0.022 (−0.020 to 0.063) 0.303 |
0.006 (−0.015 to 0.028) 0.563 | 0.006 (−0.016 to 0.028) 0.585 |
||
| Mass media expenditure (immediate impact) |
<0.001 (−0.001 to 0.001) 0.873 |
<0.001 (−0.001 to 0.001) 0.942 | ||||
| Total percentage change due to the exposure (95% CI) P values | ||||||
| Smoking ban (pulse effect) |
0.017 (−0.069 to 0.103) 0.696 |
0.014 (−0.071 to 0.099) 0.750 |
||||
| Increase in age-of-sale (pulse effect) |
−0.036 (−0.122 to 0.050) 0.415 |
−0.040 (−0.125 to 0.044) 0.350 |
||||
| Move to local authority control (pulse effect) |
−0.016 (−0.102 to 0.071) 0.721 |
−0.026 (−0.111 to 0.060) 0.556 |
||||
| Licensing for NRT for harm reduction (pulse effect) |
0.023 (−0.067 to 0.114) 0.615 |
0.019 (−0.070 to 0.108) 0.670 |
||||
| NICE guidance on harm reduction (pulse effect) |
−0.021 (−0.106 to 0.065) 0.638 |
−0.030 (−0.116 to 0.055) 0.483 |
||||
| Best fitting model | ARIMAX(0,1,1)(0,0,0)12 | ARIMAX(0,1,1)(0,0,0)12 | ARIMAX(0,1,1)(0,0,0)12 | ARIMAX(0,1,1)(0,0,0)12 | ARIMAX(0,1,1)(0,0,0)12 | ARIMAX(0,1,1)(0,0,0)12 |
| Non-seasonal AR P values | NA | NA | NA | NA | NA | NA |
| Non-seasonal MA P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Seasonal AR P values | NA | NA | NA | NA | NA | NA |
| Seasonal MA P values | NA | NA | NA | NA | NA | NA |
| R2 | 0.65 | 0.65 | 0.65 | 0.65 | 0.64 | 0.65 |
| Bayes factor e-cigarette (0.009 (0.1)) | 1.01 (0.59) | 1.94 (0.38) | 1.97 (0.35) | 2.15 (0.41) | ||
| Bayes factor NRT (0.009 (0.1)) | 0.15 (0.02) | 0.69 (0.11) | 1.05 (0.18) | 0.61 (0.08) | ||
An AR(1) means that the value of a series at one point in time is the sum of a fraction of the value of the series at the immediately preceding point in time and an error component; an MA(1) means that the value of a series at one point in time is a function of a fraction of the error component of the series at the immediately preceding point in time and an error component at the current point in time.
AR, autoregressive; ARIMAX, Autoregressive Integrated Moving Average with Exogeneous Input; MA, moving average; NA, not applicable; NICE, National Institute for Health and Care Excellence; NRT, nicotine replacement therapy.