LARGE-SCALE CLASSIFICATION AND QUANTITATIVE GENETIC STUDIES OF READING

项目三需要审查佛罗里达的进展监测和报告网络（PMRN） 数据库包含对300，000名参加的儿童的多种阅读结构的多种测量 在佛罗里达州表现不佳的学校。每年约有124 000名新儿童进入数据库， 在收集数据的六个年级之一：幼儿园到五年级。这 广泛的数据库是唯一配备回答问题有关的六个中心赠款目标。它 将用于估计符合替代分类标准的挣扎读者的百分比， 各种领域的学习障碍（例如，解码受损、理解受损等）。还应当 用于检查学习障碍的替代分类标准（例如，不明原因低压 成就，不充分的增长）是相关的（即，他们是否将同样的儿童归类为学习障碍）。 我们将检验学习障碍的替代分类标准amd的预测有效性 与备选分类有关的环境变量（例如，SES，学校的表现水平， 等等）。以及它们的预测有效性对于定量遗传学研究，我们将确定一个通常较大的 PMRN样本中的同卵和异卵双胞胎数量（N = 9，000），以检查遗传和 环境对阅读结构的影响，它们之间的关系，以及它们在不同时期的成长。 时间我们将使用PMRN中的样本来检查阅读能力与 残疾人以其他方式定义。

Project III entails an examination of the Florida's Progress Monitoring and Reporting Network (PMRN) database containing multiple measures of multiple reading constructs on 300,000 children attending underachieving schools in the state of Florida. Approximately 124,000 new children enter the database each year in one of the six grade levels in which data are collected: kindergarten through Fifth grade. This extensive database is uniquely equipped to answer questions related to each of the six Center grant goals. It will be used to estimate the percentages of struggling readers who fit alternative classification criteria for learning disability in various domains (e.g., impaired decoding, impaired comprehension, etc.). It also will be used to examine how alternative classification criteria for learning disability (e.g., unexplained low achievement, inadequate growth) are related (i.e., do they classify the same children as learning disabled). We will examine the predictive validity of alternative classification criteria for learning disability, amd environmental variables in relation to alternative classifications (e.g., SES, performance level of the school, etc.) and their predictive validity. For the quantitative genetic studies, we will identify an usually large number (N = 9,000) of identical and fraternal twins within the PMRN sample in order to examine genetic and environmental influence on reading constructs, their relationships to each other, and to their growth over time. We will use the sample within the PMRN to examine differential heritability of reading ability vs. disability defined in alternative ways.