Hip problems in older adults: Classification by cluster analysis

No validated classification system of hip disorders in primary care is avai lable. This study explores whether it is possible to obtain such a classifi cation with the method of cluster analyses. A total of 224 consecutive pati ents aged 50 years or older, consulting the general practitioner for pain i n the hip region, and referred for X-ray investigation of the hip, underwen t a standardized examination. Ward's cluster analysis with variables from h istory and physical examination of the hip region resulted in a classificat ion with nine different clusters. These clusters were reproduced in 10 rand om subsamples and with an alternative cluster analysis. Significant relatio nships of various external variables (radiological and sonographic signs an d variables of low-back and knee examination) with the distinctive clusters were found. Twenty of the approached experts recognized the symptoms in se ven clusters as identifiable syndromes. However, further validation of the achieved classification system, especially with respect to the clinical imp ortance, is needed before introducing it into clinical practice. (C) 2001 E lsevier Science Inc. All rights reserved.