2.1.BACKGROUND

Modelling for Key Performance Indicators was undertaken using the General and Breast diagnostic modules. Both of these modules contain 30 cases per year, distributed by digital microscopy. In Australia glass slides are routinely used for day to day reporting of patient cases, however for use in an External Quality Assurance Program digital microscopy is now considered to be acceptable worldwide.

The advantages for EQA are that;

• it ensures each laboratory receives an identical image,
• each diagnostic feature is capable of being referenced by its X, Y coordinates in the image,
• variability of staining between slides can be eliminated although viewing conditions can be adjusted to suit participants tastes and, of particular relevance,
• Allows performance assessment for all tissue types including small biopsies.
• This eliminates a major element of imprecision in the process.

The Anatomical Pathology QAP has used digital microscopy for 6 years, initially in pilot studies in 2006 – 2007 and then phased into the surveys from 2007 onwards.

A novel non‐parametric scoring system for measuring participants’ performance for each survey case was developed in 2005 and presented to participants in early 2006. Individual case scores could be aggregated across all cases in a survey or all cases during a longer period such as a calendar year. It has been used since then with only a few minor changes and the system used for this project is a development of this scoring system.