Threats to validity when using open-ended items in international achievement studies : Coding responses to the PISA 2012 problem-solving test in Finland
Arffman, I. (2016). Threats to validity when using open-ended items in international achievement studies : Coding responses to the PISA 2012 problem-solving test in Finland. Scandinavian Journal of Educational Research, 60 (6), 609-625. doi:10.1080/00313831.2015.1066429
Published inScandinavian Journal of Educational Research
© 2015 Scandinavian Journal of Educational Research. This is a final draft version of an article whose final and definitive form has been published by Taylor & Francis (Routledge). Published in this repository with the kind permission of the publisher.
Open-ended (OE) items are widely used to gather data on student performance in international achievement studies. However, several factors may threaten validity when using such items. This study examined Finnish coders’ opinions about threats to validity when coding responses to OE items in the PISA 2012 problem-solving test. A total of 6 discussions during 6 coder practice sessions (on 6 OE items) and an interview between 5 coders were audiorecorded and analyzed by means of content analysis, and 3 main threats to validity were found: (1) unclear and complex questions; (2) arbitrary and illogical coding rubrics; and (3) unclear and ambiguous responses. Suggestions are given as to how to respond to these threats in order to improve the validity of international achievement studies.