Mirror, mirror on the wall: placebo effects that exist only in the eye of the beholder

What the authors concluded

Patients reported robust and statistically significant improvements in seven facial features at the conclusion of the 8-week treatment regimen as well as at 1-month follow-up (for all comparisons, P </= 0.003, median d = 1.14). In sharp contrast, both the treating doctor and blinded, expert raters were unable to detect any improvement whatsoever (for all comparisons, P > 0.05)." Comment: This

Devices that emit this wavelength

Matched on wavelength within 15nm, since LED bins vary by roughly that much and a tighter match would be false precision. Where we have an irradiance figure, the session length is the time needed to reach this study's dose of 0.1 J/cm² at that intensity.

Matching a wavelength is not the same as reproducing a trial. Session times assume the device's published irradiance is accurate at the distance it was measured, which on brand-claim figures is often optimistic. Where a device publishes both a peak and an average we use the average, and where it publishes a falloff curve we use the lowest figure, so these times run long rather than short. Clinical protocols also control for spot size, contact and skin type in ways a home device cannot.