Intra- and Inter-Model Variability of Light Detection Using a Commercially Available Light Sensor

The veracity of claims made by researchers and clinicians when reporting the impact lighting on vision other biological mechanisms is, in part, reliant accurate valid measurement devices. We aim to quantify intra- inter-watch variability a commercially available light sensor device which has been widely used photobiological research. Intra- differences were investigated between four Actiwatch Spectrum Pro devices obtain measurements two separate occasions, under three different controlled conditions; Gretag Macbeth Judge II lightbox was produce Simulated Daylight (D65), Illuminant A (A) Cool White Fluorescent (CWF) lighting. Significant noted considering tricolour (red, green, blue) white outputs each illuminants (p < 0.01). significant interaction also found watch Intra-watch for (≤0.05), all but one showed no intra-watch difference ‘sensor output’ D65 illuminant. Use spectral sensitivity is an evolving field. Before drawing causal relationships processes, should acknowledge limitations instruments used, their validation, resultant data. outcomes study indicate caution must be exercised longitudinal data collection mixing watches amongst participants avoided.