1. Scientific Writing Top 5:
3. More than v. over
Do not use over to describe relative amounts.
More than = greater than
Over = physically above
wrong: She raised over $500.
right: She raised more than $500.

2. Scientific Writing Top 5:
4. Compared to v. compared with
Compare to = to point out similarities between different things
Compare with** (used more often in science) = to point out differences between similar things
ex: “Shall I compare thee to a summer’s day?”
ex: Brain tumors are relatively rare compared with more common cancers, such as those of the lung, breast, and prostate.

3. More writing humor…
In an office: AFTER TEA BREAK STAFF SHOULD EMPTY THE TEAPOT AND STAND UPSIDE DOWN ON THE DRAINING BOARD. Outside a secondhand shop: WE EXCHANGE ANYTHING -- BICYCLES, WASHING MACHINES, ETC. WHY NOT BRING YOUR WIFE ALONG AND GET A WONDERFUL BARGAIN? Notice in health food shop window: CLOSED DUE TO ILLNESS. Spotted in a safari park: ELEPHANTS PLEASE STAY IN YOUR CAR.

4. Scientific Writing Top 5:
5. That v. which
“That” is the restrictive (defining) pronoun
“Which” is the nonrestrictive (non-defining) pronoun
What’s the difference between these two?
The vial that contained her DNA was lost.
The vial, which contained her DNA, was lost.

5. Scientific Writing Top 5:
That/which
Example: Other disorders which have been found to co-occur with diabetes include heart disease and foot problems.
that

6. Scientific Writing More on that/which
Key question: Is your clause essential or non-essential?
THAT: The essential clause cannot be eliminated without changing the meaning of the sentence.
WHICH: The non-essential clause can be eliminated without altering the basic meaning of the sentence (and must be set off by commas).

7. Scientific Writing More on that/which
The lawn mower that is broken is in the garage. (Identifies which* lawn mower.)
The lawn mower, which is broken, is in the garage. (Adds a fact about the only mower in question).
* note use of which as adjective! (v. pronoun)

8. Scientific Writing More on that/which
“Careful writers, watchful for small conveniences, go which-hunting, remove the defining whiches, and by doing so improve their work.” –Strunk and White

9. Scientific Writing: More on that/which
From physicist Richard Feynman:
“When we say we are a pile of atoms, we do not mean we are merely a pile of atoms because a pile of atoms which is not repeated from one to the other might well have the possibilities which you see before you in the mirror.”
that
that

10. Scientific Writing More on that/which
Another example:
Stroke incidence data are obtained from sources, which use the ICD (International Code of Diseases) classification systems.

11. Scientific Writing More on that/which
Stroke incidence data are obtained from sources…?
Is the clause essential? Is it defining the subject?
Yes!
use “that”

12. Scientific Writing
Stroke incidence data are obtained from sources, which use the ICD (International Code of Diseases) classification systems.
that

13. More writing humor…
Seen during a conference: FOR ANYONE WHO HAS CHILDREN AND DOESN'T KNOW IT, THERE IS A DAY CARE ON THE FIRST FLOOR.
Notice in a farmer's field: THE FARMER ALLOWS WALKERS TO CROSS THE FIELD FOR FREE, BUT THE BULL CHARGES.
Message on a leaflet: IF YOU CANNOT READ, THIS LEAFLET WILL TELL YOU HOW TO GET LESSONS.
On a repair shop door: WE CAN REPAIR ANYTHING. (PLEASE KNOCK HARD ON THE DOOR - THE BELL DOESN'T WORK.)

14. More writing humor…
The peacemaking meeting scheduled for today has been cancelled due to a conflict.
Remember in prayer the many who are sick of our community. Smile at someone who is hard to love. Say "Hell" to someone who doesn't care much About you. (I think they meant hello) 
Don't let worry kill you off – let the Church help.

15. More humor…
Next Thursday there will be tryouts for the choir.  They need all the help they can get.
Irving and Jessica were married on October 24 in the church.  So ends a friendship that began in their school days.
Scouts are saving aluminum cans, bottles and other items to be recycled.Proceeds will be used to cripple children.
Please place your donation in the envelope along with the deceased person you want remembered.

16. More humor…
This evening at 7 PM there will be a hymn singing in the park across from the Church. Bring a blanket and come prepared to sin.  (Do you think they meant sing?)
The pastor would appreciate it if the ladies of the congregation would lend him their electric girdles for the pancake breakfast next Sunday.
Low Self Esteem Support Group will meet Thursday at 7 PM. Please use the back door.
The ladies of the Church have cast off clothing of every kind.  They may be seen in the basement on Friday afternoon.

17. Scientific Writing Preview to next time…
Next time you read a newspaper, pay attention to the following:
1. How many letters are in an average word?
2. How many words are in an average sentence?
3. How many sentences are in an average paragraph?

