Table 3

Treatments effect on the primary and secondary outcomes measured once per period (N=120 surgeries, 30 surgeons)

OutcomeCooling vest
(N=60 surgeries)
No cooling vest
(N=60 surgeries)
Difference in means
(vest minus no vest)
(95% CI)
P value
Primary outcome
Thermal comfort
range 0–10
4.5±0.196.6±0.19−2.1 (−2.7 to 1.6)*<0.001
Sensitivity analysis
Median (Q1, Q3)
4.0 (3.5, 5.0)7.0 (6.0, 7.0)Proportional OR†
16 (6.7 to 39)
Secondary outcomes
Average MST33.0±0.0933.2±0.09−0.23 (−0.40 to 0.06)0.011
Average CBT‡36.1±0.1236.2±0.12−0.13 (−0.33 to 0.07)0.194
C3B PST Score69.4±0.8369.4±0.830.03 (−2.44 to 2.51)*0.979
C3B VMT Score range 0–7058.4±1.4357.5±1.420.88 (−2.25 to 4.01)*0.569
Perception of sweat-soaked clothing range 0–101.4±0.394.3±0.38−2.91 (−3.75 to 2.07)<0.001
Fatigue range 0–102.3±0.263.3±0.25−0.95 (−1.63 to 0.28)0.007
Median (Q1, Q3)Median (Q1, Q3)Proportional OR†
Borg perceived exertion range 6–2013 (11, 13)13 (12, 15)2.3 (1.15 to 4.48)0.019
Sensitivity analysisMean±SEMean±SEDifference in means
Borg perceived exertion12.4±0.2713.2±0.27−0.78 (−1.46 to 0.09)0.028
  • Difference in means (95% CI) for the cooling vest versus no cooling vest was estimated from a repeated measures linear model with an AR (1) correlation structure adjusting for duration of the case.

  • *Adjusting for preoperative measurements.

  • †Proportional OR for the cooling vest versus no cooling vest was estimated from a generalised estimating equation proportional odds model with an independence correlation structure accounting for within-surgeon correlation.

  • ‡n=1 surgery was not included as the thermometer was malfunctioning.

  • C3B, Cleveland Clinic Cognitive Battery; CBT, core body temperature; MST, mean skin temperature; PST, processing speed test; VMT, visual memory test.