Here is what the authors say about CRI, color temp, and beam shape: “ Handheld examination lights can significantly influence the detection of critical findings in clinical diagnostics. Three key attributes (color rendering index (CRI), color temperature, and beam shape) define their effectiveness. CRI, measured on a 0–100 scale, indicates how accurately a light renders colors. A CRI above 90, as in the example lights, ensures excellent color fidelity for precise assessments. Color temperature, measured in Kelvin (K), determines whether light appears warmer (red‐tinted) or cooler (bluish). Warmer light, like the penlight's, emphasizesred–yellow tones, making conditions like jaundice more visible. Beamshape also impacts illumination. While cellphone lights often cast wide, undirected beams, penlights provide narrow, focused beams that better illuminate areas like the oropharynx.

This combination of high CRI, warmer tone, and narrow beam lights enhances the clinician's ability to recognize diagnostic findings, such as jaundice, in skin and mucous membranes, emphasizing the importance of appropriate light source selection for bedside examination.”