Income level** | Mean sodium purchases (mg/day per capita)† | ||
Current | Australian targets applied | Mean difference (targets applied−current) | |
Low | 491 | 437 | −54 |
Middle | 437 | 388 | −50 |
High | 409 | 362 | −47 |
All groups | 443 | 393 | −50 |
*The OECD-modified equivalence scale was applied to calculate equivalised household income (adjusting for household size and age of household members).34 35 Three income groups (low, middle and high) were then generated by splitting households into three groups of approximately equal numbers. The three household income groups (low: <$A28 667 per year, middle: $A28 846–52 778 per year and high: >$A53 125 per year) had mean incomes that were comparable to equivalised incomes for the Australian population in 2016 (low income: ≤30th percentile ≤$A33 020; middle-income: 30–60th percentile: $A33 021–51 324, high-income: >60th percentile ≥$A51 325).54
†SE for sodium purchases (mg/day per capita) not displayed as SE ≤0.1 for each mean value. Low income households purchased significantly higher sodium per capita in 2018 compared with middle-income households (mean difference, −54 mg/day, 95% CI −74 to −34 mg/day, p<0.001) and high-income households (−82 mg/day, 95% CI −102 to −62 mg/day, p<0.001).