Table 1 Published randomised trials on the use of heat in the treatment of marine envenomation.

Study	N/Type	Group	Intervention	Outcome	Comments
Thomas et al8	133	Swimmers with box		Pain scores at 0, 5 and 10 minutes:	Poor randomisation technique
2001	Randomised	jellyfish (Carybdea	Hot pack v cold pack	42.3 to 31.3 to 27.5* v 38.3 to 32.8* to 36.2	due to practical difficulties
	controlled	alata) stings	Cold pack v placebo	38.3 to 32.8* to 36.2 v 38.6 to 37.7 to 38.2	Inadequate blinding
	trial		Hot pack v placebo	42.3 to 31.3* to 27.5* v 38.6 to 37.7 to 38.2	Altered outcome measures
				(*p<0.05)	after starting trial (changed
				Cessation of pain—odds ratio (95% CI):	definition of pain cessation)
			Hot pack	5.2 (1.3 to 22.8)	Not analysed on intention to
			Cold pack	0.5 (0.1 to 2.1)	treat basis
			Placebo	1.0
Nomura et al9	25 (50 stings)	Volunteers with box		Pain scores at 0, 4, 20 minutes	Potentially active substances
2002	Randomised	jellyfish (Carybdea	Hot water immersion	3.6 to 2.1* to 0.2*	(papain or vinegar) used
	paired	alata) stings	Control	3.7 to 3.2 to 1.8	as controls
	trial			(* p<0.001)	No placebo
Loten et al10	96	Swimmers with blue		Percentage with reduced pain 10, 20 minutes	Possible allocation blas,
2006	Randomised	bottle (Physalia)	Hot water immersion	53%*, 87%**	suggested by the baseline
	controlled	stings	Ice pack	32%, 33%	imbalance in initial pain
	trial			(* p = 0.039; **p = 0.002)	severity