American Journal of Agricultural and Biological Sciences

Variables Refinery Process to Ensure Research Unbiasedness (Validity) and Invariance (Reliability) in Agricultural Extension and Education

Iraj Malek Mohammadi

DOI : 10.3844/ajabssp.2008.342.347

American Journal of Agricultural and Biological Sciences

Volume 3, Issue 1

Pages 342-347


Involving many variables, usually uncertain discrete, lowers the level of consistency and certainty in complex human studies like agricultural extension education. This research, as a part of a study entitled: Side by side situational analysis of current versus future situations of agricultural sector in manifesting the Ninth Malaysia Plan, is dealing primarily with the purpose and process of refining a set of uncertain independent variables to higher research validity and reliability. This investigation is quantitative in its nature, Applied in kind and design-wise, it is an Ex-Post-Facto analytical survey research. Eleven personal and professional characteristics of 224 agricultural experts were taken as independent and 158 attitudinal variables, measured based on dual (side-by-side) Likert scale, as dependent variables. Research population consisted of all agricultural experts including extension experts in Malaysia. As a result, 13 items (8.2% of the attitudinal questions) out of 157 were distinguished as impacted, moderate to very high sensitive variables to few personal characteristics and were eliminated in further data analysis. Applying this variable refinery method considerably increased construct and content validity as well as reliability of the research instrument and helped researcher to construct a rather impact-free side-by-side questionnaire.


© 2008 Iraj Malek Mohammadi. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.