Objective: To report on the results of the consensus process integrating evidence from preliminary studies to develop the first version of a Comprehensive ICF Core Set and a Brief ICF Core Set for chronic widespread pain.
Methods: A formal decision-making and consensus process integrating evidence gathered from preliminary studies was followed. Preliminary studies included a Delphi exercise, a systematic review and an empirical data collection. After training in the ICF and based on these preliminary studies relevant ICF categories were identified in a formal consensus process by international experts from different backgrounds.
Results: The preliminary studies identified a set of 365 ICF categories at the second, third and fourth ICF levels with 143 categories on body functions, 45 on body structures, 125 on activities and participation and 125 on environmental factors. Thirty experts attended the consensus conference on chronic widespread pain (16 physicians with at least a specialization in physical and rehabilitation medicine, 4 rheumatologists, 2 psychiatrists, 5 physical therapists, one psychologist, one occupational therapist and 1 social worker). Altogether 65 second-level and 2 third-level categories were included in the Comprehensive ICF Core Set with 23 categories from the component body functions, one from body structures, 27 from activities and participation and 16 from environmental factors. The Brief ICF Core Set included a total of 24 second-level categories and 2 third-level categories with 10 on body functions, 10 on activities and participation and 6 on environmental factors. No body structures were included in the Brief ICF Core Set.
Conclusion: A formal consensus process integrating evidence and expert opinion based on the ICF framework and classification led to the definition of ICF Core Sets for chronic widespread pain. Both the Comprehensive ICF Core Set and the Brief ICF Core Set were defined.