Validation of the German version of the 24-item Early-Onset Scoliosis Questionnaire.

During childhood, early-onset scoliosis (EOS) may show severe progressive deformity, which consequently leads to aggressive treatment strategies, such as serial casting, long-term bracing, or surgical interventions. The latter usually includes repeated surgeries for implant lengthening every 6 months in order to allow sufficient growth of the thorax and spine. In 2011, the 24-item Early-Onset Scoliosis Questionnaire (EOSQ-24) was introduced to measure health-related quality of life for this patient group and their families. Since then, cross-culturally adapted versions of the EOSQ-24 have been published in Spanish, Turkish, traditional Chinese, and Norwegian. The purpose of the study was to transculturally adapt the original English version of the EOSQ-24 into the German language and evaluate the reliability of the German version. After adaptation and forward/backward translation, the German version of the EOSQ-24 was given to the parents or caregivers of 67 EOS patients (33 male, 34 female) Data quality was evaluated by mean, standard deviation, percentage of data missing, and extent of ceiling and floor effects. Reliability was estimated by internal consistency using Cronbach α and item-total correlations. In the study group (n = 67), 12 children were either observed (n = 7) or treated with a brace (n = 5). The other 55 patients were treated surgically with growth-friendly implants. The item response to the German EOSQ-24 was high with a minimum of missing data (1.7%). All items showed very good to excellent internal consistencies (0.879-0.903). Floor effects for the 24 items were between 0% and 31% and ceiling effects between 9% and 78%. The calculated Cronbach α for the 24-item scale was 0.9003, indicating excellent reliability. The German adaptation of the EOSQ-24 shows excellent reliability and therefore is a valid tool to measure objective health-related quality of life in children with EOS.