Campo-Arias Adalberto, Oviedo Heidi C
Instituto de Investigación del Comportamiento Humano, Bogotá, Colombia.
Rev Salud Publica (Bogota). 2008 Nov-Dec;10(5):831-9. doi: 10.1590/s0124-00642008000500015.
Internal consistency reliability is the degree of correlation between a scale's items. Internal consistency is calculated by Kuder-Richardson's formula 20 for dichotomous choices and Cronbach's alpha for polytomous items. 0.70 to 0.90 internal consistency is acceptable. 5-25 participants are needed for each item when computing the internal consistency of a twenty-item scale. Internal consistency varies according to population and then it is necessary to report it always that scale is used.
内部一致性信度是量表项目之间的相关程度。对于二分法选择，通过库德-理查森公式20计算内部一致性；对于多分类项目，则使用克朗巴赫α系数。内部一致性在0.70至0.90之间是可接受的。计算一个包含20个项目的量表的内部一致性时，每个项目需要5至25名参与者。内部一致性会因总体不同而有所变化，因此在使用量表时始终有必要报告该结果。
