Performance indicators based on data from national quality registries
Refining and expanding the national performance measurement system to include a set of core measures for public reporting, is one explicit goal of the Norwegian government. Calculation of many such measures may require access to patient-level data from e.g. administrative files, medical records or quality registries.
We performed a model-based evaluation to give advice on whether valid, reliable and evidence-based quality indicators may be developed with data from existing national quality registries. There are approximately 30 such registries in Norway, mainly covering hospital care and a range of clinical areas. Diabetes was chosen as a model for the evaluation. We designed the evaluation process in accordance with acknowledged international methods, in order to demonstrate how quality indicators can be developed and tested with a scientific approach and in a transparent manner. Process and outcome measures for diabetes, chosen in ongoing collaborative projects in which the Nordic countries participate (OECD, Nordic Council of Ministers, WHO), as well as the ones used for public reporting in Denmark and Sweden, formed the main basis for our model.
The indicators for diabetes currently in use in the evaluated measurement systems seem to be based on broad professional consensus, as expressed in evidence-based international guidelines and a systematic review prepared by the Danish indicator project. Norwegian clinical guidelines also give support to the validity of these indicators. The set of measures varied somewhat between the systems, probably due to variations in data availability, but also because of differences in purpose and scope of the reporting systems. We also found that the Norwegian quality registries for adult and childhood diabetes enter pertinent information necessary for calculation of all selected measures. However, data from these registers can not be further validated with regard to precision and minimum bias, until earliest in 2009, when both registers have been in operation for one year.
Partly due to legal requirements to obtain patients' permission, and voluntary cooperation from health personnel to enter data manually, we judge data quality in the registries to be suboptimal for indicator report retrieval, until the registries can supplemented and quality assured by linkage with hospital administrative files. Even a better option will be the development of a web-based information technology for interactive data entry from electronic medical records; however this technology will probably not be available in the near future.
In the meantime, we propose to base further development of existing and new indicators for diabetes, on an alternative dataset extracted for the period 2003-2007 from hospital administrative files, linked and matched with laboratory data and relevant public registries. This project will also have relevance for problems which have to be addressed if other quality registries are to be evaluated for indicator report retrieval.