关于量表的信度和效度  

On the Reliability and the Validity of a Scale

作　　者：刘学宗[1] 张建[1] 于书彦[2] 

机构地区：[1]首都医科大学数学教研室 [2]首都医科大学教育改革与发展研究所

出　　处：《首都医科大学学报》2001年第4期314-317,共4页Journal of Capital Medical University

基　　金：21世纪初中国高等教育人才培养体系研究计划支持课题 (C0 31)

摘　　要：使用平行信度测定法、2组顺向问题平行信度测定法、两样本t检验法、典型相关法、因子分析法、克朗巴赫系数α值计算法 ,以及Theta系数和Omega系数计算法 ,论述反向问题对信度的影响及其处理技巧 ;介绍对调查问卷中的问题进行检验的方法 ;研究和比较评价量表信度和效度的各种方法 ;提出 2组顺向问题平行信度测定法。结果显示 ,以“北京地区农村医生培养问卷调查表”为依据 ,给出对问卷中反向问题处理前后的克朗巴赫系数α值的变化 ;使用两样本t检验方法对每个问题的临界比率 (criticalratio)检验后 ,筛选掉 2个问题 ,筛选后的克朗巴赫系数α值(0 .8993 )比筛选前的 (0 .892 9)略高 ;2组顺向问题平行信度测定法比较精确 (r1=0 .83 2 ) ;对问卷调查表的各个模块分别计算了克朗巴赫系数α、Theta系数、Omega系数 ,对总表除计算上述系数外 ,还计算了 2组顺向问题平行信度 ,它们的值分别是 0 .8993、0 .881 3、0 .95 65和 0 .82 3 0 ,所有的信度指标都表明该调查问卷具有非常高的信度 ;为简便计 ,选择表中的 1个模块 (“本科毕业生去留原因” ,包括 1 0个问题 )为例 ,使用因子分析法得到十分清晰的统计结构 ,它们表明该模块中的问题既有看得见摸得着的实际问题 ,也有认识上和看法上的问题。The object of the reseach was to describe the effect of the negative questions in a scale on the reliability of the scale and the procedure for recoding the negative questions as well as the hypothesis testing method for the questions in a scale, to investigate and to compare the reliability of a scale obtained with different methods, to compute the parallel reliability between two groups of the positive questions in a scale, to analyze the validity of a scale. The method of the parallel reliability, the method of the parallel reliability between two groups of the positive questions, the indpendent t test method, the canonical correlation, the factor analysis, the methods of computing the Cronbach's coefficient α , the Theta coefficient θ and the Omega coefficient Ω were used. ① Based on the surveillance data of 'The Scale of Training the Rural Doctors in Beijing', the comparison of the Cronbach's coefficient α before and after recoding the negative questions was made. ② By using independent t test to test the null hypothesis of the critical ratio of every question respectively, two questions were sieved and the Cronbach's coefficient rose from 0.892 9 to 0.899 3 after sieving. ③ The simple parallel reliability ( r 1=0.602 7) was much less trustworthy than the parallel reliability between two groups of the positive questions( r p=0.832). ④ The following indicates the whole scale, α =0.899 3, θ = 0.881 3, Ω =0.956 5 and r p =0.823 0 which showed the scale had excellent reliability. ⑤ For the convenience of discussion, we used one model of the scale named 'the reasons of the rural doctors to stay in village or to leave from village' to obtain a distinct statistic structure with the factor analysis method, which showed that the questions in the model could be divided into two groups: one for practical questions, the other rational questions. Endpoints: ① It is important to recode the negative questions in the scale, to compute the reliability a

关 键 词：信度 效度 量表 统计结构 调查研究 

分 类 号：N31[自然科学总论]