The Discrete Choice Experiment
Dr S. Will Beckham works in the field of HIV prevention. I joined Beckham’s seminar where he explained the processes behind his ‘Discrete Choice Experiments’ which involved surveying a group of women involved in prostitution in Tanzania, East Africa (who he mostly referred to as ‘sex workers’).
Beckham gave his presentation in front of his Rainbow and Transgender Flags. Bit sad. Two raw-looking areas of acne around his face and the repeated mentions in his introductory slides and speech of his interest in transgender healthcare suggested that Beckham may in fact be a female testosterone user. (Perhaps people who have dangerous drug habits are perhaps not best placed to undertake studies into drug development.)
The brand name for pre-exposure prophylaxis, commonly known as PrEP, is Truvada. Truvada lists all the known side effects on its webpage, which includes kidney failure, jaundice and bone thinning and is known to be harmful to unborn babies.
I’m really interested in the intersections of reproductive health and HIV and injectable PrEP, implants, patches and rings really echo contraception and have the potential to be multi-purpose technologies where you can combine HIV prevention and pregnancy prevention into one thing. So for women, or for people with uteruses, that’s some great potential down the line.Dr Will Beckham
There are also a number of basic requirements a recipient needs to meet before taking PrEP, including all current medications, past medical history, and regular blood monitoring, so it falls into a complex medical treatment to manage and consent to.
Beckham’s research was aimed at finding out how best PrEP could be established into the community of female workers in Tanzania via their health services, framing it as an empowerment choice. Beckham held ten qualitative in-depth interviews and two focus groups discussions with female sex workers about various formulations of PrEP and how they felt about integrating this into their lives (though it appears they didn’t speak much English, so I don’t see how these could have been in-depth). Their main concerns were naturally side effects and efficacy.
Because the women were illiterate and spoke limited English (or perhaps none, this was not very clear at all), Beckham communicated to them via drawings to elicit what kind of drug delivery they preferred:
- orally showed a woman taking pills,
- intra-muscle via injection showed a syringe near a buttock,
- a vaginal ring was a drawing of a ring being held between a thumb and forefinger, and
- ‘on-demand’ was a pair of drawings where the cartoon woman took pills orally with a man in the bed behind her in different positions.
In order to express their preferences, the women then drew an X on the least preferred method, and a tick on the preferred. (A rectal ring is also apparently a possible product development, not quite sure how you’d get that back).
When explaining the potential side effects of PrEP to the survey participants drawings of a woman waitressing were used:
- No side effects showed the woman at work.
- Mild side effects the woman was still working but had some lines drawn around her head to suggest she was perhaps slowing down/had a headache.
- Moderate side effects showed the woman still in her work clothes but was having to take some headache pills.
- Severe side effects showed her in bed with the covers pulled up. (Since these women ‘work’ in their beds, it’s questionable whether the bedridden state would be recognised as such.)
To say these were inadequate as a tool to explain such complex scenarios would be an understatement. Why couldn’t the project splash some money out on a trained health advocate/translator and explain the full context to them? In Beckham’s acknowledgement slide the HIV healthcare company ViiV was name-checked, which had a turnover in 2019 of almost £5 billion. Hm.
Beckham occasionally referred to women as ‘people with cervixes’ but funnily enough when he talked about a study which surveyed only men, ‘people with penises’ weren’t mentioned once. Can’t think why.
A trial of PrEP as an injectable has just completed, which will only require administration once every two months and has apparently shown superiority to the oral pill, which will likely be rolled out in the next few years.
The women that Beckham spoke to were very unkeen on applying anything vaginally. The women naturally wanted to know more details about side effects. Because Beckham felt that they could only cope with about 16 questions, the choice experiment was broken down so there were less questions about side effects. Beckham also revealed that the women ‘just wanted to give me the right answer’. (One suspects they just wanted to pick up their free condoms, or whatever was on offer at the drop-in centre, and go). Beckham told the women to answer the scenario questions as if they believed the medication was effective.
When researching preferences for PrEP use with English-speaking gay men, the Discrete Choice Experiments were obviously more complex but it appeared to me that the options for responses were limited in that the could chose only one of three scenarios, rather than answering specifically what they wanted, if I understood correctly. For example, one option was low side effects and high stigma versus the option of high side effects and low stigma. The results showed that most had concern about severe side effects, which is news to no one.
The next step on that piece of work was to drill down into the data, to do further race and class analysis, to potentially find those men who cared less about the side effects and identify potential barriers to maximise uptake once injectable PrEP is approved. Hurrah!
The next Discrete Choice Experiment Beckham had designed included a new parameter, explaining the level of protection injectable PrEP may offer to the sexual partners of the user, from 999/1,000 for once monthly, 950/1,000 for twice monthly, to 900/1,000 for three monthly. I assume these options were based on real clinical research data, in which case why would anyone want to increase the danger of transmission by such a significant margin?
The justification for the development of injectable PrEP is apparently stigma. Apparently being seen taking the tablets put men and women off wanting to use oral PrEP. Beckham claimed that Thai men he had spoken to and the Tanzania women had expressed fear that they might be beaten up if they were seen using oral PrEP or that they might be ‘outed’. A non-oral option would make it easier to hide (except the visit to the clinic and the resultant injection marks and rashes presumably).
Educating men about changing sexual behaviours, lifting women out of prostitution, or even the continued role of condoms weren’t mentioned once. Why bother doing that when you can just throw drugs at poor people in countries with inadequate healthcare.
It’s all massaging. I can imagine this research is going to be quoted in a report which will end up on the desks of government officials and various NGOs, with its recommendations that this is a good thing and that Tanzania women are already very excited about the prospect kidney failure and bone thinning. That’s big pharma for you. Always on the money.