The search performed in May 2013 yielded six articles pertinent to the topic (Table 1) – five randomised controlled trials (RCTs, level I evidence) (1–5), and one case series (level IV evidence) (6). Four RCTs showed that the infection rates and status of wound healing in tap water therapy were similar to the normal saline solution group (P >0·05) and the culture results from the wounds in both groups showed no significant finding in colony counts (P >0·05). Furthermore,tap water therapy may be more cost-effective (2–5). Only one RCT revealed that the infection rates in tap water therapy were significantly lower than that in normal saline solution group (P