INTRODUCTION TO SCIENTIFIC PAPERS

1. INTRODUCTION TO SCIENTIFIC PAPERS Joe Pozdol, MLIS Evans Whitaker, MD, MLIS Norris Medical Library University of Southern California 2003 Zonal Ave. Los Angeles, CA 90089-9130 pozdol@usc.edu ewhitake@usc.edu

2. Before We Begin… • Ask! • PowerPoint at www.usc.edu/nml under Key Resources for Students • Interactive questions • Handouts • Article later • Evaluation • Unwanted handouts

3. Outline For Today I. Parts of a paper A. Abstract B. Introduction/Background C. Methods D. Results E. Discussion F. References (Bibliography) II. Study types A. Primary 1. Observational 2. Experimental B. Secondary III. Group work IV. Evaluations

4. PART ISections of a published scientific paper

5. Part I Objectives • Learn the basic structure of papers • Develop an approach to reading papers • Learn how to interpret an article citation

6. The Basic Parts • Title • Abstract • Introduction • Methods • Results • Discussion • References

7. Read In This Order • Title • Abstract • Introduction/ Discussion • Methods/ Results

8. The discussion section occurs before the author presents the results of the study. • True • False

9. Which occurs first in a scientific journal article? • Abstract • Discussion • Introduction • Methods • Results

10. Abstract • Summarizes • Often only part read • Don’t act on abstracts alone • Structured abstracts are norm • Background • Methods • Results • Conclusions

11. Introduction • Context • What is known • Supporting literature (citations) • Gaps in literature • The research question • Newness • Relevance to field

12. Methods • Steps taken to • gather data • analyze data • Statistical methods • Not a “cookbook” • Replicable

13. Results • Report of data • Tables and graphs • Statistical results • No interpretation

14. Discussion • Interpretation of results • Answer to research question • Goals met? • Often includes • relation to previous research • limitations • future directions

15. Which should allow other researchers to replicate the study? • Abstract • Discussion • Introduction • Methods • Results

16. Limitations of the study are found in the… • Abstract • Discussion • Introduction • Methods • Results

17. References • List of sources cited in intro • Usually other journal articles • Previous studies in same field • Citation styles differ depending on • field of study (e.g. AMA vs. APA) • journal • EndNote and RefWorks

18. Understanding Journal Article References Weiss, PA. Does smoking marijuana contribute to the risk of developing lung cancer? Clinical Journal of Oncology Nursing. 2008;12(3):517-519. Journal Volume Number Issue Number Researcher’s Article

19. Which cannot be determined from a reference list citation? • Title of the journal • Title of the journal article • Number of pages in the journal • Number of pages in the journal article • None of the above

20. Whether marijuana use causes lung cancer is still unknown and will likely be a subject of research in the next 5 years. • True • False

21. PART IITYPES OF SCIENTIFIC PAPERS

22. Part II Objectives • Learn the common study types • Be able to extract the research question • Be able to identify an article’s study type • Be able to determine the conclusions

23. Outline For This Section • Focus on 4 study designs • Case-control • Cohort • Randomized Control Trial • Review • Narrative • Systematic • Meta Analysis

24. “3 questions to get your bearings” * * - Greenhalgh, T. (2006). How to read a paper: the basis of evidence-based medicine. Malden, MA: Blackwell • What was the research question? • What was the research design? • Was the research design appropriate to the question? Will try to find answers to 1 and 2 in excerpts of 4 articles (A-D) provided

25. Study Designs Primary Literature Observational Case-Control Cohort Experimental Randomized Control Trial Secondary Literature Narrative (Subject/Journalistic) Reviews Systematic Review Meta Analysis

26. Case-Control Patients with a disease or exposure --compared to-- Similar group without disease or exposure Best uses Rare conditions Diseases or conditions that may take a long time to develop

27. Background: DES Used in the United States from 1947 until 1971 Boston area doctors noted an unusual cancer Study compared the group with the cancer to similar people without the cancer The major difference between the cases and the controls was DES exposure

28. Example: DES and Cancer • Herbst, A.L., Ulfelder, H., & Poskanzer,D.C. (1971). Adenocarcinoma of the vagina: association of maternal stilbestrol therapy with tumor appearance in young women.NEJM, 284(16), 478-481. • Look at article: • Last sentence in Introductory area = research question • First paragraph in methods = research design

29. Why did the authors match cases and controls by the type of service mothers received?* • To reduce socioeconomic differences • To examine whether the cancer was related to infectious disease exposures • To decide if chemical disinfectants used to clean wards caused cancer • All of the above * -see page 879

30. Cohort • Two groups compared over time • One group with “exposure”, the other without the “exposure” • Best used: • when exposures can’t be controlled • when outcomes occur infrequently • when RCT is not ethical

