Delaney-Black V, Covington C, Templin T, Kershaw T, Nordstrom-Klee B, Ager J, Clark N, Surendran A, Martier S, Sokol R J
Department of Pediatrics, School of Medicine, Wayne State University, Detroit, Michigan, USA.
J Commun Disord. 2000 Nov-Dec;33(6):463-80; quiz 480-1. doi: 10.1016/s0021-9924(00)00033-2.
It was hypothesized that prenatal exposure to cocaine and other substances would be related to delayed expressive language development. Speech and language data were available for 458 6-year olds (204 were exposed to cocaine). No significant univariate or multivariate differences by cocaine exposure group were observed. Classification and regression tree modeling was then used to identify language variable composites predictive of cocaine exposure status. Meaningful cut points for two language measures were identified and validated. Children with a type token ratio of less than 0.42 and with fewer than 97 word types were classified into a low language group. Low language children (n = 57) were more likely to be cocaine exposed (63.1%), with cocaine-exposed children 2.4 times more likely to be in the low language group compared with control children after adjustment for covariates. Prenatal cigarette, but not alcohol exposure, was also significantly related to expressive language delays.
研究假设，产前接触可卡因和其他物质会导致表达性语言发育延迟。共有458名6岁儿童的言语和语言数据可供分析（其中204名儿童产前接触过可卡因）。未观察到可卡因接触组在单变量或多变量方面存在显著差异。随后使用分类与回归树模型来识别可预测可卡因接触状况的语言变量组合。确定并验证了两种语言测量方法的有意义切点。词类-词频比低于0.42且词类少于97个的儿童被归为低语言能力组。低语言能力儿童（n = 57）更有可能接触过可卡因（63.1%），在对协变量进行调整后，与对照组儿童相比，接触过可卡因的儿童处于低语言能力组的可能性高2.4倍。产前吸烟而非饮酒也与表达性语言延迟显著相关。
