Peoples Shelagh M, O'Dwyer Laura M, Shields Katherine A, Wang Yang
Boston College, Chestnut Hill, MA, USA.
J Appl Meas. 2013;14(1):57-78.
This research describes the development process, psychometric analyses and part validation study of a theoretically-grounded Rasch-based instrument, the Nature of Science Instrument-Elementary (NOSI-E). The NOSI-E was designed to measure elementary students' understanding of the Nature of Science (NOS). Evidence is provided for three of the six validity aspects (content, substantive and generalizability) needed to support the construct validity of the NOSI-E. A future article will examine the structural and external validity aspects. Rasch modeling proved especially productive in scale improvement efforts. The instrument, designed for large-scale assessment use, is conceptualized using five construct domains. Data from 741 elementary students were used to pilot the Rasch scale, with continuous improvements made over three successive administrations. The psychometric properties of the NOSI-E instrument are consistent with the basic assumptions of Rasch measurement, namely that the items are well-fitting and invariant. Items from each of the five domains (Empirical, Theory-Laden, Certainty, Inventive, and Socially and Culturally Embedded) are spread along the scale's continuum and appear to overlap well. Most importantly, the scale seems appropriately calibrated and responsive for elementary school-aged children, the target age group. As a result, the NOSI-E should prove beneficial for science education research. As the United States' science education reform efforts move toward students' learning science through engaging in authentic scientific practices (NRC, 2011), it will be important to assess whether this new approach to teaching science is effective. The NOSI-E can be used as one measure of whether this reform effort has an impact.
本研究描述了一种基于拉施模型的、具有理论基础的工具——《科学本质量表-小学版》（NOSI-E）的开发过程、心理测量分析和部分效度研究。NOSI-E旨在测量小学生对科学本质（NOS）的理解。为支持NOSI-E的结构效度所需的六个效度方面（内容、实质和可推广性）中的三个提供了证据。未来的一篇文章将探讨结构效度和外部效度方面。拉施模型在量表改进工作中被证明特别有效。该工具专为大规模评估设计，在概念上使用了五个结构域。来自741名小学生的数据被用于对拉施量表进行试点，并在连续三次施测中不断改进。NOSI-E工具的心理测量特性与拉施测量的基本假设一致，即项目拟合良好且具有不变性。五个领域（实证、理论负载、确定性、创造性以及社会和文化嵌入）中的每个领域的项目都分布在量表的连续体上，并且似乎重叠良好。最重要的是，该量表似乎经过了适当校准，并且对目标年龄组——小学适龄儿童具有响应性。因此，NOSI-E应该对科学教育研究有益。随着美国科学教育改革努力朝着让学生通过参与真实的科学实践来学习科学的方向发展（美国国家研究理事会，2011），评估这种新的科学教学方法是否有效将很重要。NOSI-E可以用作衡量这项改革努力是否有影响的一种指标。
