学习技能诊断测验的诊断敏感性和特异性

Sensitivity and specificity of academic skill diagnostic test

目的验证学习技能诊断测验对学习障碍的诊断敏感性和特异性。方法用华文认知能力量表和学习技能诊断测验测试156名小学生，其中正常学习儿童82名，学习障碍儿童74名。结果在标准分比较模式中，当划界分为低于常模均数1个标准差时，测验的诊断敏感性和特异性最佳，语文分量表对学习障碍的敏感性和特异性为82．4％和90．2％，对语文学习障碍为97．1％和90．2％，数学分量表对学习障碍的敏感性和特异性为75．7％和90．2％，对数学学习障碍为85．7％和90．2％；语文分量表ROC曲线的最佳划界分为86．5、曲线下面积为95．0％，数学分量表ROC曲线的最佳划界分为87．5、曲线下面积为90．2％。在智力-成就分离模式中，当分离分为1个标准差时，测验的诊断敏感性和特异性最佳，语文分量表对学习障碍的敏感性和特异性为63．5％和80．5％，对语文学习障碍为94．3％和80．5％，数学分量表对学习障碍的敏感性和特异性为64．9％和75．6％，对数学学习障碍为92．3％和75．6％；语文分量表ROC曲线的最佳划界分为14、曲线下面积为77．3％，数学分量表ROC曲线的最佳划界分为15、曲线下面积为70．8％。结论学习技能诊断测验具有高的敏感性和特异性，是一套比较理想学习障碍诊断测验。

Objective To test sensitivity and specificity of academic skill diagnostic test （ASDT） in diagnosis of learning disabilities. Method One hundred and fifty-six elementary students （ 82 normal children, 74 learning disabled children） were administered Chinese Cognitive Ability Scale and Academic Skill diagnostic test. Results In the standard score comparison model, when cutoff score was one standard deviation below mean score on the ASDT,sensitivity and specificity of the ASDT was most optimal, Chinese subscale was 82.4% and 90.2% for learning disabilities, and 97.1% and 90.2% for Chinese learning disability, Mathematical subscale was 75.7 % and 90.2% for learning disabilities ,and 85.7% and 90.2% for mathematical learning disability; ROC Curve obtained a optimal cutoff score of 86.5,and area of 95.0% for Chinese subscale, a optimal cutoff score of 87.5,and area of 90.2% for Mathematical subscale. In the IQ-achievement discrepancy model, when discrepancy was one standard deviation,sensitivity and specificity of the ASDT was optimal, Chinese subscale was 63.5% and 80.5% for learning disabilities, and 94.3 % and 80.5 % for Chinese learning disability, Mathematical subseale was 64.9% and 75.6% for learning disabilities ,and 92.3% and 75.6% for mathematical learning disability; ROC Curve obtained a optimal cutoff score of 14 and area of 77.3% for Chinese subscale, a optimal cutoff score of 15 and area of 70.8% for Mathematical subscale. Conclusion The ASDT was an ideal diagnostic test for learning disabilities with high sensitivity and specificity.