Discrimination Validity of the Scoliosis Research Society-22 Patient Questionnaire: Relationship to Idiopathic Scoliosis (IS) Curve Pattern and Curve Size

· (c - Depuy Acromed) University of Kansas Medical Center, Kansas City, Kansas, USA

This study was conducted to determine the validity of the SRS-22 patient questionnaire for the discrimination of scoliosis patients based on curve pattern, curve size, and transverse plane trunk asymmetry.

METHODS: Three study groups were developed. The control group (C) consisted of patients who had been referred for evaluation of suspected scoliosis but who had an angle of trunk inclination of ‹ than 5° or an x-ray with scoliosis of ‹ 10°. The non surgical group (NS) consisted of patients with documented idiopathic scoliosis who were either being evaluated and discharged, observed, or who had been or would be braced. The pre surgical group (S) were those being seen prior to primary idiopathic scoliosis surgery. Patients with co-morbidities were excluded.

Measurements: Angle of trunk inclination (ATI) was determined by physical examination; deformity pattern and Cobb from standing frontal and sagittal plane radiographs. Each patient completed a SRS-22 outcomes questionnaire consisting of four domains: pain, self image, function, and mental health; five questions per domain; score 5 best and 1 lowest.

Case Series: Patients were gathered between October 1999 to February 2001. The C group consisted of 20 patients (16F, 4M) average age 13 years. The NS group included 74 patients (62F, 12M) of average age 14 years and average scoliosis of 30° (10-72). The S group consisted of 27 patients (36F, 7M) of average age 14 years with an average curve size of 60° (42-103).

Statistical Analysis: The effect of curve pattern and study group was analyzed with ANOVA. The relationship between the SRS-22 and curve size was calculated using the Pearson correlation coefficient. Significance was p=0.01.

RESULTS: Three domain scores were significantly related to a study group (C, NS, S); pain (4.6, 4.6, 4.2; p=0.005); self image (4.2; 4.1, 3.3; p ‹ 0.0001); mental health (4.5, 4.4,4.0; p=0.007). Seventy-four patients had a single, 26 a double, and 1 had triple curves. There was no significant difference in SRS domain scores based on pattern. There were significant correlations between curve size (range, 10-103°) and SRS-22 score; pain (r=-0.32, p=0.001); self image (r=-0.47, p ‹ 0.0001); function (r=-0.27, p‹ 0.006). The Pearson coefficient between ATI and SRS-22 scores is 0.45 (p ‹ 0.0001) for self-image.

CONCLUSION: The SRS-22 questionnaire successfully discriminates among persons with no scoliosis, moderate scoliosis and large scoliosis by group and by curve size. It does not discriminate among patients with single, double or triple curves.