Developing risk assessment tools for type 2 diabetes

Download: Success Story Summary, January 2012 (PDF217.5 KB) / Award Entry Form (PDF 205.5KB)

The challenge 

Accurately identifying people who are at an increased risk of developing type 2 diabetes, or impaired glucose regulation (IGR), helps healthcare professionals effectively target screening tests. University Hospitals Leicester, working with Leicester University, decided to find a way to better identify patients at risk of already having or developing IGR or type 2 diabetes. 

The aim 

The aim of the project was to develop two tools for identifying those at risk of type 2 diabetes or IGR. Firstly, a self assessment score for people from a multiethnic population to assess their own risk, developed in partnership with Diabetes UK. Secondly, an automated tool for identifying people at risk using GP practice databases. 

What did they do? 

The self assessment tool was commissioned and funded by Diabetes UK. The development of the GP database tool did not receive any dedicated funding. 

The developers used data from a population screening programme carried out in Leicester to identify significant predictors of IGR/type 2 diabetes. To design the self assessment tool they only included factors that would be known by the person answering the questions. For the automated tool the variables considered for inclusion were limited to those being routinely collected and stored within GP practice databases. Variables for inclusion in each tool were chosen using a stepwise selection procedure. Once the final set of variables had been selected for each tool the predictive ability of the tools was assessed using data from a second screening study. For each level of the tool the number of people being correctly identified as having IGR or type 2 diabetes was calculated. This enabled thresholds to be set to define a “high risk” person requiring further tests. 

During this process focus groups were carried out to inform the design of the self assessment tool and how the information on risk should be displayed. 

What happened? 

Both the self assessment tool and the automated tool are now being used to identify high risk individuals. The self assessment tool is available on the Diabetes UK web site (www.diabetes.org.uk/riskscore) and has been completed by over 91,000 people. Diabetes UK held road shows in 2010 where the tool was available. They found that 53% of visitors were at moderate or high risk of having or developing Type 2 diabetes in the next 10 years. Of those who were in the higher risk categories, 46% have been to their GP and 27% intend to go. 

In Leicester the automated tool is being used to identify people for inclusion in two prevention programmes. One used the tool to identify the top 10% of people at risk of IGR/type 2 diabetes from GP practices and invited them for screening. From those screened 2,566 received a diagnostic test. 114 (4.4%) were diagnosed with type 2 diabetes and 660 (25.7%) with IGR. The second programme has screened 830 people and of these 29.5% have either IGR or type 2 diabetes.

Key outcomes

• Self assessment tool has been completed by over 91,000 people and is in use by PCTs
  
• Automated GP tool has a positive predictive value for any abnormal glucose tolerance of 30.2%
  
• Self assessment tool received global academic recognition and automated tool is hosted on RCGP website