Age, Race, Ethnicity, and Sex of Participants in Clinical Trials Focused on Chronic Pain
Two pages on PainSci cite Boyd 2024: 1. Chronic Pain and Inequality 2. Who gets studied? The demographics of pain research
PainSci notes on Boyd 2024:
Boyd et al. studied who gets studied in chronic pain trials. Science about science! You might guess that research probably isn’t exactly producing a lot of data about women and racial/ethnic minorities …
The first thing science has to say about this is that science often doesn’t say who it’s studying: many trials don’t report demographic data, even though they are really supposed to. They just don’t even mention it! The researchers don’t know, or they aren’t telling. Boyd et al.’s report card on reporting was disappointing: specifically, in 500 American clinical trials for chronic pain treatments since 2007, only 37% reported whether or not the subject were older adults, 37% reported ethnicity, and 54% reported race.
Happily, sex was reported by 100% of trials … but that doesn’t necessarily mean they studied women! It just means the papers said whether or not they did.
So did they? Who actually got studied? Some of this does fit cynical expectations, but not as badly as I feared, and there are a couple pleasant surprises. For instance, there was “equitable representation of older adults.” That is, the proportion of study subjects who were older matched the proportion of older adults in the population.
And women? Women were actually over represented! Women are 51% of the population, but 68% of study subjects. This is much higher than I would have guessed. But — important caveat — this doesn’t remotely mean that women’s health is what’s being studied (and it’s probably not).
And now for the shocker: racial and ethnic minorities were all somewhat under-represented! Imagine. It’s not as bad as I expected, but it’s not great. The most poorly represented large demographic group? Asians.
And how about queer folks of any kind? Just no reporting at all. And I mean not even the absence of reporting was reported! Just not even on the radar … so effectively zero representation in chronic pain research.
The situation could be completely different in other parts of the world. And, if all the trials had actually told us who they studied, the representation data might change quite a bit — maybe even a lot, but there’s no way to know.
Boyd et al. concluded that both reporting and representation, although improving, continues to be lousy despite efforts to improve the situation, and specifically “Black, Indigenous, and People of Color (BIPOC) remain underrepresented in clinical pain trials.”
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
There are limited data on equitable inclusion in chronic pain trials. We aimed to (1) identify frequency of reporting age, race, ethnicity, and sex in clinical trials targeting chronic pain, and (2) compare sociodemographic representation to the United States (US) population. We examined US-based intervention trials for chronic pain registered on ClinicalTrials.gov initiated between 2007-2021. We (1) assessed the frequency of reporting each demographic variable, (2) compared representation with US population estimates, and (3) explored change in reporting over time. Of 501 clinical trials, frequency of reporting was as follows: 36.9% reported older adults, 54.3% reported race, 37.4% reported ethnicity, and 100% reported sex. Rates of race and ethnicity reporting increased, but older adult age reporting decreased over time (ps<.00001). Compared to 2020 US population estimates, there was equitable representation of older adults, underrepresentation of individuals identifying as American Indian or Alaska Native [0.8% vs 0.6%], Asian [5.6% vs 2.9%], Black or African American [12.6% vs 12.2%], with more than one race [2.9% vs 1.2%], and Hispanic/Latino [16.9% vs 14.1%]. There was overrepresentation of individuals identifying as Native Hawaiian or Pacific Islander [0.2% vs 0.5%] or White [70.4% vs 72.9%], and of females [50.8% vs 68.4%]. Some representation rates varied by chronic pain condition. Reporting of older adult age, race, and ethnicity was low in chronic pain trials in ClinicalTrials.gov, reinforcing the need for adhering to reporting guidelines. Representation varied across trials compared with US population data, particularly among those identifying as Hispanic/Latino and certain minority racial groups.
PERSPECTIVE: Despite initiatives to increase reporting of demographic information, doing so in clinical pain trials is far from ubiquitous. Moreover, efforts to improve diversity in these trials continue to be insufficient. Indeed, Black, Indigenous, and People of Color (BIPOC) remain underrepresented in clinical pain trials.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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