How can I assess the quality of research papers/studies ?

I need to discuss the strengths and limitations of different epidemiological studies that have been employed to investigate the association between dietary fibre intake and colorectal cancer.





I really need a few pointers!

How can I assess the quality of research papers/studies ?
You need to refeer to good journals, with an Impact factor higher than 6-7





The best gastroenterology journal is called (guess?)





Gastroenterology


http://www.gastrojournal.org/





But Gut is also good.





An easy way of doing it, is to go to "Pubmed" (http://www.ncbi.nlm.nih.gov/entrez/query...





and type your key words and see what comes up!





I work in a Gastro lab. If you need any leading papers, I might be able to send them to you.





Good luck
Reply:I found this paper:





Diet and colorectal cancer: current evidence for etiology and prevention.





* Campos FG,


* Logullo Waitzberg AG,


* Kiss DR,


* Waitzberg DL,


* Habr-Gama A,


* Gama-Rodrigues J.





Department of Gastroenterologoy, Colorectal Surgery Unit, Hospital das Clinicas, University of Sao Paulo Medical School, Brazil. fgcampos@osite.com.br





The etiology of colorectal cancer (CRC) involves the interaction of cell molecular changes and environmental factors, with a great emphasis on diet components. But the paths connecting lifestyle characteristicas and the colorectal carcinogenesis remain unclear. Several risk factors are commonly found in western diets, such as high concentrations of fat and animal protein, as well as low amounts of fiber, fruits and vegetables. A large number of experimental studies have found a counteractive effect of fiber on neoplasia induction, especially in relation to fermentable fiber (wheat bran and cellulose). Epidemiological correlation studies have also indicated that a greater ingestion of vegetables, fruit, cereal and seeds is associated to a lower risk for colorectal neoplasia. Moreover, beneficial properties of fiber (especially from vegetable sources) were documented in more than half of case-control studies. Nevertheless, recent epidemiological data from longitudinal and randomized trials tended not to support this influence. Future research should evaluate what sources of fiber provide effective anti-neoplasic protection, carrying out interventional studies with specific fibers for longer periods. Red meat, processed meats, and perhaps refines carbohydrates are also implicated in CRC risk. Recommendantions to decrease red meat intake are well accepted, although the total amount and composition of specific fatty acids may have distinct roles in this setting. Current evidence favors the substitution of long and medium-chain fatty acids and arachidonic acid for short-chain fatty acids and eicosapentaenoic acid. Excess boy weight and excess energy intake inducing hyperinsulinemia have been also associated to CRC, as well as personal habits such as physical inactivy, high alcohol consumption, smoking and low consumption of folate and methionine. Thus, current recommendations for decreasing the risk of CRC include dietary measures such as increased plant food intake; the consumption of whole grains, vegetables and fruits; and reduced red meat intake.





published in Nutr Hosp. 2005 Jan-Feb;20(1):18-25.





Hope it helps
Reply:You need to understand the different types of medical studies:


case series


case-control


single blind


double blind


longitudinal


random


correlation


migrant


cohort


meta-analysis


controlled trials


observational





As well as the term "peer reviewed"





Google is your friend
Reply:A few pointers...


People:


Find out leading researchers in the field (Profs etc). Search for articles on their names. Generally only leading scientists have reviews accepted or are asked to do reviews in the better journals.





Journals:


Assess which are the leading journals in the field of interest. Rank articles from the leading journals downwards. For example, 'Entomologist monthly' may be better than 'you and your moth weekly'





Only use peer-reviewed articles. Last thing you want is to use information that is someones opinion rather than solid research based upon facts.





You could also look at the 'Impact Factors' for the journals where the reviews are published. In general, the higher the impact factor, the better the journal and harder it is to publish in that journal. It is therefore more likely that the harder-to-publish-in journals are better.
Reply:well I know nothing about the topic, but you need reliable sources right? You have to find peer-edited journals. I am assuming you are in college. Your university should have a library page.. for example my school's is lib.wayne.edu. You should be able to find yours. from there, log in and you should have a link to different journals. The problem is, you really are not supposed to be able to access them unless you are in a library or logged on to a library's site, so I don't know how else you could get them.