Reference no: EM132308682

Critical Review of Scientific Journal Article

Health care, including nutrition care, relies on scientific evidence to inform professional practice. Much of this evidence is produced from research studies presented in scientific journal articles. In the field of Nutrition, examples of credible, respected journals include:

The Journal of the Academy of Nutrition and Dietetics

The Journal of Nutrition

The American Journal of Clinical Nutrition

Research articles published in scientific journals have been reviewed and accepted by experts in the field and are generally considered reliable. Nonetheless, it is important for readers to critically evaluate the article before drawing their own conclusions on the findings.

A critical review of a journal article is an evaluation of an article's strengths,weaknesses and validity. The reader makes a value judgment of the article by carefully considering different aspects of the study and the overall "take-home" message.

At first, reading research articles is difficult because some terms and statistical descriptions seem technical. This assignment is intended to introduce you to the critical review process and it focuses on guiding you through the main components of an article.

Read the assigned article and answer the following questions. Type your answers on this sheet, save it as a Word or PDF document with your name in the file name, and submit to the critical review submission site. Use your own words for answers. Answers containing quoted or copied material earn no points.

The article is posted next to this Word document on the course Moodle page.

1. List the biographical information given about the authors(university or institute of employment.) Does the university department or institute seem appropriate for the study's topic? For example, it would raise concern if a professor of Geology wrote an article about dietary treatment for heart disease.

2. Define the reason for this investigation. What research evidence on this topic already exists and why is the current study needed?

3. What is the research hypothesis?

4. Research studies are often advertised and interested individuals contact the recruitment office to inquire about participation. A telephone screening followed by an office screening are common. In this study, how many individuals completed a phone screening and how many were included in final data analysis? What percentage of the initial screening group does the final group represent?

5. What is stated about approval of this study protocol for compliance with ethical standards and the process of obtaining informed consent from the participants?

6. Was the assignment of participants to treatment group randomized? What is a possible result of not randomizing? For example, if the researchers assigned all women to treatment A and all men to treatment B?

7. Table 1. Were average measurements of weight, age, BMI, etc. significantly different between the treatment groups at the start of the study? Why are these measurements important to obtain before treatments are administered?

8. Were participants blinded to treatment assignment? The term blinding refers to keeping participants, investigators, or assessors (those collecting outcome data) unaware of an assigned intervention, so that they are not influenced by that knowledge. Why is blinding easier to accomplish in a medication trial vs. a food/diet study?

9. What is a possible result of participants knowing they are receiving an active treatment vs. a placebo? For example, if you volunteered for a research study and knew you were receiving a medication thought to enhance mental function, do you think you might expect to perform better in class and possibly change your behavior to meet your expectations? Would you be more compliant taking the active medication vs. the placebo exactly as instructed? Google search "Hawthorne Effect" in the context of research for more information.

10. Methods. List the main outcome measurementscollected from participants. At what time points were these data collected?

11. Recall that p values are a measure of uncertainty and they indicate the probability of the study result occurring by chance. Thus, if a statistical test in a certain study showed a relationship between sun exposure and blood vitamin D levels with a p value of 0.001, the probability of that result showing up by chance is 0.1% (very low). A low p value indicates high confidence that the result is real. P values less than0.05 are usually considered statistically significant. From Table 2, which variables (at which time point) show a statistically significant difference between the almond-enriched and nut-free groups?

12. What are the authors' major findings and conclusions?

13. Describe two strengths and three limitations of the study listed by the authors.List a different, additional limitation or strength that you noticed.

14. Who funded ("supported") the study? Do you believe a study's source of support can influence the published results? What would be your response if, after reading a research article on chocolate consumption and reduced heart disease, you read that the study was funded by Hershey's vs. the US National Institutes of Health?

Note that funding source is only one item to consider in a critical review and that private industry funding does not automatically indicate bias.Much research would never be performed without support by private companies and foundations (General Mills, The California Almond Board, The National Pork Producers Council, etc.)