Are double-blind trials underestimating drug effectiveness?

In a double-blind trial, patients exhibit the placebo (and nocebo) effects because of the expectation they might be on a real drug.

If expectations are so important, could it be that patients being administered the real drug don't react to it fully due to the expectation they might be on the placebo?

Addendum: Steve Waldman (of Interfluidity and Naked Capitalism) posts in the comments:

@llimllib on twitter - Bill Mill - posted a cite (in response to a tweet on this post) that seems like a nice confirmation of your conjecture. Almost perfect.

Wow.

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Small steps towards single-payer

What happens when the insurer market becomes less competitive?

We test whether insurers that experience larger enrollment increases due to Part D negotiate lower drug prices with pharmacies. Overall, we find that 100,000 additional insureds lead to 2.5-percent lower pharmacy prices negotiated by the insurer, and 5-percent reductions in pharmacy profits earned on prescriptions filled by enrollees of that insurer.

The results seem genuine:

Estimated enrollment effects are much larger for drugs with therapeutic substitutes, and virtually zero for branded drugs without therapeutic substitutes.

And there's also this interesting bit:

We also present evidence that most insurer savings are, on the margin, passed on as lower premiums.

The authors also put the results in perspective:

Naturally, the optimal degree of competitiveness faced by manufacturers depends
both on efficient drug pricing, and the provision of sufficient incentives to innovate. Therefore, it is not clear whether policies to increase competition among manufacturers would harm future welfare by more than they enhance current welfare.

It's interesting how discussions on healthcare reform have focussed almost exclusively on the financial costs of health-care, the bulk of which represent transfers from consumers to health providers and big pharma, with very little discussion of deadweight losses beyond overheads, or any serious attempt at quantifying them.

We spend more time discussing how much we spend on health-care than how much we waste. For economic thinkers, this is very out of character.

And another random observation: I may be wrong here, but I feel like the (non-articulated) current concensus in policy discussions is more-or-less that dynamic effects are not important, and that spending has little to do with innovation and improved health outcomes in the future. Going further out on a limb, I think I can trace this change to Robin Hanson's campaign and his popularisation of the RAND study, but of course this is just a gut feeling.

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Striking numbers

[...] women (physicians) spend 20% to 25% less time in practice than men.

These are dangerous statistics to quote without having checked the methodology, but the numbers make sense. You can find some earlier blogging I did on statistical discrimination here.

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The very poor and rich consume the most healthcare

It’s not generally appreciated that health care expenditures for people in the lowest 15% of income are 50% to 100% greater than for people of average income. There’s also a difference at the high end. The wealthiest 15% also consume more, but only about 20% more. So there’s greater utilization at both ends of the income spectrum, but for different reasons and with different outcomes.

More spending at the high end improves outcomes, not simply for a specific condition but across the board, because the care consists of a broader spectrum of beneficial services. More yields more. But among the low-income patients, outcomes are poor despite the added spending. In fact, the added spending is because of poor outcomes – more readmissions, more care for disease that’s out of control.

That's Richard Cooper, and the numbers sound plausible. The interview is interesting throughout.

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Prison and TB

Using longitudinal TB and cross-sectional multidrug-resistant TB data for 26 eastern European and central Asian countries, we examined whether and to what degree increases in incarceration account for differences in population TB and multidrug-resistant TB burdens.

We find that each percentage point increase in incarceration rates relates to an increased TB incidence of 0.34%.

Net increases in incarceration account for a 20.5% increase in TB incidence or nearly three-fifths of the average total increase in TB incidence in the countries studied from 1991 to 2002.

The paper (gated) is here.

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