The performance of 11 fingertip pulse oximeters during hypoxemia in healthy human participants with varied, quantified skin pigment.

BACKGROUND: Fingertip pulse oximeters are widely available, inexpensive, and commonly used to make clinical decisions in many settings. Device performance is largely unregulated and poorly characterised, especially in people with dark skin pigmentation. METHODS: Eleven popular fingertip pulse oximeters were evaluated using the US Food and Drug Administration (FDA) Guidance (2013) and International Organization for Standardization Standards (ISO, 2017) in 34 healthy humans with diverse skin pigmentation utilising a controlled desaturation study with arterial oxygen saturation (SaO 2) plateaus between 70% and 100%. Skin pigmentation was assessed subjectively using a perceived Fitzpatrick Scale (pFP) and objectively using the individual typology angle (ITA) via spectrophotometry at nine anatomical sites. FINDINGS: Five of 11 devices had a root mean square error (ARMS) > 3%, falling outside the acceptable FDA performance range. Nine devices demonstrated worse performance in participants in the darkest skin pigmentation category compared with those in the lightest category. A commonly used subjective skin colour scale frequently miscategorised participants as being darkly pigmented when compared to objective quantification of skin pigment by ITA. INTERPRETATION: Fingertip pulse oximeters have variable performance, frequently not meeting regulatory requirements for clinical use, and occasionally contradicting claims made by manufacturers. Most devices showed a trend toward worse performance in participants with darker skin pigment. Regulatory standards do not adequately account for the impact of skin pigmentation on device performance. We recommend that the pFP and other non-standardised subjective skin colour scales should no longer be used for defining diversity of skin pigmentation. Reliable methods for characterising skin pigmentation to improve diversity and equitable performance of pulse oximeters are needed. FUNDING: This study was conducted as part of the Open Oximetry Project funded by the Gordon and Betty Moore Foundation, Patrick J McGovern Foundation, and Robert Wood Johnson Foundation. The UCSF Hypoxia Research Laboratory receives funding from multiple industry sponsors to test the sponsors' devices for the purposes of product development and regulatory performance testing. Data in this paper do not include sponsor's study devices. All data were collected from devices procured by the Hypoxia Research Laboratory for the purposes of independent research. No company provided any direct funding for this study, participated in study design or analysis, or was involved in analysing data or writing the manuscript. None of the authors own stock or equity interests in any pulse oximeter companies. Dr Ellis Monk's time utilised for data analysis, reviewing and editing was funded by grant number: DP2MH132941.

The Threefold Path to Equity: Approaches for Health and Aging Researchers.

The authors present a model for pursuing equity in research on health and aging, in terms of: (a) community-driven research governance, with reference to examples inside and outside of the United States, (b) a focus on policy change, where policy is defined broadly in terms of all legislative and regulatory change, and (c) equity-focused research practices, at the level of measurement, analysis, and study design. The model is visualized as a "threefold path" that researchers may walk, to achieve changes within our field, and changes in how we interface with other fields, and communities.

Race-shifting in the United States: Latinxs, Skin Tone, and Ethnoracial Alignments.

In the study, we engage the question of racial "fluidity" by examining patterns of ethnoracial identification in adolescence and, importantly, shifts in ethnoracial identification between adolescence and adulthood using two waves of data from a nationally representative, longitudinal study of adolescents who were in Grades 7 to 12 during the 1994 to 1995 school year. Our theoretical framework draws from social identity theory and brings together bodies of research in race and immigration to make a case for the importance of phenotype, ancestry, and sociocultural elements as potential mechanisms for patterns among Latinx youth, as shifts in ethnoracial identification are predominantly a Latinx phenomenon. The bulk of the findings suggest that both phenotype and immigration are important factors for ethnoracial self-identification among Latinx youth, as well as shifts in their ethnoracial identification in young adulthood. Given what we know about ethnoracial categorization and ascription, findings suggest that, overall, shifts in ethnoracial identification among Latinx youth are primarily about bringing their self-identification into alignment with how they think they tend to be (and most likely are) perceived by others, which we suggest represents a Sedimentation of the Color Line. We close by discussing the myriad implications of our findings for the U.S. racial order and the ongoing debate about how to "measure" the Latinx population.

Skin Tone and Perceived Discrimination: Health and Aging Beyond the Binary in NSHAP 2015.

