| 2,000,000 | |
| 1,500,000 | |
| 1,000,000 | |
| 500,000 | |
| 0 | |
| 1995 | |
| Published Articles | |
| Medline, # Indexed | |
| Embase, # Indexed | |
| Biosis, # Indexed | |
| Unpublished, Approximate |
However, if we wanted to answer the question posed to Dr. Asclepius "Can Trykillum cause Stryasipus?" could a definitive answer be gleaned from research of the literature? Several problems immediately come to mind.
PROBLEM 1
One is the enormous amount of unpublished information available. It has been estimated that over 2,000,000 published articles are added each year to just the biomedical literature and many of these are not indexed, and therefore are not that easily retrievable. Estimates vary on the amount of actual indexed articles, but the figure probably would fall somewhere between 40 and 60 percent of those published. Some contend the majority of the published material from peer review journals is indexed, which helps to offset this large gap.
PROBLEM 2
The second problem is the large amount of unpublished studies and trials. Some estimate this to be as high as a third of the published ones. Many factors enter into this complex problem. However, most agree publication bias in its myriad forms is the major culprit. To illustrate this point, let's suppose that one tablespoon a day of Trykillum had been fed to 600 rats for one year in a controlled clinical trial. At the end of the trial, no differences were observed in rats fed Trykillum and the 600 control rats fed a normal diet. Findings that conclude with "no effect" are not particularly glamorous and chances are a report of this trial would not be published. However, this finding would be of considerable importance to our expert witness for the defense.
PROBLEM 3
A third major problem to giving a definitive answer to our Trykillum question is an outgrowth of the first two--a lack of consensus in the scientific community. It is not unusual for a special conference to be held with hundreds of experts meeting to decide a single question and when the symposium ends they are not any nearer an answer than before they met and therefore there are no published proceedings. Touted as a new way to reach consensus, meta-analysis, which aggregates the results of several trials, has proved to be at times very helpful and at other times very controversial and often investigators are not able to agree on the methodology, much less the results. An even more dramatic problem stems from the scientific method itself. Because science progresses incrementally, not rapidly, seeming contradictions creep into the literature when it is taken study by study.
These three problems are very formidable. In order to answer our Trykillum question, we will have to undertake an exhaustive search of the scientific literature, locate the unpublished findings and allow for the lack of consensus in the scientific community. We are frequently asked just such a question and at MTI this is how we proceed:
SUGGESTION FOR PROBLEM 1
After formulating our search strategy, the first step in our quest is an online search. We would probably begin with a cursory search of MEDLINE, TOXLINE, and EMBASE. Then our investigation would proceed with a manual search of INDEX MEDICUS and SCIENCE CITATION INDEX materials prior to 1996 that are not indexed online. Additional references are found by checking the bibliographies of key articles, monographs, and important reference works. This would take care of a large portion of the published literature.
SUGGESTION FOR PROBLEM 2
The next phase is more difficult, locating the unpublished information. The best place to start is to check the material unearthed in phase one. Authors often mention unpublished clinical trials, case control studies, or single case reports. A second source is clinical trial registries that exist for several research areas; one example is the Oxford Database of Perinatal Trials, that covers the years 1940-1984. A third possibility is to examine the published literature for names of scientists and research institutions and then personally contact them to discuss unpublished findings. You may even be able to obtain a written statement from them regarding the trial or study.
SUGGESTION FOR PROBLEM 3
The third problem, lack of consensus in the scientific community, is not insurmountable, but almost. Your best hope for finding a composite view of the lack of consensus may be the popular press. Many researchers are quite "media-savvy" and write their own press releases or when no symposium consensus has been reached the Society will issue a press release or post a statement on its internet home page. This will help to confirm that there is no consensus or may identify the owners of the various dissenting opinions and give you some additional leads.
After all is said and done and we have a three-foot mountain of paper, have we answered the question "Can Trykillum cause Stryasipus?" We're not sure but we are certain once our client's expert witness wades through this treasure chest of trials, studies, review literature, and documents, an expert opinion will be forthcoming and we will be closer in our quest for toxic truth.
Complete Bibliography Available Upon Request
The U.S. Environmental Protection Agency has released the final report titled Air Quality Criteria for Particulate Matter which evaluates the latest scientific information pertaining to health and environmental effects associated with airborne particulate matter. The complete document is available on the internet at: http://www.EPA.gov/ORD
The American Petroleum Institute (API) has recently made available their report titled Summary of Produced Water Toxicity Identification Evaluation Research, June 1996. The report summarizes the results of a three-part study to evaluate the ability of EPA proposed toxicity identification evaluations (TIEs) to determine the potential toxicants in produced water from oil and gas production operations in various locations. Factors affecting the results were identified as well as potential toxicants. Suggestions for improving TIE procedures are included. 102 pages. Contact Suzanne Covello at API for ordering information; phone: (202) 682-8319 or fax: (202) 682-8270.
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