Application of the new index of orthognathic functional treatment need in four district general hospitals

摘要

Indices provide a method of measuring variables. They are used in many aspects of healthcare and dentistry is no exception. For example, plaque indices in periodontology are used to classify plaque levels and to record progress with plaque control measures. In paediatric dentistry, indices can be used to record the incidence and prevalence of hard tissue disease (decayed, missing and filled teeth index). For an index to be useful, it has to be both valid and reliable.1 Validity implies the index measures what it is designed to measure, while reliability means it should be able to produce the same outcome over different time periods and with different operators. Although validity and reliability are important, for an index to gain widespread acceptance, it must also be easy to use.