BACKGROUND & AIMS: :This study examined the validity and reliability of portfolio assessment using Messick's unified framework of construct validity. Theoretical and empirical evidence was sought for six aspects of construct validity. Seven faculty raters evaluated twenty student portfolios using a primary trait analysis scoring rubric. A significant relationship (r = .81-.95; p < .01) between the seven subscales in the scoring rubric demonstrates measurement of a common construct. There was a significant relationship between portfolios and GPA (r = .70; p < .01) and the NBDHE (r = .60; p < .01). The relationship between portfolios and the Central Regional Dental Testing Service (CRDTS) examination was both weak and nonsignificant (r = .19; p > .05). A fully crossed, two-facet generalizability (G) study design was used to examine reliability. ANOVA demonstrated that the greatest source of variance was the scoring rubric itself, accounting for 78 percent of the total variance. The smallest source of variance was the interaction between portfolio and rubric (1.15 percent). Faculty rater variance accounted for only 1.28 percent of total variance. A phi coefficient of .86, analogous to a reliability coefficient in classical test theory, was obtained in the decision study by increasing the subscales to fourteen and decreasing faculty raters to three. In conclusion, the pattern of findings from this study suggests that portfolios can serve as a valid and reliable measure for assessing student competency.

背景与目标： ：本研究使用了梅西克构建效度的统一框架来检验投资组合评估的有效性和可靠性。寻求结构有效性的六个方面的理论和经验证据。七个教师评价者使用评分标准对主要特征进行了评估，评估了二十个学生档案袋。评分标准中七个子量表之间的显着关系（r = .81-.95; p <.01）证明了对常见结构的测量。投资组合与GPA之间（r = .70; p <.01）和NBDHE（r = .60; p <.01）之间存在显着的关系。投资组合与中央区域牙科检查服务（CRDTS）检验之间的关系既弱又无意义（r = .19； p> .05）。使用完全交叉的两面概化（G）研究设计来检查可靠性。方差分析表明，方差的最大来源是评分标准本身，占总方差的78％。差异的最小来源是投资组合和专栏之间的相互作用（1.15％）。教师评估者方差仅占总方差的1.28％。在决策研究中，通过将子量表增加到14，将教职人员减少到3，在决策研究中获得了与经典测试理论中的可靠性系数类似的.86 phi系数。总而言之，这项研究的结果模式表明，档案袋可以作为评估学生能力的有效且可靠的方法。