Weighted percentage difference in cost of smoking for sociodemographics and cost-minimising strategies from GAM, stratified by social grade
| Social grade | P value for interaction, high vs low | ||||
| Low (n=7032) | Middle (n=8138) | High (n=1797) | |||
| 100β with 95% CI | 100β with 95% CI | P value for interaction, middle vs low | 100β with 95% CI | ||
| Age | |||||
| Per 10 years increase | −0.23 (−1.04 to 0.59) | −0.18 (−0.65 to 1.00) | 0.27 (−1.65 to 2.19) | ||
| Gender | |||||
| Male | ref | ref | ref | ||
| Female | 0.54 (2.10 to 3.18) | 0.17 (−2.44 to 2.78) | −1.55 (−7.56 to 4.46) | ||
| Factory-made cigarette consumption | |||||
| Per 10 cigarettes decrease | −11.70 (−11.41 to −11.98) | −13.20 (−12.93 to −13.47) | <0.001 | −15.36 (−14.74 to −15.98) | <0.001 |
| RYO cigarette consumption | |||||
| Per 10 cigarettes decrease | −4.95 (−4.68 to −5.21) | −6.15 (−5.84 to −6.45) | 0.007 | −7.90 (−7.10 to −8.70) | 0.004 |
| Use of illicit sources | |||||
| No use of illicit sources in last 6 months | ref | ref | ref | ||
| Used illicit sources in last 6 months | −12.25 (−16.72 to −7.78) | −7.11 (−12.02 to −2.21) | 0.028 | −5.63 (−19.09 to 7.84) | 0.078 |
| Cross-border purchase | |||||
| No cross-border purchase in last 6 months | ref | ref | ref | ||
| Cross-border purchase in last 6 months | −13.01 (−19.03 to −6.72) | −9.99 (−14.46 to −5.53) | 0.264 | −7.24 (−15.80 to 1.33) | 0.053 |
All models were adjusted for all variables in the table.
GAM, generalised additive models; RYO, roll -your-own.