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For those interested in D. Nutt's publication please check this link for comments we have published in Significance today: http://www.significancemagazine.org/details/webexclusive/876871/Alcohol-is-more-harmful-than-heroin-part-2--Subjectivity-Overdose-.html Maria Viskaduraki, PhD Biostatistician University of Birmingham -----Original Message----- From: A UK-based worldwide e-mail broadcast system mailing list [mailto:[log in to unmask]] On Behalf Of Jay Warner at AT_T Sent: 06 November 2010 07:01 To: [log in to unmask] Subject: Re: Nutt, King & Phillips, Lancet 2010, 376, 9752, 1558 - 1565 This article has made its way to US news feeds and might continue to receive attention in a wide audience. Therefore, anyone who wishes to discuss it critically must needs consider that wider audience, and how to communicate the desired subtleties. Dr. Newcombe's comments are a good step in that direction, and I'd like to see if I can add a little simplicity (if not clarity :). Manufacturing plants receive a lot of components & materials, and usually can't afford an expensive engineer to pass judgement on each item. Instead the engineer sets up 'inspection plans' and measurements with clear boundaries between 'good guys' and 'bad guys.' Then an inspector can run the test; if the item is inside the bounds, it is passed, otherwise it is rejected. Clear, simple, objective. NOT! The engineer has made the semi-subjective choice of what is 'OK' and what is not. Overwhelmingly in most cases the exact choice of the boundary is subjective, and not based on adequete data. Furthermore, no matter how much we try, we now have a sharp boundary and the inspector gets to decide the close calls, based on their judgment. The subjectivity is most obvious when the criteria involve esthetics. (I have seen a specification that said, "surface finish of castings shall be acceptable," but that was clearly a vague spec.) Without reading the article closely, I suspect that the third step - rating drugs by outcomes - comes close to an inspection procedure even if the rating scale is continuous instead of categorical. If my analogy has some validity, then anyone who has dealt with absolute boundaries that are created for someone else's ease & benefit will probably understand the inspection fallacy, and thus may also understand the difficulty in Nutt, et al.'s paper. Cheers, Jay On Nov 5, 2010, at 5:05:20 AM, Robert Newcombe wrote: > The key issue appears to be the statement in the paper 'MCDA distinguishes > between facts and value judgments about the facts'. The process that was > performed here appears to depend on 'expert opinion' alone, at every stage > of the process - deciding what are the relevant outcomes, weighting them > for their relative importance, and also rating different drugs with regard > to these outcomes. It is appropriate for the first two of these steps to > be driven by elicited opinion. But the third step should if at all > possible be closer to being directly data-driven, not just rely on the > opinions of experts who have seen the evidence. It is at this point in > the process that their arguments appear to be vulnerable. I realise that > it would be naive to imagine that doing all this in an objective way would > be as straightforward as conducting a Cochrane review on a well-defined > issue. That process is now regarded as reasonably straightforward only > because it has been done so many times, and experience has been gained. > But surely we now have a better idea than this of how to make that third > step data-driven. > > Robert G. Newcombe PhD CStat FFPH > Professor of Medical Statistics > Department of Primary Care and Public Health > Centre for Health Sciences Research > Cardiff University > 4th floor, Neuadd Meirionnydd > Heath Park, Cardiff CF14 4YS > > Tel: (+44) 29 2068 7260 > Fax: (+44) 29 2068 7236 > > Home page https://sites.google.com/site/robertgnewcombe/home > > > > > > From: "Ameen J (AT)" <[log in to unmask]> > To: [log in to unmask] > Date: 04/11/2010 21:36 > > > > The strength of this paper is in its simplicity, not to forget what > Einstein had said "Keep it Simple (KIS)".That is what modelling is mainly > about. We are yet to learn about the complexity of our surroundings and > the creation of miniture, simple and easy to understand models that can > help us better understand these complex phenomena are all welcome. > However, my comments (Ameen 1995) on a paper by Professor Chatfield are > still valid. Models are subjective and some models are better than some > others. There is no "true" model! It is not clear what the authors mean > by stating "accuracy of individuals judgments..."! in their use of a > version of Visual Analogue Scale (VAS) or a ratio scale as the authors > call it. The benefits of the use of such a scale are stated in a paper > (Coll and Ameen 2004) while the use of a four scale scoring limits its > statistical use and induces biasedness as comparison with normality > becomes difficult. In terms of bisedness, I would have liked to read much > more about the nature and the format of the pannel to ensure unbisedness. > > Another point that I would like to make is the georeferencing of the > experiment and the findings which would, to a degree, devalue the > universal scientific content of the paper. For example, the economic > impact in pricing, costs and social acceptance of drugs. > > Best wishes > > Jamal > > Coll AM, Ameen JRM & Mead D (2004). Postoperative pain assessment tools > in day surgery: literature review. Journal of Advanced Nursing. 46(2), > 124-133; > Ameen JRM (1995) Comments on Model Uncertainty, Data Mining and > Statistical Inference. J. R. Statist. Soc. A. 453 > > Prof Jamal Ameen > Senior Advisor, Ministry of Planning > KRG, Erbil > Tel: +496(750) 428 84 82 > Email: [log in to unmask] > & > Faculty of Advanced Technology > University of Glamorgan, UK > http://staff.glam.ac.uk/users/3851-jrmameen > > ________________________________________ > From: A UK-based worldwide e-mail broadcast system mailing list > [[log in to unmask]] on behalf of Maria Viskaduraki > [[log in to unmask]] > Sent: Thursday, November 04, 2010 1:32 PM > To: [log in to unmask] > > I did read the paper. The moral for me: Choose a controversial subject and > you can get through to a top journal. > The art of statistics is a separate story. > > Maria Viskaduraki > Biostatistician > Birmingham > > > -----Original Message----- > From: A UK-based worldwide e-mail broadcast system mailing list [ > mailto:[log in to unmask]] On Behalf Of Tony Greenfield > Sent: 04 November 2010 12:18 > To: [log in to unmask] > Subject: nutt > > to those allstatters who have read David Nutt's paper in the current > Lancet: > > > > I cannot believe that this was peer reviewed. > > > > what to do you think? > > > > Tony Greenfield > > You may leave the list at any time by sending the command > > SIGNOFF allstat > > to [log in to unmask], leaving the subject line blank. > > You may leave the list at any time by sending the command > > SIGNOFF allstat > > to [log in to unmask], leaving the subject line blank. > > You may leave the list at any time by sending the command > > SIGNOFF allstat > > to [log in to unmask], leaving the subject line blank. > > > You may leave the list at any time by sending the command > > SIGNOFF allstat > > to [log in to unmask], leaving the subject line blank. Jay Warner Principal Scientist Warner Consulting, Inc. 4444 North Green Bay Road Racine, WI 53404-1216 USA Ph: 262.634.9100 Fax: 262.681.1133 email: [log in to unmask] web: www.a2q.com The A2Q Method (tm) -- What do you want to improve today? You may leave the list at any time by sending the command SIGNOFF allstat to [log in to unmask], leaving the subject line blank. You may leave the list at any time by sending the command SIGNOFF allstat to [log in to unmask], leaving the subject line blank.