Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Pain
RCT 4-armed trial	84 women with moderate or greater pain in at least 4 of their last 6 cycles who experienced pain relief with non-prescription analgesics and had a history consistent with a diagnosis of primary dysmenorrhoea	Mean pain relief score after 2 days of treatment from the start of menses 3.27 with abdominal heated (to 38.9 °C) patch for about 12 hours daily plus placebo 1.95 with unheated patch plus placebo	P <0.001	Effect size not calculated	heated patch plus placebo
RCT 4-armed trial	84 women with moderate or greater pain in at least 4 of their last 6 cycles who experienced pain relief with non-prescription analgesics and had a history consistent with a diagnosis of primary dysmenorrhoea	Mean pain intensity reduction after 2 days of treatment from the start of menses 40.4 with abdominal heated (to 38.9 °C) patch for about 12 hours daily plus placebo 21.9 with unheated patch plus placebo	P <0.003	Effect size not calculated	heated patch plus placebo