Negative or positive left or right? The influence of attribute label position on IAT effects in picture-word IATs and word IATs

The Implicit Association Test (IAT) is a widely used measure of implicit attitudes. Despite its application in various fields, the malleability of the IAT by different methodological factors has been shown frequently. In this article, we focus on two factors that potentially influence the IAT effect, but which have received either inconsistent or no support so far: the IAT version (i.e., picture-word IAT vs. word IAT) and the position of the attribute labels on the screen (i.e., the positive or negative label on the left side). In two experiments, we used the original flower-insect IAT to systematically analyse the effects of the position of attribute labels (i.e., the assignment of the positive or the negative attribute label to the left screen position) and the block order of compatible (e.g., flower and positive) and incompatible blocks (e.g., flower and negative) as between-subjects factors. Reliable IAT effects were observed for the picture-word IAT and the word IAT when calculating the IAT effect as a difference in the response times as well as when computing the recommended <i>D</i> Score as IAT outcome. Smaller IAT effects occurred in the picture-word IAT than in the word IAT, supporting existing literature. In addition, an effect of the position of the attribute labels on the screen was found in both experiments, resulting in larger IAT effects when the negative attribute label was positioned on the left. This effect also appeared when calculating the <i>D</i> Score. The study highlights the importance of methodical factors for the IAT outcome.