BACKGROUND:Idiopathic toe walking (ITW) is a diagnosis of exclusion for children walking on their toes with no medical cause. This systematic review aimed to identify and evaluate the clinical utility, validity and reliability of the outcome measures and tools used to quantify lower limb changes within studies that included children with ITW. METHODS:The following databases were searched from inception until March 2018: Ovid MEDLINE, EBESCO, Embase, CINAHL Plus, PubMed. Inclusion criteria were studies including children with ITW diagnosis, reporting use of measurement tools or methods describing lower limb characteristics, published in peer-reviewed journals, and in English. The relevant psychometric properties of measurement tools were extracted, and assessed for reported reliability and validity. Included articles were assessed for risk of bias using McMaster quality assessment tool. Results were descriptively synthesized and logistic regression used to determine associations between common assessments. RESULTS:From 3164 retrieved studies, 37 full texts were screened and 27 full texts included. There were 27 different measurement tools described across joint range of motion measurement, gait analysis, electromyography, accelerometer, strength, neurological or radiology assessment. Interventional studies were more likely to report range of motion and gait analysis outcomes, than observational studies. Alvarez classification tool in conjunction with Vicon motion system appeared the contemporary choice for describing ITW gait. There was no significant association between the use of range of motion and gait analysis outcomes and any other outcome tool or assessment in all studies (p > 0.05).There was limited reliability and validity reporting for many outcome measures. SIGNIFICANCE:This review highlighted that a consensus statement should be considered to guide clinicians and researchers in the choice of the most important outcome measures for this population. Having a standard set of measures will enable future treatment trials to collect similar measures thus allowing future systematic reviews to compare results.