The Efficacy of the Fitzpatrick Scale in Clinical Practice

Abstract

Description

Many skin diseases can manifest differently depending on the pigment of one’s skin. The Fitzpatrick scale is a classification of phototypes (I–VI) that categorizes patients’ skin based on its ability to tan and burn. Even though it is a simple questionnaire, the Fitzpatrick scale has numerous criticisms due to its dependence on patients’ self-perception, variability in how questions are asked, limited range, and the underestimation of the risk of skin cancers. Alternatives to the Fitzpatrick scale include the melanin index, pigment protection factor, a visual color scale, and using artificial intelligence along with existing or new scales. Having a more accurate and precise tool to measure skin tone is imperative for research, education, and the patient care of individuals with diverse skin tones.

Introduction

The Fitzpatrick scale is a classification of skin phototypes (I–VI) based on self-reported tendencies to sunburn and tan when exposed to ultraviolet (UV) radiation.¹ The Fitzpatrick scale is a widely used method in dermatology to categorize skin types because of its apparent simplicity and ease of use.² The Fitzpatrick scale was developed in 1975 by Thomas Fitzpatrick to calculate an initial dose for psoralen and ultraviolet A (PUVA) therapy for psoriasis in the non-Hispanic White population.^1,3 Depending on the patient’s degree of skin pigmentation, the initial exposure time of long-wave UV light varied.⁴ The minimal erythema dose was calculated to estimate the amount of UV energy required to produce erythema of the skin.⁴ The need for the classification emerged because patients who had dark hair and dark eyes developed unexpected severe phototoxic reactions to their PUVA doses. The solution to calculating the correct PUVA doses for patients became a short personal interview regarding their history of sunburning and tanning to estimate the patient’s tolerance to UV exposure.⁵ Psoralen and ultraviolet A therapy became an effective and favorable therapeutic modality for psoriasis compared to topical corticosteroids, tar preparations, and oral methotrexate due to its ease of administration and minimal toxicity.⁴ In addition, a questionnaire regarding a patient’s history of sunburn and tanning was developed, asking, “How painful is your sunburn after 24 hours?” and “How much tan will you develop in a week?”¹ This led to the development of the Fitzpatrick scale.¹

Originally, 4 groups (skin phototypes I–IV) were identified. Skin phototypes V (dark brown skin) and VI (black skin) were later added but were based on the patient’s skin color rather than their sun reactivity (Figure 1).¹ Since then, the Fitzpatrick scale has been the most widely accepted method of phototyping in dermatology. However, there are criticisms and concerns due to its subjective classification.¹ To illustrate the shortcomings of the Fitzpatrick scale, in this article, we present 2 groups of individuals with a variety of skin tones reporting the same Fitzpatrick scale and a second group with similar skin tones to the first group but with various Fitzpatrick skin types.

Figure 1.

The Fitzpatrick scale provides a classification system for an individual’s skin type based on the ability to burn and/or tan when exposed to ultraviolet light. It is used to approximate the degree of skin pigmentation.

Clinical Examples

Here we present 2 sets of images. Figure 2 represents patients whose self-reported Fitzpatrick scores all correspond with a Fitzpatrick VI (never burns, always tans). The first 9 examples (Figures 2A–2I) list individual descriptions for these Fitzpatrick VI patients. This is in comparison to the patients in Figure 3, who have what appear to be similar skin tones but have different Fitzpatrick skin types. The latter 9 examples correspond to the individual descriptions of the patients in Figure 3. These images aim to demonstrate the common pitfalls in using the Fitzpatrick scale to assess skin tone. Additionally, as was noted by some patients, they were surprised that, as black or African American, they could get a sunburn, as they were previously told that they could not.

Figure 2.

The patients shown all report never getting a sunburn and always getting tan (Fitzpatrick type VI). Each is an example of a person who is Fitzpatrick type VI. They demonstrate the variety of skin tones that report the same Fitzpatrick skin type (A–I).

Figure 3.

The patients shown have a variety of different Fitzpatrick skin types: Fitzpatrick type II (A), type III (B, C, G, H), type IV (E, F, I), and type V (D). Note that these skin tones are similar to those in Figure 2; however, their Fitzpatrick skin types are different.

