Posted on 09/24/2012 at 08:47:52 AM by Suzanne PriceBy Darren Early
The ASN/AJCN-CJCN author workshop in Beijing, China got off to a good start today. Dr. Dennis Bier, Editor-in-Chief of The American Journal of Clinical Nutrition began today's session with a presentation on understanding nutrition evidence for publication. He explained that a formal systematic approach to evaluating evidence in nutrition is necessary because even experts in the field disagree. He indicated that the standards for evidence in nutrition really should be the same as those in “harder” sciences like chemistry and physics. The hierarchy of evidence runs from opinions of respected authorities at the bottom of the scale to meta-analyses with original data at the top. How a question is investigated can lead to different answers; Dr. Bier provided the example of the effects of β-carotene intake on CVD mortality, for which cohort studies show a protective effect of β-carotene but trials show a harmful effect. He also described foods as the data and nutrients as the hypotheses. In addition, he outlined the strengths and weaknesses of randomized controlled trials compared with those of observational studies.
Dr. Bier concluded his presentation by discussing reviews. He pointed out that traditional narrative reviews have some serious problems, such as being subjective and prone to author bias and often lacking study quality assessment. An interesting and lively discussion ensued among the Chinese workshop attendees over the correct translation into Chinese of the term narrative review. The consensus seemed to be that traditional review was a better term. The alternative to traditional narrative reviews are formal systematic reviews, which use systematic and explicit a priori methods to identify, select, and collect data. Dr. Bier also explained that a meta-analysis consisted of the statistical aspects of a systematic review. He cautioned that systematic reviews and meta-analyses cannot make the results better than the original data.
The day's other sessions focused on various scientific topics, such as outcomes as determinants of journal publication priority, how to select a research topic in clinical nutrition studies, different clinical study designs for translational medicine, and power calculations for randomized controlled trials and cohort studies in clinical nutrition. Tomorrow's sessions will shift to publishing and cover such topics as selecting the right journal, writing strategies and readable prose, and trends in digital publishing in the United States. Read the previous blog post previewing this event and watch the YouTube video.