1. بسم الله الرحمن الرحیم

2. Types of Questions

3. Types of Study

6. ? Types of Research The Level of Evidence Depends on the Question Type
Treatment
Prognosis
Diagnosis
Etiology ?
Types of Clinical Questions II
III
III IV IV
III II
III
III II IV
III II
The Level of Evidence Depends on the Question Type
RCT
Cohort
Case- control
Case Series
Cross sectional I I I I
Types of Research
Systematic Reviews
Meta-analyses

11. Appraise Are the results of the study valid? What are the results?
Will the results help in caring for my patient?

12. Step 1: Are the results Valid?
Did intervention and control groups start with the same prognosis?
1. Were patients randomized?
2. Was group allocation concealed?
3. Were patients in the study groups similar with respect to known prognostic variables?

13. Were patients randomized?

14. Was group allocation concealed?

15. Were patients in the study groups similar with respect to known prognostic variables?
: Table 1: The study groups did not differ significantly in baseline characteristics.

16. Was prognostic balance maintained as the study progressed?
4.To what extent was the study blinded?

17. Were the groups prognostically balanced at the study's completion?
5. Was follow-up complete?
6. Were patients analyzed in the groups to which they were first allocated?
7. Was the trial stopped early?

19. Are the results of this study valid?
Key validity issues for studies of Therapy:
randomization
concealed allocation
baseline similarities
blinding
follow-up complete
intention-to-treat

20. Step 2: What are the results?
How precise was the estimate of the treatment effect?
What were the confidence intervals?
P value
How large was the treatment effect? What was the relative risk reduction? What was the absolute risk reduction?

21. Statistical Precision
P-value: hypothesis, chance, type one error
CI: point-estimation, width CI of treatment effects

22. Measurment of Treatment Effects for Outcomes

23. Measurment of Treatment Effects

25. Not Clinically important Not Statistically significant
Distinction between statistical significance and clinical importance (Berry 1986)
Not Clinically important
Clinically important
True Negative
Clinically important
Null Hypothesis
Statistically
significant
Not Statistically significant

26. Size of Effectcs Clinical important effects
The distance of point estimate from null hypothesis
Statistical and clinical differences

27. How can I apply the results to patient care?
Were the study patients similar to my population of interest? Does your population match the study inclusion criteria? If not, are there compelling reasons why the results should not apply to your population?
Were all clinically important outcomes considered? What were the primary and secondary endpoints studied? Were surrogate endpoints used? Are the likely treatment benefits worth the potential harm and costs?

28. Thank You !