🧑 Human 🎲 Randomized trial, self-controlled 👥 31 participants ⌛ 4-week treatment / 8-week study · 2004 · Taiwan (Kaohsiung)
Blue light phototherapy in the treatment of acne
Tzung · Photodermatol Photoimmunol Photomed · 2004
The protocol this study used
What the authors concluded
Compared with the non-irradiation side, eight sessions of blue light irradiation were effective in acne treatment (P<0.001)." Comment: According to Fig 1, improvement was approximately 50% on blue light side and 10% on non-irradiated side. It seems acne severity was accessed by the investigator.
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 40 J/cm² at that intensity.
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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.
Source
Dosimetry extracted by Vladimir Heiskanen in Photobiomodulation (PBM) research - a comprehensive database. Citation resolved against PubMed.