title: Evidence-based medicine in the wilderness: the safety of backcountry water.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Welch
mesh_terms: D000818:Animals; D003458:Cryptosporidium; D019317:Evidence-Based Medicine; D005618:Fresh Water / Q000469:parasitology*; D005872:Giardia; D006801:Humans; D009051:Mountaineering; D014871:Water Microbiology; D018508:Water Purification