Table 1 Minor revisions to the initial diet pricing tools and methods

Added bottled water, olive oil, and relatively healthy pre-made “convenience” foods, such as sandwiches and cooked chicken, to the healthy (recommended) diet pricing tools

To enhance comparability with the current (unhealthy) diet pricing tools, that include comparable, but less healthy, options

Further aggregated nutritionally similar products with similar utility in both diet pricing tools (for example, ‘cabana’ and ‘bratwurst’ were grouped with ‘sausages’)

To minimize the number of items to be priced in-store to reduce survey burden and cost

Included the same food groupings in the healthy food component of both current and healthy diet pricing tools

To simplify data collection, comparison between current and healthy diets and interpretation of results

Adjusted the diet of the 8 year old girl (who was the oldest in her age/gender group) from the base Foundation Diets levels, according to the prescribed methods of Total Diet modelling to inform the 2013 revision of the Australian Guide to Healthy Eating of the Australian Dietary Guidelines [33]

To ensure adequate energy content of the constructed healthy (recommended) diet of the 8 year old girl in the reference household

Adjusted median household income at Statistical Area Level 2 (SA2) level by relevant wage price index; clarified that available data sets at SA2 level provide median gross (i.e. not disposable) household income

To incorporate the effect of inflation. Median household income at sub-national (area) level is readily available from published government sources, so has been used frequently in calculation of food affordability in Australia [13]. However, published median household income data at area level reflects gross (total) income and has not been adjusted for essential expenditures such as taxation, to reflect disposable household income; results should be interpreted accordingly.

Included a third option for estimating median disposable household income at the national level, for use in future national diet price and affordability surveys.

To enhance comparability with low (minimum) disposable income household income, that is also calculated at the national level.

Median disposable household income is available only at national level currently; however data may be available at state/territory level in the future.