Table 4. Characteristics of studies using curve angle as an outcome in patients with idiopathic scoliosis treated with bracing or observation.

Reference	Pretreatment curve bracing (B)	Pretreatment curve observation (O)	Posttreatment curve (B)	Posttreatment curve (O)	Change*		Treatment effect† or risk difference (95% CI)
					(B)	(O)
Danielsson et al. (2007)6	Cobb angle: 31.8°‡ (26–38°)	Cobb angle: 29.5°‡ (23–39°)	Cobb angle: 26.4°‡ (14–37°)	Cobb angle: 29.9°‡ (10–42°)	−5.4°	+0.4°	−5.0°
Fernandez-Feliberti et al. (1995)7	Cobb angle ≤ 29°: 25/54 (46.3%) Cobb angle ≥30°: 29/54 (53.7%)	Cobb angle ≤ 29°: 27/47 (57.5%) Cobb angle ≥ 30°: 20/47 (42.5%)	Cobb angle ≤ 39°: 38/54 (70.4%) Cobb angle ≥ 40°: 16/54 (29.6%)	Cobb angle ≤ 39°: 28/47 (59.6%) Cobb angle ≥ 40°: 19/47 (40.4%)	NA	NA	Risk difference −10.7% (95% CI: −.08–.29; P = .26§)
Mannherz et al. (1988)10	Cobb angle: 22° (10–40°)	Cobb angle: 11° (10–15°)	Cobb angle: 29° (0–40°)	Cobb angle: 8° (0–25°)	+7.0°	−3.0°	+4.0°
Pham et al.†(2008)11	Cobb angle: 30.5°‡ ± 3.1	Cobb angle: 26.5°‡ ± 2.4	Cobb angle∥: 17.8°‡	Cobb angle∥: 26.5°‡	−12.7 ± 2.3	0°	−12.7°

^*P values for change scores could not be calculated from raw data. NR indicates not reported; NA, not applicable.

^†Treatment effect is difference in change scores. Negative favors bracing; positive favors observation. Confidence intervals (CI) could not be calculated because standard deviations were not reported by the authors. Data between studies could not be pooled for this reason. Risk difference = Bracing - Observation (rates > 40°). A negative number suggest a smaller failure rate for bracing.

^‡The pre-curve and post-curve angles were statistically significant.

^§Risk difference is not statistically significant; however, bracing group included patients with more severe baseline curves. This is not accounted for in the analysis. Part-time bracing group (not included in analysis) had an 11.0° ± 2.7 improvement.

^∥Calculated from change scores.