As well as organising and integrating public health information, the development of a common classification will promote consistency in describing public health, through the standardisation of definitions and terminology. This will improve data capture processes and the quality of reporting (e.g. in expenditure and performance reporting). Promoting consistency will increase the ability to compare public health information over time and across jurisdictions. 34 There is potential for a public health 33 Additional questions include other advocacy-type questions, such as: what is the relative expenditure on specific risk factors or diseases? What is the difference in expenditure on prevention of HIV/AIDS relative to other preventable diseases? Has health funding to preventive/promotive investments increased?. There are also boundary questions such as: can we describe the hospital interface with public health interventions (e.g. screening in hospitals)? Can we calculate expenditures in specific areas (e.g. product safety and protection, public health emergencies, education as a health promotive activity)? Competency questions can be used as a 'litmus test' to help determine whether the classification contains sufficient information to answer them, and whether the answers require a particular level of detail or representation of a particular area (Noy & McGuinness 2001: 5) . 34 Recent reporting of public health expenditures over several years has enabled such analyses for the first time (AIHW 2004b). classification to be used to improve jurisdictional public health financial processes (e.g. budgeting, resource allocation) and accounting systems (e.g. through developing systems that can apportion public health activities to cost centres or to aggregate Treasury outputs). 35