Mean and Mean difference are the two key statistical measures used in the statistical analysis. Both are essential for meta-analysis as well. Mean and Mean difference are used for the interpretation of a large set of values into a single number which explains the heterogeneity and variation among the individual values. However, one of a common challenge in meta-analysis is the unavailability of this data (mean and standard deviation).
Q & A Forum
Meta Analysis
Q: What is a P value, and how is it interpreted in the context of Cochrane reviews?
The P value refers the probability of getting the observed effect (stronger effect) under the assumption of null hypothesis is true. Cochrane reviews state that the null hypothesis typically assumes:
- No observed effect of the intervention, or
- No differences between the two studies observed (no heterogeneity).
A less P value states that the observed effect is not likely to be occurred by chance, presenting evidence against the null hypothesis.
References:
Cochrane Handbook for Systematic Reviews of Interventions. (2011). 12.4.2 P values and statistical significance. The Cochrane Collaboration. Retrieved from
https://handbook-5-1.cochrane.org/chapter_12/12_4_2_p_values_and_statistical_significance.htm