It is time to clamp down on the use of misleading rainbow colour scales that are increasingly pervading the literature and the media (see http://tiny.cc/endoftherainbow). Accurate graphics are key to clear communication of scientific results to other researchers and the public — an issue that is becoming ever more important.
Aside from the challenge they pose for colour-blind readers (340; 2014), spectral-type colour palettes can introduce false perceptual thresholds in the data (or hide genuine ones); they may also mask fine detail in the data ( et al. Nature 510, 14–17; 2007). These palettes have no unique perceptual ordering, so they can de-emphasize data extremes by placing the most prominent colour near the middle of the scale. and Comput. Graph. Appl. 27,
These issues can have profound consequences: for example, changing to a non-rainbow colour scale improved diagnostic accuracy for heart disease (2479–2488; 2011). et al. IEEE Trans. Vis. Comput. Graph. 17,
Journals should not tolerate poor visual communication, particularly because better alternatives to rainbow scales are readily available (see, for example, go.nature.com/zvouhq and http://colorbrewer2.org). We urge all journals to stipulate in their guidelines that graphics must convey accurate and accessible information.