RESUMO
INTRODUCTION: The reliability of the cervical vertebral maturation (CVM) method has been questioned. The objective of this research was to evaluate the diagnostic reliability of the CVM method to diagnose the mandibular growth spurt using longitudinal records from an alternative database (Iowa Facial Growth Study [IFGS]) using established diagnostic testing methods. METHODS: Cephalometric films from 43 subjects (males = 20, females = 23) with Class I or Class II skeletal pattern from the IFGS were scanned, digitized, and adjusted for magnification. At least 5 consecutive, annual films were digitized. For each subject, mandibular length (Co-Gn) was measured for each film, and the growth increment between films was calculated. The largest growth increment was the growth spurt. For each subject, the film displaying CVM stage 3 was identified by a blinded examiner viewing the films in random order. Interrater and intrarater repeatability for Co-Gn (intraclass correlation) and CVM staging (weighted kappa) were calculated. Diagnostic tests, including sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were carried out. The present data were compared with data previously derived from samples of the University of Michigan, Oregon, and Burlington Growth studies (UMGS, OGS, and BGS, respectively). A multilevel logistic regression analysis was also run with the mandibular growth peak as the response variable. RESULTS: Interrater repeatability for mandibular measurements (intraclass correlation coefficient [ICC] = 0.91) and CVM staging (k = 0.88) were excellent. Intrarater repeatability for mandibular measurements (ICC = 0.98) and CVM staging (kw = 0.55) were excellent to moderate. The UMGS data demonstrated higher sensitivity with comparable specificity. Accuracy was largely similar. Their PPV and NPV had larger ranges. The OGS and BGS data, compared with the IFGS data, showed that our sensitivity and PPVs were higher, that their specificity was higher, and that the NPV and accuracy were very similar. The regression analysis was applied to age groups 10-11 years through 13-14 years. Only chronological age was significant (P = 0.04). CONCLUSIONS: Agreement between CVM stage 3 and the maximum mandibular growth spurt is inconsistent. The diagnostic capability of CVM for the mandibular growth spurt is questionable.