Figure 2A depicts a 70-year-old Caucasian man who reports that he has never had a sunburn and always tans. He has a lifelong history of chronic sun exposure with minimal sun protection.

Figure 2B depicts a 10-year-old Hispanic girl. She and her mother report that she regularly spends time out in the sun during the summer, but she never gets sunburns.

Figure 2C depicts a 67-year-old Filipino woman who reports that she has never sunburned, always tans, and has a history of prolonged sun exposure without photoprotection.

Figure 2D depicts a 75-year-old Hispanic man who reports that he has never been sunburned, and he always tans. He reports a lifelong history of sun exposure without photoprotection.

Figure 2E depicts a 24-year-old Hispanic man who reports that he only tans and has never sunburned. He worked in fields exposed to the sun for many years without photoprotection.

Figure 2F depicts a young Filipino man who reports no history of sunburns and always tans. He regularly spends time and exercises in the sun.

Figure 2G depicts a young African American woman who reports a history of no sunburns. Her job requires her to be outdoors regularly. She also actively exercises outdoors. She reports that she has never gotten faintly red or burned in her life. She reports that she gets darker during the summer.

Figure 2H depicts a college-aged South Asian woman who reports that she has never had a sunburn and always tans. She regularly spends time outside.

Figure 2I depicts a 44-year-old African American woman who reports that she never burns and always tans.

Figure 3A depicts a 14-year-old Caucasian girl who usually burns and rarely tans. This image represents what we often think of as a Fitzpatrick type I–II skin type.

Figure 3B depicts a 24-year-old Hispanic girl who burns occasionally but often becomes tan.

Figure 3C depicts an 11-year-old African American boy whose mother reports that he spends long periods out in the pool. He will always burn, and then he becomes tan. They reported that they were surprised, as people often think that darker skin types do not burn.

Figure 3D depicts a middle-aged Hispanic woman who reports that when she was younger, she would work in the fields of Mexico, and she would get a little red and then would tan.

Figure 3E depicts a 25-year-old black woman who reports that she rarely burns when she is out in the sun but easily tans.

Figure 3F depicts a middle-aged Nigerian man who reports that he will get sunburns when he is out in the sun. His skin will peel, and then his skin will get darker. This would correspond to a Fitzpatrick type III based on the questionnaire.

Figure 3G depicts a 64-year-old African American man who reports that when he is out in the sun, he gets bad sunburns, and then he peels and gets darker. This would correspond to a Fitzpatrick type II or III.

Figure 3H depicts a 66-year-old African American woman who reports that she always burns and peels after sun exposure. She was always confused about her sunburning because she was told that Black people could not sunburn. This would correspond to a Fitzpatrick type III.

Figure 3I depicts a 60-year-old African American woman who reports that when out in the sun, she burns a little, and then she tans. This would correspond to a Fitzpatrick type IV.

Discussion

Inaccurate Phototyping

As can be observed from the cases presented, there are significant limitations of the Fitzpatrick scale in assessing an individual’s skin tone. This supports previous criticism that the Fitzpatrick scale has limited use in clinical practice.⁶ One criticism is that the scale is based on the patient’s self-perception of their skin’s ability to burn or tan.⁶ For example, some darker skin types are less likely to recognize when their skin has been burnt.⁶ Patients with darker skin types were not included in the original Fitzpatrick scale types I–IV. They were later incorporated as types V and VI using the visual appearance of skin color.² The Fitzpatrick scale describes types V and VI as “always tans, never or rarely burns,” which is an inaccurate description of darker skin types.⁶ Recent studies show that darker skin types can and do sunburn more than previously thought.^1,6 In fact, all skin types are susceptible to some element of burning from UV radiation.⁷ Patients with darker skin types may not be able to accurately determine if their skin has been sunburnt and therefore, categorize themselves into an inappropriate phototype based on their perception.⁶ Furthermore, patients with skin of color often underestimate their skin cancer risk.¹