OBJECTIVES: This paper introduces new measures of skin tone (self-reported) and perceived discrimination that are included in the third round of the National Social Life, Health, and Aging Project (NSHAP). We explain the rationale for these new measures, emphasizing, in particular, how they help researchers to conceptualize and measure the significance of race/ethnicity for health and aging beyond binary ethnoracial categories. METHOD: We describe new measures of skin tone and perceived discrimination for use in NSHAP 2015. We provide descriptive statistics on the distribution of skin tone (self-reported) by race/ethnicity. As a proof of concept, we use logistic and ordinary least squares regression analyses to examine the relationship between skin tone, perceived discrimination, and perceived stress among ethnoracial minorities. RESULTS: We find that there is significant variation in skin tone among non-White respondents in NSHAP 2015 (e.g., non-Hispanic Black and Latinx). We also find that skin tone (self-reported) is a significant predictor of the frequency of perceived discrimination and perceived stress among African American, but not Latinx respondents in NSHAP. DISCUSSION: The inclusion of new skin tone and discrimination measures in NSHAP 2015 provides a unique and novel opportunity for researchers to more deeply understand how race/ethnicity is connected to health and aging among ethnoracial minorities. Furthermore, it will enable analyses of how stress and perceived discrimination also affect patterns of health and aging among Whites against the backdrop of steadily increasing socioeconomic inequalities and shifting ethnoracial demographics in the United States.

Colorism and Physical Health: Evidence from a National Survey.

This study uses nationally representative data to extend a steadily growing body of research on the health consequences of skin color by comparatively examining the consequences of perceived ingroup and outgroup skin color discrimination (perceived colorism) for physical health among African Americans. Using a comprehensive set of measures of physical health, I find that perceived ingroup colorism is significantly associated with worse physical health outcomes among African Americans. Notably, the magnitude of ingroup colorism's associations with most of these outcomes rivals or even exceeds that of major lifetime discrimination, everyday discrimination, and perceived outgroup colorism. These findings compellingly suggest the inclusion of perceived colorism measures in future survey data collection efforts.

Are skin color and body mass index associated with social network structure? Findings from a male sex market study.

Objectives: There is a growing burden of HIV and sex-related diseases in South Asia and India. Sociological research illustrates that key axes of social stratification, such as race and ethnicity, affect social network structure which, in turn, impacts sexual health and wellbeing. Research on networks has increasingly begun to examine the ways in which networks drive or harness sexual behaviors, but has largely neglected the influence of culture and cultural markers in this continuum. Furthermore, much of the existing scholarship has been conducted in the U.S. or in Western contexts.Design: As part of an exploratory effort, we examined how skin color and body mass index (BMI) affected networks among 206 men who have with men (MSM) frequenting sex markets in Hyderabad, India. A novel phone-based network generation method of respondent-driven sampling was used for recruitment. In assessing how skin color and BMI drive these structures, we also compared how these factors contribute to networks relative to two more commonly referenced markers of social difference among Indians, caste and religion.Results: Our findings suggest that skin color and BMI contribute significantly more to network structure than do caste and religion.Conclusions: These findings tentatively illuminate the importance of individual-level heterogeneity in bodily attributes, factors which are seldom considered in conventional approaches to researching how social stratification and health inequalities are animated during the formation of networks.

Linked fate and mental health among African Americans.

Linked fate, the feeling that what happens to one's group may indelibly shape one's own life, is variously conceptualized as an aspect of ethnoracial identity, expression of political solidarity, and/or sense of ethnoracial consciousness. In this study, I contend that, within the context of stigmatization, linked fate may also be compellingly conceptualized as an expression of collective threat and vulnerability with potential relevance for the mental health of African Americans, in particular. Nevertheless, existing research on race and mental health has remained silent on this issue, as linked fate has received little scholarly attention from researchers interested in mental health. Building on prior research on ethnoracial identity, stigmatization, and mental health among African Americans, I introduce linked fate as a neglected, yet important phenomenon among stigmatized minorities, which is deeply associated with ethnoracial identification and should also be considered when examining the consequences of ethnoracial identification on the mental health of African Americans. Using nationally-representative data and logistic regression, I find that linked fate not only fails to be health-protective but is significantly associated with poorer mental health among African Americans in the form of increased suffering from major depression, bipolar I, and anxiety disorders.

The Cost of Color: Skin Color, Discrimination, and Health among African-Americans.

In this study, the author uses a nationally representative survey to examine the relationship(s) between skin tone, discrimination, and health among African-Americans. He finds that skin tone is a significant predictor of multiple forms of perceived discrimination (including perceived skin color discrimination from whites and blacks) and, in turn, these forms of perceived discrimination are significant predictors of key health outcomes, such as depression and self-rated mental and physical health. Intraracial health differences related to skin tone (and discrimination) often rival or even exceed disparities between blacks and whites as a whole. The author also finds that self-reported skin tone, conceptualized as a form of embodied social status, is a stronger predictor of perceived discrimination than interviewer-rated skin tone. He discusses the implications of these findings for the study of ethnoracial health disparities and highlights the utility of cognitive and multidimensional approaches to ethnoracial and social inequality.