Table 3.

Intervention trials investigating the effect of active warming on pain.

Study	Design	Participants	Intervention	Outcomes
Kober et al., 2001 [18]	Randomized single-blinded	n = 100 with minor trauma	Warming with an electric heating blanket	Resistive heating: ↓pain, anxiety, ↑overall patient satisfaction, thermal comfort, and core temperature
		Resistive heating (n = 50, 53–67 years old)
		Passive warming (n = 50, 50–64 years old)
Kober et al., 2003 [19]	Randomized single-blinded	n = 60 with cholelithiasis	Warming with an electric heating blanket over abdomen	Active warming: ↓pain, anxiety, heart rate, and ↑skin and subcutaneous temperature
		Active warming (n = 30, 47.8 ± 18.2 years old)
		Passive warming (n = 30, 42.9 ± 21.0 years old)
Kober et al., 2003 [20]	Randomized single-blinded	n = 100 with acute renal colic	Warming with an electric blanket set to 42°C	Resistive heating: ↓pain, anxiety, nausea, vasoconstriction, heart rate, and ↑overall patient satisfaction
		Resistive heating (n = 36, 27.6 ± 6.8 years old)
		Passive warming
		(n = 38, 29.4 ± 7.1 years old)
Bertalanffy et al., 2006 [21]	Randomized single-blinded	n = 62 (all women) with pelvic pain	Warming with an electric heating blanket over abdomen	Active warming: ↓pain, anxiety, nausea, heart rate, and vasoconstriction
		Active warming (n = 29, 24.2 ± 5.1 years old)
		Passive warming (n = 33, 26.3 ± 3.8 years old)