Variability in how the Fitzpatrick questionnaire is worded by dermatologists can modify the patient’s perception and elicit different responses. The Fitzpatrick questionnaire has been adapted to be used in different settings and relies on human interpretation and recollection. ^8,9 A study showed that in a population with dark pigmentation, patients preferred to answer the questions of burning and tanning separately rather than a single combined answer due to limited response options that aligned with their perception.⁸ Concerns were also raised about whether patients were answering questions based on single or multiple skin exposures, as the Fitzpatrick scale was intended to evaluate a single skin exposure.^8,9 A modified Fitzpatrick classification was created in some areas, such as India, to include the patient’s genetic predisposition.⁸ The modified questionnaire included eye color, hair color, and the color of unexposed skin.⁸ This led to a 16% change in responses in comparison to the original questionnaire, and patients were able to identify their phototype more easily.⁸

The patient’s self-perception of their skin color and their ability to burn or tan can be influenced by the community that they live in.¹ In Europe, the Fitzpatrick scale often categorizes those from Asia, North Africa, South Africa, Central America, and South America to be type V.¹ On the other hand, those same skin types in other geographic regions considered themselves as type III or IV.¹ On the other hand, those same skin types in Asia and North America considered themselves as type III or IV.¹ This shows that people categorize themselves into different Fitzpatrick types depending on what part of the world they live in.¹ Societal perception of skin can also influence patients’ responses. For light-skinned Caucasian individuals, tanned skin is portrayed as more attractive, causing them to overestimate their skin pigmentation, which is known as “the dark shift.”⁹ However, for dark-skinned African women, lighter skin is more attractive, causing them to report at least 1 Fitzpatrick category lighter.⁹ As people migrate and have interracial children, identifying a phototype based on location, race, and ethnicity may become more challenging.¹⁰

Skin Cancer Risk

Another criticism of the Fitzpatrick scale is that it suggests a linear relationship between skin color and skin cancer risk. As was noted by some of the patients in this article, patients with skin of color can sunburn, which increases their risk of skin cancer.¹ Skin cancer is less common in darker skin types but is associated with higher morbidity and mortality due to later diagnosis.¹ The most common skin cancer in darker skin tones is squamous cell carcinoma (SCC).¹ Squamous cell carcinoma and melanoma can both occur in areas of the body that are not exposed to the sun.¹ The Fitzpatrick scale suggests a much lower rate of skin cancer in darker skin types. This may lead to an underestimation of risk in these populations, which can lead to a false sense of security for both physicians and patients.¹

Innovations and Development in Measurement

The Fitzpatrick scale has long served as a valuable tool in dermatological practice.² However, the need for improvement and innovation arises from the inherent limitations of this classification system.² The original scale was designed for a specific population, and its applicability to a diverse and global demographic remains uncertain.² There has also been a modern push to increase inclusiveness and diversity and to overcome many years of systematic racism in medicine.² Moreover, a key component of the scale relies on subjective responses, which introduces potential inaccuracies and bias.² As our understanding of dermatological conditions advances and the need for personalized medical approaches grows, there is a compelling call to enhance the Fitzpatrick scale.

To improve the Fitzpatrick scale, the Fitzpatrick questionnaire can be refined to ask about skin irritation, tenderness, itching, and skin darkening after sun exposure.¹¹ Robinson et al concluded that using the modified questionnaire on Latin Americans resulted in more patients being categorized as Fitzpatrick II instead of a higher Fitzpatrick level, which means that their actual risk for skin cancer was higher than their perceived risk.¹² However, the responses from the modified questionnaire are still subjective.

To objectively categorize patients with a wide range of skin pigmentations, multiple alternative methods have been proposed to address the limitations of the Fitzpatrick scale. A reflectance spectrophotometer can be used to measure the melanin index.^8,11 It can accurately identify skin color in nonwhite patients, and it has a positive correlation with clinician-assessed skin phototypes.⁸ Melanin index and redness are more effective in predicting skin cancer risk.⁹ However, reflectance spectrophotometers only identify skin color and not photosensitivity.⁹ It may also be impractical and cost-prohibitive in the clinical setting due to the usage of specialized devices.^9,11

