Adaption of the Skin Sun Sensitivity Scale

1. BACKGROUND AND RATIONALE:

We extended the pilot study (IRB STU27549) of our objective measurement of skin
pigmentation with correlation to the self-reported skin reaction to sun exposure to a
larger sample with special emphasis on people with skin of color and compare the
results to those obtained by spectrophotometry. We found that forty-two percent (114 of
270) of the participants' responses to the burning and tanning questions could not be
classified using standard Fitzpatrick skin phototype (FST) definitions. At present, we
seek to determine the accuracy of an adapted Skin Sun Sensitivity Scale for individuals
of all pigmentation varieties (FST I through VI) as compared with spectrophotometric
measurements assessing FST.

Fitzpatrick Skin Phototyping Skin phototyping has usually been determined subjectively
by trained investigators or clinicians using sun burning and/or sun tanning responses.
In addition, subject self-report of ease of sunburning and tanning is used in surveys
to determine the risk of developing skin cancer. (Table 1) Responses to the Fitzpatrick
Skin Phototype (SPT) questions may be unreliable due to recall bias, subjective bias by
clinicians and subjects, lack of cultural sensitivity of the questions, and the
subjects' use of sun protection behaviors from early childhood such that the subject
may not have experienced sunburn.

Table 1. Skin type; Erythema and Tanning Reactions to the First Summer Exposure I
Always burns, never tan (painful burn at 24 hrs and no tan at 7d) II Burn easy, then
develop light tan (painful burn at 24 hrs and a light tan at 7d) III Burn moderately,
then develop light tan (slightly tender burn at 24 hrs, moderate tan at 7d) IV Burn
minimally-rarely, then develop moderate tan (no burn at 24 hrs and a good tan at 7d) V
Never burns, always develops dark tan VI Never burns, no noticeable change in
appearance

Unreliable Sunburning History A limitation of the 6 integer Roman numeral Fitzpatrick
SPT was reliance upon a history of sunburn after the first exposure of the summer. For
those who reside in regions that have sun exposure all year (e.g. Arizona, Florida,
California), the sunburning-tanning question after the first exposure of the summer was
often irrelevant. Lastly, in the 1990s people began to use sunscreens to prevent
sunburns, thus, those with sun sensitive skin may never have experienced sunburn and
were unable to answer the question about ease of sun burning.

Multi-ethnic Populations There has been a tendency to group all people of a similar
ethnic group into a single category of SPT, which introduces potential bias into the
subjective assessment of SPT by investigators. For example, Hispanic whites are often
considered "brown" and assigned to Skin Type IV (Table 2). The heterogeneity of those
with multi-ethnic backgrounds makes it difficult to assess susceptibility to skin
cancer on the basis of skin color, which is predominantly determined by pigments such
as hemoglobin, melanin, bilirubin, and carotene.

Skin Phototyping by Sunburning Ability. Skin Phototype Appearance Sunburning ability I
Very white or freckled Always burn II White Usually burn III White to Olive Sometimes
burn IV Brown Rarely burn V Dark brown Very rarely burn VI Black Never burn

Over the last 3 decades, the Fitzpatrick SPT evolved from its original purpose of
determining the amount of ultraviolet light (UVL) for treatment of psoriasis patients
living in New England to become an assessment tool for skin cancer risk. As part of
this evolution, the original 4 skin types (I-IV), that assessed sun reactivity with
standardized questions about the ease of sun burning and tanning reactions to the first
summer sun exposure, were modified by adding SPT V and VI to include those with brown
and black skin.

Our research demonstrated that the SPT modifications to include people with skin of
color were neither culturally sensitive nor accurate as people of color were unable to
respond to the questions about their experience with sunburn and tanning. People with
skin of color did not report becoming red or pink but rather experienced "irritation"
after sun exposure. In our recently reported work, we proposed a modification of the
FST questions to allow people with skin of color to be able to respond (Survey
questions 1and 2). We now wish to test the responses of people to these self-report
questions and compare the responses with the melanin index as determined by
spectrophotometry.(Survey question 9)

Spectrophotometry The "gold standard" method of assessing skin pigmentation is
reflectance spectrophotometry (RS). Pershing et al performed seminal research comparing
the area under the curve obtained by RS to profile the constitutive skin color with
clinicians' assessment of SPT. For skin types I-III, Pershing et al (2008) found
inconsistency between clinicians' and reflectance spectrophotometric (RS) assessments
of SPT. The clinicians adjusted the patients' SPT as determined by their historical sun
burning and tanning response by factoring in observed hair and eye color. For example,
red-haired individuals determined by RS to be SPT III were listed as SPT I by clinical
dermatologists. Subjective assessment of SPT by clinicians was heavily influenced by
patients' hair and eye color. The Pershing study, which accrued 125 subjects did not
accrue sufficient numbers of subjects with skin of color (Skin types III-VI) to be able
to report meaningful results. (I 20; II 53, III 21, IV 10, V 16, VI 5)

It should be noted that the area under the curve obtained by RS includes the red
reflectance, thus, it is does not solely represent skin pigmentation. Skin pigmentation
or melanin provides photoprotection and can be calculated as melanin index, MI. (see
following section on Melanin Index) Even as early as 1961, the potential for
confounding of the MI obtained by RS by dilatation of superficial blood vessels was
recognized. The device, Mexameter MX 18, internally corrects for the red reflectance in
calculating the melanin index. The melanin index is derived from the multilayered skin
model and Lambert-Beer's law.

Significance:

While those that are at risk to develop skin cancer have less melanin content (skin
type I) than those at low risk (skin type VI), people with skin phototypes in the
mid-range (III and IV) believe that their natural skin tone is protective against
sunburns, thus, they fail to use sun protection. When people with skin type III and IV
are exposed to more intense ultraviolet light in more southern latitudes than Chicago
they are surprised by the sunburn they experience. In our proof of principle research,
people with skin type III and IV, who viewed the image of their skin on the computer
screen, perceived that the "color was grainy" and made the conclusion that the "holes"
in their skin pigment made it possible for them to burn

This study will further objectively measure the MI of people with skin of color. Thus,
it is essential that we accrue a representative sample of people with skin of color
with all ethnic groups represented over the greatest range of skin types for those
self-identifying themselves as members of the group.

2. STUDY OBJECTIVES:

Our principal objective is to correlate the melanin index under usual conditions by
spectrophotometry with the adapted Fitzpatrick SPT as determined by the patients' responses
to the adapted questionnaire.

Inclusion Criteria:

- Are at least 18 years old

- Are fluent in English

- Are able to complete the study procedures including answering questionnaires

- Are willing to have spectrophotometry readings taken of right upper inner arm

Exclusion Criteria:

- Used self-tanning products or tan accelerators on the right upper inner arm in the 4
weeks prior to enrollment