18. Critical appraisal of research paper or journal article

19. What is Critical Appraisal?
Critical appraisal is the process of carefully
And systematically analyze the research paper to
judge its trustworthiness, and its value and
relevance in a particular context.
“Critical appraisal is the process of systematically
examining research evidence to assess its validity,
results, and relevance before using it to inform a
decision” (Hill and Spittlehouse, 2001, p.1).

20. When should you Critically Appraise?
Conducting literature reviews for grant proposals for new project
Evaluating the effectiveness, costs, and benefits of health programs, Intervention etc.,
Establishing new innovative in the health programs
To set right the lacunae while Implementing health policies policies
and Public health decision making

21. The Critical Appraisal aims to help people develop the necessary skills to make sense of scientific evidence based on validity, results and relevance.

22. Research involves gathering of data ,
collection of data and analysis of the data to
produce meaningful information.
However, many of the research are not in
good quality and many studies are biased and
their results are untrue.
This can lead us to draw false conclusions

23. Critical appraisal is an essential step in the process of putting research into practice.
Asking questions about an article’s research methodology
Scrutinizing its data collection and analysis methods
And evaluating how its findings are presented will help you to determine whether that article’s conclusions should influence practical decision-making.

24. Different research questions require different study designs
Different research questions require different study designs. For example the best design for studies evaluating the effectiveness of an intervention or treatment is a Randomized controlled trial.

25. Studies are also subject to Bias, Confounders and it is important that researchers take steps to minimize this bias &confounders. For example, use of a Control group, Randomization and blinding.

26. Odds ratios, Risk ratios/Relative risk and number needed to treat etc
Odds ratios, Risk ratios/Relative risk and number needed to treat etc., are methods of analysing results in order to determine if an intervention is effective.

27. Read the abstract Are your issues discussed there?
What are the main findings of the research?
Do you want to know more after reading the abstract?
Does it address a related question?
Are there reasons to doubt the findings without reading the whole article?

28. Read the Introduction and Discussion
The introduction and discussion sections will help you to identify the key concepts, goals, subjects, and themes of the research.

29. Methodology section
The Methodology will give you a step-by-step description of exactly how the study was carried out.
Where the study was done?
From whom the data was collected ?
Is it primary or secondary data
And how the data was collected?

30. How good is the data?
Does the study adequately control for differences between the groups being compared?
Are the statistical methods appropriate?
Is the sample large enough to produce significant results?

31. How good are the measures?
Do the measures accurately reflect what the researcher was trying to measure (validity)?
How clear and appropriate are these measures? (Too broad? Too narrow? Ambiguous?)
Are they actual measures or proxy measures?
Are the measures well established in either prior research or through pilot testing by the researcher, or are they ad hoc?

32. What are the author’s conclusions?
Compare the abstract to the Discussion The discussion section is more detailed and precise than the abstract, and will explain the limitations of the research and possible implications which are not mentioned in the abstract.

33. Compare the raw data given in the tables with the results analyzed in the discussion and conclusions
Are the results reported in the conclusions
consistent with what is reported in the tables?
Is the interpretation consistent with what the
actual findings were?

34. How well are the results related to other research on the same topic?
In the discussion or conclusions section, is there a review of how these results compare or contrast with prior research?
If this report found something different from previous research, then it’s important to question on appraising the reliability of the findings.

35. Critical Appraisal of an article on Harm / Risk (Cohort Study)
Are the results of the study valid?
Primary Guides
Was the exposure status clearly defined and measured?
How was the outcome of interest measured?
What was the follow up time and was it adequate to measure the outcome of interest?
Was the outcome measured in the same way for both exposed & not exposed?
Secondary Guides
How much was the attrition? (Loss to follow up)
Are there confounders that the investigator did not address?

36. 3. Will the results help me?
2. What were the results?
How strong is the association between exposure and outcome? ( Look for Relative Risk, Hazard ratio)
How precise is the estimates of the risk ? (Look for 95% CI and p value for statistical test of significance)
3. Will the results help me?
Are the results applicable to my population?
What is the magnitude of the risk ?
Should I attempt to stop the exposure?

37. Acknowledgement
1.Dr.B.W.C.Sathyasekaran, Professor,SRMC&RI(DU)
Refence:
1. Basic epidemiology R.Beaglehole,R.Bonita,T.Kjellstrom
2 World health organization.Health research methodology:Aguide for training in researh methods
3.Oxford text book of public health
4.Oxman et al User’Guides to Medical literature,JAMA,Nov.1993-vol
5. Guyatt et al User’Guides to Medical literature, JAMA.dec.1993-vol270No.21,2598
6. Levin et al User’Guides to Medical literature,JAMA,May.1994-Vol 271 No.20,1615
7. Handout on workshop on epidemiology at SRMC&RI(2006,2007,2008)