Common-Effect Inverse-Variance Calculator
Audit independent difference-scale estimates, normal intervals, weights and Q-based heterogeneity summaries.
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Calculation results
Combined estimate: 2
Standard error: 0.707107
95% lower limit: 0.614096
95% upper limit: 3.3859
Q: 2
Degrees of freedom: 1
Q-based I² (%): 50
Study weights in input order (%): 50, 50
Assumptions and limits
Common-effect inverse-variance synthesis of independent difference-scale estimates with known or adequately estimated standard errors. Normal 95% interval. Do not enter raw risk ratios or overlapping samples. This does not choose a defensible synthesis model, assess bias, or fit a random-effects model. Q-based I² is descriptive and particularly uncertain with few studies. Maximum 30 studies; SE must be from 1e-10 to 1e10.
Cochrane: meta-analysis · Read the practical guide · Download blank worksheet (TXT)