Re-evaluation of the New Ecological Paradigm scale using item response theory

This study employed the item response theory (IRT) technique to reevaluate the psychometric properties of the New Ecological Paradigm (NEP) scale using a national-level survey dataset from China. This IRT analysis revealed some previously unreported but important issues with this widely-used environmental attitude measure. It was found that the NEP scale has differential measurement precision across the environmental attitude continuum; a method factor may exist; the negatively worded items have less measurement precision than the positively worded items; some items are redundant with regard to item information and a short version consisting of only positive items perform as well as the current version; and the middle response category provides little value. We also found that the dichotomization of the Likert-type response options may offer a promising way to prevent these issues, which could be a useful guideline for the future application of the current NEP scale.