Interrater Reliability and Diagnostic Accuracy of Pelvic Girdle Pain Classification
Received 7 November 2006; received in revised form 1 January 2007; accepted 9 January 2007.
Abstract
Objective
The purpose of this study was to measure the reliability of a classification system for pelvic girdle pain (PGP) and diagnostic accuracy of selected examination and clinical special findings for diagnosis of PGP.
Methods
The design involved a prospective epidemiological study of pregnancy-related PGP. Consecutive subjects were recruited and classified using criteria defined by previous studies. Two clinicians examined the subjects and classified each patient into 1 of 5 classification groups. Clinical examination and clinical special tests were performed on the patients with PGP. Statistical analysis involved interobserver agreement using a κ statistic and sensitivity and specificity values for the examination and clinical special testing.
Results
Twenty-one subjects were included in the analyses. Aggregated percentage of agreement for the classification system was 84.6%. The Cohen κ was 0.78 (CI, 0.64-0.92; P < .0001), which indicated substantial agreement during selection of the classification system. Most clinical examination and clinical special-test findings demonstrated low sensitivity and high specificity, whereas clusters of findings including the lunge, manual muscle testing of the hip (lower extremities), and passive range of motion of the hip demonstrated the strongest diagnostic value.
Conclusion
Selected tests and measures are moderately discriminatory in diagnosing PGP. A classification system for diagnosing PGP demonstrates strong agreement and may be useful for clinicians.
aAssistant Professor, Department of Community and Family Medicine, Duke University, Durham, NC
bPhysical Therapist, Physical and Occupational Therapy, Duke University, Durham, NC
cGraduate Student, Division of Physical Therapy, Department of Community and Family Medicine, Duke University, Durham, NC
dAssociate Professor, Department of Community and Family Medicine, Duke University, Durham, NC
Submit requests for reprints to: Chad Cook, PT, PhD, MBA, Assistant Professor, DUMC 3907, Duke University, Durham, NC 27278.