I was certainly eligible and at that point I was intending to go into the trial, and just their inability to give me the most basic information - okay, maybe a research nurse is not, you know, the people running the trial might have known it and they - but you’d have thought you would have trained up the personnel at the frontline in that particular disease having, you know, I wouldn’t expect every nurse to know the kind of information I was asking, but I would have expected a research nurse on that particular trial to know it.
Was your worry more about what that meant for the trial and whether they’d actually done enough literature searching to make sure that this was a sensible intervention to choose? Or was it more about yourself and thinking “Heck, I’ve got high blood sugar. I want to know that I’m getting a sensible intervention”?
It was definitely about myself. It wasn’t thinking, “Well, if they don’t know this then they’re doing the whole trial badly.” It wasn’t that thought. It was very much about my personal relationship with them, and thinking “I, you know, I need this information. Why aren’t they giving me it?” And also, I don’t know whether it was true, but I wondered whether they didn’t want me to know, to know about it, because they didn’t want me, anybody doing anything that might affect the result of the trial. And I thought, “That’s totally unethical.” And besides which, randomisation means there’s just as many irritating people like me that are going to go and do, you know, additional interventions in both arms so it doesn’t matter, you know. That’s the whole great thing about randomisation. You get two groups that are comparable, and yes, people go and do extra things but they do it in both arms so, so what? So I did get that kind of feeling about it, which I think, you know, given that there is something that you can do to prevent onset of diabetes, you know, get your weight down, do exercise, then if that was being withheld from me, rather than pure ignorance on behalf of the research nurse, then that’s totally inappropriate.
I did wonder if that was partly the motivation, that they didn’t want any confounding variables creeping in, and people…….
Yeah, but you see they’re not really confounding variables; it’s just noise that means you need a bigger sample. Just like people filling in the wrong diary on the yoghurt trial - there’s bound to be odd, you know, “I can’t remember”, and misclassification of the stool [laughs], you know, softer or harder than it was, you know? There’s bound to be that. The point is you’ve got enough people for the true result to be coming out despite that.
FOOTNOTE: The number needed for each trial (the ‘sample size’) is proposed by statisticians doing ‘power calculations’. In some cases a small number of participants may be enough, but if you are looking for fairly small changes in outcome you will need large numbers of participants to pick these up reliably.
