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Table 3 Power analysis

From: Evaluating real-time internet therapy and online self-help for problematic alcohol consumers: a three-arm RCT protocol

F tests – ANOVA: Fixed effects, omnibus, one-way
Analysis: A priori: Compute required sample size  
Input: Effect size f 0.25
  α error probability 0.05
  Power (1-β error probability) 0.80
  Number of groups 3
Output: Non-centrality parameter λ 9.938
  Critical F 3.054
  Numerator df 2
  Denominator df 156
  Total sample size 159
  Actual power 0.805