Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark.
Photodermatol Photoimmunol Photomed. 2010 Dec;26(6):280-4. doi: 10.1111/j.1600-0781.2010.00544.x.
Fitzpatrick skin type (FST I-IV) is a subjective expression of ultraviolet (UV) sensitivity based on erythema and tanning reactivity after a single exposure. Pigment protection factor (PPF) is an objective measurement of skin sensitivity in all skin types after a single exposure.
The aim was to compare FST and PPF with clinically determined minimal erythema dose (MED) and minimal melanogenesis dose (MMD) in 84 persons with skin types I-V both after single and multiple exposures (one, four, five, six, or 12) to buttock and back skin.
FST was better correlated to MED than to MMD, and FST correlated better to constitutive than to facultative pigmented areas after multiple exposures rather than to a single exposure. PPF was generally much better correlated to MED and MMD than FST especially after a single exposure and multiple exposures with steady-state pigmentation. Multiple regression analyses showed that MED was the only significant, or most important determinator, of both FST and PPF. The correlation coefficient was highly significant for PPF (r² =82).
PPF is a better predictor of the individual UV sensitivity (linear relation) than FST (only 4 grades) and PPF can substitute FST.
Fitzpatrick 皮肤类型（FST I-IV）是一种基于单次暴露后红斑和晒黑反应的紫外线（UV）敏感性的主观表达。色素保护因子（PPF）是所有皮肤类型单次暴露后皮肤敏感性的客观测量。
本研究旨在比较 84 名皮肤类型 I-V 个体单次和多次（1、4、5、6 或 12 次）暴露于臀部和背部皮肤后的 FST 和 PPF 与临床确定的最小红斑剂量（MED）和最小黑色素生成剂量（MMD）。
FST 与 MED 的相关性优于 MMD，且在多次暴露而非单次暴露后，FST 与固有色素沉着区的相关性优于与可诱导色素沉着区的相关性。PPF 与 MED 和 MMD 的相关性通常明显优于 FST，尤其是在单次暴露和多次暴露达到稳定色素沉着后。多元回归分析表明，MED 是 FST 和 PPF 的唯一显著或最重要的决定因素。PPF 的相关系数非常显著（r²=82）。
PPF 是个体 UV 敏感性（线性关系）的更好预测指标，优于 FST（仅 4 个等级），并且 PPF 可以替代 FST。
