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Table 3 Assumptions and detectable effect sizes informing sample size for the project

From: Optimizing treatment protocols for spinal manipulative therapy: study protocol for a randomized trial

  Assumptions for outcome measures
Stiffness (N) Multifidus activation (mm) Oswestry Numeric Pain Rating
Assumption
 Mean (SD) 5.55 (1.60) 2.60 (0.124) 24.3 (14.9) 5.06 (2.12)
 Pre-post score correlation 0.80 0.70 0.70 0.45
 MCID or hypothesized effect size from prior work 0.40 0.074 6.0 2.0
Type of effect Detectable effect size
 Main effect 0.37 0.034 4.12 0.76
 Pairwise interaction 0.74 0.068 8.24 1.53
 Conditional comparison 0.53 0.048 5.83 1.08
 Main effect in 50% of participants 0.53 0.045 5.83 1.08
 Interaction in 50% of participants 1.05 0.091 11.65 2.16