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Table 1 Sample size determination

From: HIV, immune activation and salt-sensitive hypertension (HISH): a research proposal

F tests using MANOVA for repeated measures, within–between interaction
Options Pillai V, O’Brien-Shieh Algorithm  
Analysis A priori: Compute sample Size  
Input Effect size f(v) 1
α err prob 0.05
Power (1-β err prob) 0.80
Number of groups 4
Number of measurements 3
Output Non-centrality parameter λ 22
Critical F 2.8477260
Numerator df 6.0
Denominator df 14.0
Sample size 11 per group
Lost to follow (10%) 1 per group
Total sample size 48
Actual power 0.825
Pillai V 1.0