FOREST PLOT.pptx simplify by dr saurabh maurya

forest plot interpretation

1. FOREST PLOT Presented by – Dr . Saurabh Maurya JR – 1 Department of Pharmacology & Therapeutics King George Medical University Lucknow

2. Definition : Graphical Representation of meta analysis. A forest plot is a graph that compares information from many individual clinical or scientific studies, studying the same thing.

3. They all usually have :

4. Types : Comparing difference data : eg . Mean , Absolute Risk Reduction

5. Type 2 : Comparing Ratio Data : eg . Hazard ratio Odds ratio

6. Parts of graph : Axis : a) Horizontal axis ( X axis ) : y - Scale of statistics - Relative : OR , RR x - Absolute : Absolute Risk Reduction b) Vertical Axis ( Y axis ) : - Line of null effect

7. Line of null effect :

8. 2. Horizontal Lines : - Study Lines - two ends = confidence interval (CI) - smaller CI – small line ( better ) - large CI -- longer line

9. 3. Squares : - sample size / study population - smaller square – small sample size 4. Diamond : - Summary - point estimate - If diamond touches the vt. Line, it means both groups are same.

10. 5. Study lines crossing X – axis : - means study is not statistically significant. - so they can be excluded. Disadvantage : - Can’t take account into publication bias. ( eg . Not published study )

11. THANK YOU