Classification of Early Onset Scoliosis (C-EOS) Has Almost Perfect Inter and Intra Observer Reliability

• Micaela Cyr, BA• Tricia St. Hilaire, MPH• Zhaoxing Pan, PhD• George H. Thompson, MD• Children’s Spine Study Group• Growing Spine Study Group• Sumeet Garg, MD

Sumeet.garg@childrenscolorado.org

Classification of Early Onset Scoliosis (C-EOS)

Williams, B.A., et al., Development and Initial Validation of the Classification of Early-Onset Scoliosis (C-EOS). The Journal of Bone & Joint Surgery, 2014. 96(16): p. 1359-1367

Purpose

• To evaluate the inter-observer and intra-observer reliability of the Classification of Early Onset Scoliosis (C-EOS) scheme

Methods• 50 patient cases drawn from registry

and used to create online survey

• Survey sent to faculty, research coordinators, fellows involved with CSSG and GSSG

• Surveys sent twice to test intra-observer reliability

Methods

Kappa value

Degree of agreement

<=0 Poor

0-0.2 Slight

0.2 - 0.4 Fair

0.4 - 0.6 Moderate

0.6 - 0.8 Substantial

0.8 - 1 Almost perfect

• Fleiss Kappa and Cohen’s Kappa used to asses inter-observer and intra-observer reliability respectively

• Hypothesis: All categories would have Kappa value 0.75 or higher

Results• 36 total participants, 29

completed twice

• Overall Fleiss Kappa for inter-observer reliability was almost perfect for etiology (0.84), Cobb angle (0.93), kyphosis angle (0.96)

Inter-observer reliability

Etiology Cobb Angle Kyphosis Angle0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

10.9 0.91

0.96

0.78

0.95 0.96

Faculty Research Coordinators

Fleis

s K

appa V

alu

e

Intra-observer reliability

• Overall Cohen’s Kappa for intra-observer reliability was almost perfect for etiology (0.92), Cobb angle (0.96), kyphosis angle (0.98)

• Intra-observer reliability was almost perfect across all major categories for all groups

Conclusions• Etiology most difficult to classify, still

demonstrates high reliability

• High reliability with minimal training, varying degrees of familiarity with the system

• C-EOS can be used as a reliable tool

References• 1. Lenke, L.G., et al., Adolescent idiopathic scoliosis a new classification to

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• 4. Williams, B.A., et al., Development and Initial Validation of the Classification of Early-Onset Scoliosis (C-EOS). The Journal of Bone & Joint Surgery, 2014. 96(16): p. 1359-1367.

• 5. Park, H.Y. The Classification for Early Onset Scoliosis (C-EOS) Predicts Timing of VEPTR Anchor Failure. in 2013 AAP National Conference and Exhibition. 2013. American Academy of Pediatrics.

• 6. Cummings, R.J., et al., Interobserver Reliability and Intraobserver Reproducibility of the System of King et al. for the Classification of Adolescent Idiopathic Scoliosis*. The Journal of Bone & Joint Surgery, 1998. 80(8): p. 1107-11.

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