Dear Aron,
It might help to first break this down into the specific questions you need
to answer. Some of these might be:
1. What is the "natural history" of ambiguous genitalia (a prognostic
question)? That is what happens without surgery? (prognostic question)
Qualitative research would be helpful here to discover what outcomes are
relevant to the effected individuals. But then I want a case-series/cohort
to know how frequent the problems are.
2. What is the impact of surgery on those outcomes, and what are its
adverse effects? (treatment question)
Again qualitative research and case-series can be helpful initially. And if
the impact is dramatic ("all-or-none") then that may be enough to clinch
things. *Some* of your outcomes seem to fall into this category, but I
didn't get a sense of the comparison (what would have happened without
surgery - ie Q1).
I'd certainly rank this data above the opinions of experts (unless those
opinions were based on even better data).
Cheers
Paul Glasziou
At 06/07/2005, Aron Sousa wrote:
>I have a question about the very bottom of the evidence hierarchy.
>
>Most of my work as an educator and clinician deals with issues at the top
>of the evidence hierarchy, but of late I have become involved in a
>clinical area with no high level and little low level clinical
>evidence. I am an internist who has begun to care for adult patients who
>were born with ambiguous genitalia (intersex conditions). Most of these
>people underwent (and many children still undergo) surgeries designed to
>"normalize" the appearance of their genitals (we are not talking about
>urinary, sexual, or reproductive function). In terms of the available
>evidence, the intellectual basis of the surgeries (children with abnormal
>genitals become abnormal adults) is based on a fraudulent case study
>(John-Joan), there is no evidence of a need for these surgeries, there are
>a series of poorly done case series of short-term surgical outcomes, and
>there is a whole host of expert opinions and published MGSATs (multiple
>guys sitting around together). When pressed for justification, surgeons
>(and parents) tend to fall back to fears of future schoolyard and
>lockerroom bullying and harassment.
>
>In general I'd say that you have to do the best you can with the evidence
>you have, but here is the thing. The adult patient reports of their
>treatment are horrific and impressive in their volume and
>consistency. Multiple scholars and reporters have looked for patients
>happy with their treatment and not found one -- not one, not even one who
>is happy but not willing to go public. In truth finding such a patient is
>a bit hard to do since a successfully treated patient would have been lied
>to and would not know of their condition. (There are clearly ethical
>problems as well.) Independent patient report does not make most
>hierarchies of evidence but in the Internet era is one of the most
>prevalent data reports we have.
>
>In this situation there are patient opinions on the value of surgery that
>are nearly unanimous but uncontrolled and self selecting vs. experts with
>little intellectual or ethical standing. How can EBM help me deal with
>this? No fair punting and suggesting I get better data.
>
>Aron Sousa, MD
>Dept. Medicine
>Michigan State University
Paul Glasziou
Department of Primary Health Care &
Director, Centre for Evidence-Based Practice, Oxford
ph: 44-1865-227055 www.cebm.net
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