31. Example: Smoking vs. Non-Smoking British Physicians Doll, R., Peto, R., Boreham, J., & Sutherland, I. (2004). Mortality in Relation to Smoking: 50 years' observations on male British doctors. BMJ, doi:10.1136/bmj.38142.554479.AE 50 years (and counting) Cohort Study of British doctors Most recent of a series of reports Compared health outcomes of smokers vs. health outcomes of non-smokers Research question = Research design =

32. When was there enough evidence from this study to show the link between smoking and lung cancer? • 1954 • 1966 • 1978 • 1991

33. Randomized Control Trial A treatment group is compared to a control group Group members are assigned randomly Best uses: Drug therapies Medical treatments

34. Example: Smoking cessation intervention • An, L.C., Klatt, C., Perry, C.L., Lein, E.B., Hennrikus, D.J., et al. (2008). The RealU online cessation intervention for college smokers: a randomized control trial. Preventive Medicine, 47(2)194-199. • Look at the article: • The last paragraph of the introduction - research question • The last paragraph of the introduction - research design • Study flow chart - pg. 196

35. 25,000 UM students were recruited by emailHow many UM students ended up in the intervention group? 1. 24,007 2. 2,407 3. 257 4. 107 5. 7

36. 30 What percent of RealU participants had 30 days of no smoking at week 30? • 100% • 80% • 60% • 40% • 20% • none

37. Narrative (Journalistic/Subject) Reviews • The “traditional” or “classic” review • “Review” limit in Ovid/PubMed includes: • Narrative reviews • Systematic reviews • Authors choose articles included • Author bias is a concern – research verifies this effect

38. Systematic Review • Reproducible methods to find and select articles are included • Should include both inclusion and exclusion criteria • Why? Decrease author bias

39. Example: Is HPV Vaccine Cost-Effective? • Techakehakij, W., Feldman, R.D. (2008). Cost-effectiveness of HPV vaccination compared to Pap smear screening on a national scale: a literature review. Vaccine, doi:10.1016/j.vaccine.2008.09.036 • Look at article: • Pg. 2, Section 3.1, first paragraph = research question • Pg. 3, Section 4.1, first to third paragraphs = research design

40. 30 It is recommended that HPV vaccine be given as a 3 shot series. How much do 3 doses of vaccine cost? • $500-$1000 • $300-$500 • $200-$300 • $100-$200

41. Meta Analysis Similar to Systematic Review except… Numeric data from separate studies combined in meta analysis Uses statistical/mathematical methods to combine numerical data from studies Combining data increases the confidence we have in the conclusions reached by a meta analysis

42. GROUP WORK

43. Group Work • Groups of 3 • Everyone in group gets same article (#1, 2, 3, OR 4) • Spend 10 min. working together on questions • Class discussion

44. Additional slides

45. * - used loosely here; not distinguishing between correlation and causation (in medicine etiology is used for the cause of a disease or condition) ** - can results of an RCT be applied to groups that do not match the study group?

46. Thanks for your attention • We will post these slides on the Student Portal on the Norris Medical Library website • Contact us with questions • Joe Pozdol – pozdol@usc.edu • Evans Whitaker – ewhitake@usc.edu • Please complete evaluations!

47. References An, L.C., Klatt, C., Perry, C.L., Lein, E.B., Hennrikus, D.J., et al. (2008). The RealU online cessation intervention for college smokers: a randomized control trial. Preventive Medicine, 47(2)194-199. Doll, R., Peto, R., Boreham, J., & Sutherland, I. (2004). Mortality in Relation to Smoking: 50 years' observations on male British doctors. BMJ, doi:10.1136/bmj.38142.554479.AE Gallicchio, L., Boyd, K., Matanoski, G., et al. (2008). Carotenoids and the risk of developing lung cancer: A systematic review. Am.J.Clin. Nutrit., 88, 372-383. Gordon, C.M., Carey, M.P., & Carey, K.B. (1997). Effects of a drinking event on behavioral skills and condom attitudes in men: Implications for HIV risk from a controlled experiment. Health Psychology, 16(5), 490-495. Greenhalgh, T. (2006). How to read a paper: the basis of evidence- based medicine. Malden, MA: Blackwell. Guyatt, G., Rennie, D. (eds.). (2001). User’s guides to the medical literature: essentials of evidence-based clinical practice. Chicago: AMA Press.

48. References Herbst, A.L., Ulfelder, H., & Poskanzer,D.C. (1971). Adenocarcinoma of the vagina: association of maternal stilbestrol therapy with tumor appearance in young women. NEJM, 284(16), 478-481. Metcalf, B.S., Voss, L.D., Hosking, J., & Wilkin, J.T. (2008). Physical activity at the government-recommended level and obesity- relatedhealth outcomes: a longitudinal study(Early Bird 37).Archives of Diseases of Childhood (Early Bird 37). 93,722-777. Peled, R. Carmil, D., Siboni-Samocha, O., & Shoham-Vardi, I. (2008). Breast cancer, psychological distress and life events among young women. BMC Cancer, 8, 245-250.