Diffuse remittance spectroscopy can be used to measure the pigment protection factor (PPF) by provoking a perceptible erythema after a single exposure.⁸ It objectively assesses the patient’s ability to burn by calculating the standard erythema doses required to reach 1 minimal erythema dose.⁸ Minimal erythema dose is used to estimate the skin’s UV sensitivity.⁸ Minimal erythema dose may also objectively assess the patient’s ability to tan by calculating the minimal melanogenesis dose required to produce perceptible pigmentation after 7 days.⁸ Wulf et al found that PPF was more reliable in measuring sun sensitivity in comparison to the patient-reported Fitzpatrick system, especially in patients with darker pigmentation.¹³

A visual color scale can be used to allow patients and dermatologists to choose a color that closely matches their skin tone.^1,8 The Taylor Hyperpigmentation Scale has 10–15 skin hues in a spectrum of skin tones.^7,11 Studies have found a linear correlation between the color bar and melanin index in an ethnically diverse group.^1,8 While the Taylor Hyperpigmentation Scale is a practical tool in the clinical setting, it is not widely available and needs additional skin hues added.¹¹

Artificial intelligence (AI) can be used to assess pigmentary scores without human bias.³ As previously stated, the Fitzpatrick scale was originally created for a specific population. However, the generalizability has not been established.³ Existing scales, such as the Taylor Hyperpigmentation Scale, or new scales can be implemented into an algorithm to designate skin types without the influence of perceived ethnicity using AI.³ This may allow for more personalized clinical recommendations.³ An example of the integration of AI into photo-typing is through the Monk Skin Tone (MST) scale.^14,15 The MST is an open-source 10-tone scale that has been adapted by AI tools, including those from Google and Meta.^14,15 This scale has been shown to have interrater reliability and correlates with photometric measurements in darker skin tones.^14,15 When AI implemented the MST, it was found to outperform other previously developed skin tone scales that were based on the Fitzpatrick scale.^14,15 The MST scale does have limitations, including the inability to assess melanin index and sun sensitivity.¹⁴ Despite these limitations, the MST scale shows promising preliminary results of implementation in dermatology and how phototyping measures may be utilized with AI.¹⁴

Conclusion

In a 2020 New York Times article titled “Dermatology has a problem with skin color,” Rabin discusses how most medical textbooks and resources primarily feature images of skin conditions on white skin, making it challenging for dermatologists to identify certain conditions on darker skin tones accurately.¹⁶ This gap in visual resources can lead to delayed or missed diagnoses for Black and Hispanic patients, underscoring the need for more inclusive representation in dermatology education to improve care quality and diagnostic accuracy for people of all skin tones.¹⁶ Thankfully, there has been a recent push to include a wider range of skin tones in dermatology education, improving the ability of future dermatologists to recognize and diagnose skin conditions accurately across all skin types.¹⁶

We presented 18 patient cases demonstrating the shortcomings of the Fitzpatrick scale. The Fitzpatrick scale, while widely used in clinical practice, faces substantial criticism and limitations. The reliance on subjective self-perception for categorizing skin types, particularly in darker skin tones, introduces inaccuracies.¹ Variability in questionnaire wording, cultural influences, and societal perceptions further complicate the categorization process. These issues pose challenges in assessing skin cancer risk, as the scale suggests a linear relationship between skin color and risk. This potentially leads to an underestimation of skin cancer risk in populations with darker skin pigmentation.¹

In response to these limitations, various innovations and developments have been proposed. Refining the Fitzpatrick questionnaire to include factors like skin irritation and tenderness is suggested, but subjectivity persists. Objective methods such as reflectance spectrophotometry, diffuse remittance spectroscopy, visual color scales, and artificial intelligence offer promising alternatives. These technologies provide more accurate and unbiased assessments of skin characteristics, addressing the limitations of the Fitzpatrick scale. However, practicality, cost, and accessibility remain challenges for some of these methods.

Moving forward, a combination of objective measurement methods, technological advancements, and the integration of artificial intelligence may pave the way for more accurate and personalized skin type assessments. As we strive for a more comprehensive understanding of diverse skin types, these advancements hold the potential to enhance clinical recommendations and improve skin cancer risk assessment, fostering a more inclusive and effective approach to dermatological care.

Funding Statement

This research was supported (in whole or in part) by HCA Healthcare and/or an HCA Healthcare-affiliated entity.