Systematic Review
This systematic review aimed to identify predictors of brace treatment outcomes for adolescents or adults with idiopathic scoliosis./r/nFour databases including MEDLINE, EMBASE, Web of Science, and CINAHL were searched. Free text and indexed terms identifying the populations, predictions analyses and key outcomes were combined to search the literature. Pairs from eight independent reviewers conducted abstracts and full-text screening, and data extraction. The Quality in Prognostic Studies (QUIPS) tool was used to assess the risk of bias (ROB). Strength of evidence summary statements were formulated based on the risk of bias and the consistency of the research findings./r/nThe search found 2224 articles. After screening, seven articles were included. Only one article showed low ROB, while the others showed moderate ROB. All articles reported on patient-related outcome measurements (PROMS) of quality of life (QOL). Only one parameter achieved limited strength of evidence; shorter treatment time from one study predicted better long-term SRS-22 total scores. For other predictors, the level of evidence was unclear. Other predictors of long-term outcomes (> 1 year follow-up), from only 1 study on each outcome, were: larger Cobb angle predicted worse Spinal Appearance Questionnaire (SAQ) chest scores and worse depression; higher age predicted better SAQ curve scores, larger apical translations predicted worse SAQ shoulders and chest scores; a passive introverted personality or an active outgoing (MPI) character type predicted worse SRS-22 satisfaction; higher BMI predicted better SAQ curve, Rolland-Morris questionnaire (RMQ) lumbosacral pain, Quebec Back Pain Disability Scale (QDS) moving scores, and worse SRS-22 total; larger vital capacity predicted better QDS score; longer bracing (total) predicted worse depression; negative parental attitudes predicted worse depression; higher Strengths and Difficulties Questionnaire emotional symptoms, peer problems, prosocial behavior, and total scores predicted worse depression. Poor compliance from one short-term follow-up study predicted worse change of brace questionnaire (BRQ) for health perception, pain, physical and emotional functioning, and total scores. Moderate evidence from two studies with low and moderate RoB showed that age and Cobb angle did not predict long-term total SRS-22 score for prediction./r/nEleven parameters predicted bracing outcomes, but most studies presented moderate risk of bias. Only one parameter, longer treatment time, with limited strength of evidence was predictive of better long-term SRS-22 total scores. Since most findings still present an unclear level of evidence, common weaknesses were identified to encourage design of high-quality studies predicting bracing outcomes.