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Table 3 Adjustment of baseline pain level differences using the ANCOVA method

From: Evaluation of different doses of transcutaneous nerve stimulation for pain relief during labour: a randomized controlled trial

Group Mean error* Difference (95% CI)
TENS 1 6.514a 0.300 5.913 to 7.115
TENS 2 5.382a 0.315 4.750 to 6.013
Placebo 9.200a 0.308 8.583 to 9.816
  1. Data are visual analogue scale (VAS) mean values
  2. TENS transcutaneous electrical nerve stimulation, CI confidence interval
  3. *error values obtained from ANCOVA method
  4. aThe covariates that appear in the model are evaluated with the following values: pain VAS at baseline = 7269. The dependent variable is VAS after 30 min