While numerical bipolar rating scales may evoke positivity bias, little is known about the corresponding bias in verbal bipolar rating scales. The choice of verbalization of the middle category may lead to response bias, particularly if it is not in line with the scale polarity. Unipolar and bipolar seven-category rating scales in which the…

In randomized experiments, inventories with reverse-keyed items are compared with inventories in which all the items are either positively or negatively associated with the underlying concept. The results show that with reverse keying, a control of the potential bias was not sufficient; likewise, the factorial structure, reliability, and validity…