The prevalence of diabetes mellitus in industrial countries lies between 5.9% and 8.1% and has been increasing dramatically due to increasing obesity and lack of exercise. Current recommendations for the medical treatment of DM focus primarily on the close measurement and regulation of blood sugar. In addition, symptoms related to diabetic complications should be monitored closely. A published review of health-related quality of life measurements in diabetes mellitus showed the wide variety of generic, diabetes-specific and psychological measures that had been used in patients with diabetes. However, no systematic framework that covers the spectrum of symptoms and problems in functioning of persons with diabetes mellitus had been established at the time.

To tackle this issue, the ICF Research Branch and the World Health Organisation (WHO) with the scientific support of Hannover Medical School (Germany), Rehaklinik Zurzach (Switzerland), Department of Physical Medicine & Rehabilitation at the "PIKPA" Center (Greece), University of Malaya (Malaysia) and Ludwig-Maximilian University (Germany), initiated a project to develop internationally-accepted and evidence-based ICF Core Sets for diabetes mellitus. This project was part of a larger project examining 12 chronic conditions with a high burden of disease.

The preparatory phase included a systematic literature review, a Delphi exercise and an empirical data collection using the ICF checklist:

• The systematic literature review was performed to identify and compare the concepts contained in outcome measures of randomized, controlled clinical trials published from 1993-2003 involving patients with diabetes mellitus.
• The international expert survey (via email) using the Delphi technique was conducted with 25 health professionals, experts on the treatment of persons with diabetes mellitus, to identify the set of domains that best describe the prototypical spectrum of problems in functioning and health in persons with diabetes mellitus from the of health professional perspective.
• The multicentre cross-sectional study using the ICF checklist with a convenient sample of 67 patients undergoing inpatient or outpatient rehabilitation was performed to identify the common problems experienced by persons with diabetes mellitus.

An international ICF consensus conference took place from 30 May - 2 June 2003 at a quiet monastery situated in a pleasant landscape far from any city and distractions. The aim of the conference was to establish the Comprehensive and Brief ICF Core Sets for patients with diabetes mellitus. Fifteen experts (physicians in various sub-specialities, physiotherapists, epidemiologist and social worker) from 9 different countries decided which ICF categories are to be included in the ICF Core Sets for diabetes mellitus following a formal, decision-making and consensus process which integrated the results from the 3 preparatory studies.

99 ICF categories were selected for inclusion in the Comprehensive ICF Core for diabetes mellitus. These categories can be taken into account when conducting a comprehensive, multidisciplinary assessment. Out of the 99 Comprehensive ICF Core Set categories, 33 second-level ICF categories were selected for the Brief ICF Core for diabetes mellitus. The Brief ICF Core Set can be used in assessing patients participating in a clinical study on diabetes mellitus.

A qualitative study using focus groups has been conducted to validate the Comprehensive ICF Core Set for diabetes mellitus.

For more information, feel free to contact the ICF Research Branch (melissa.selb@paranet.ch).

• Comprehensive & Brief ICF Core Sets for diabetes mellitus (download PDF)