Burnside G, Pine C M, Williamson P R
WHO Collaborating Centre for Community Oral Health, School of Dental Sciences, University of Liverpool, Liverpool, UK.
Stat Med. 2007 Sep 30;26(22):4139-49. doi: 10.1002/sim.2859.
Clinical studies of dental caries experience generate multiple outcome data for each participant, with information collected for each individual tooth surface. This paper investigates multilevel modelling as a method of analysis for dental caries data, allowing for full use of the data collected at surface level. Data from a clinical trial of a caries preventive agent in adolescents are modelled. The effect of tooth position within the mouth on the development of dental caries is investigated, with the results showing the importance of differentiating between the upper and lower arches, when modelling the probabilities of caries developing on teeth. Calculation of the intracluster correlation using the threshold model is suggested for use in multilevel logistic regression modelling of caries data. This model, which assumes that a dichotomous outcome is based on an underlying continuous variable with a threshold point where the outcome changes from zero to one, is identified to be appropriate for the analysis of caries which is a continuous process, but is only identified as present in a clinical trial when it has reached a certain level of severity.
龋齿经验的临床研究为每个参与者生成多个结果数据，并收集每个个体牙齿表面的信息。本文研究了多级建模作为龋齿数据分析方法，以便充分利用在表面水平收集的数据。对青少年龋齿预防剂临床试验的数据进行建模。研究了口腔内牙齿位置对龋齿发展的影响，结果表明，在对牙齿发生龋齿的概率进行建模时，区分上下牙弓很重要。建议使用阈值模型计算聚类内相关性，用于龋齿数据的多级逻辑回归建模。该模型假设二分结果基于一个潜在的连续变量，该变量有一个阈值点，结果从0变为1，该模型被认为适用于分析作为连续过程的龋齿，但只有在临床试验中达到一定严重程度时才被确定为存在。
