Validation of the comprehensive ICF core set for low back pain: the perspective of physical therapists.

The "Comprehensive ICF Core Set for Low Back Pain (LBP)" is an application of the International Classification of Functioning, Disability and Health (ICF) and represents the typical spectrum of problems in functioning for patients with LBP. The aim of this study was to validate the Comprehensive ICF Core Set for low back pain from the perspective of physical therapists. Physical therapists experienced in LBP treatment were asked about the patients' problems, patients' resources and aspects of environment treated by physical therapists in a three-round survey using the Delphi technique. Responses were linked to the ICF. Eighty-four physical therapists in 32 countries named 1955 concepts that covered all ICF components. Fourteen ICF categories were not represented in the Comprehensive ICF Core Set for LBP although at least 75% of the participants have rated them as important. Most of them belonged to the ICF component "Body Functions". Twenty-eight concepts were linked to the not-yet-developed ICF component personal factors. Further, 21 issues were not covered by the ICF. The validity of the ICF components "Body Structures", "Activities and Participation" and "Environmental Factors" was largely supported by the physical therapists. However, several body functions were identified which are not covered and need further investigation.