We decided to review the available evidence including these recent clinical trials. Our review was limited to trials with AMS as an end point. Since assessment of AMS is subjective and potentially prone to bias, we decided to include only randomized, placebo-controlled, double-blind studies which clearly defined the diagnosis of AMS. A protocol for this review is available on the journal website (See Appendix S1, Supporting Information). In conducting and reporting

this review, we were guided by the principles of the PRISMA consensus statement (www.prisma-statement.org). Inclusion criteria are outlined in full in the protocol. Briefly, we aimed to include any randomized, double-blind, placebo-controlled trial comparing acetazolamide with placebo for the prevention of AMS. Placebo control, double blinding and a clear definition of AMS were considered selleck products essential because of the subjective nature of the symptoms of AMS and the potential for bias in uncontrolled or unblinded trials. Diagnostic criteria for AMS were this website considered to be a clear statement detailing which patients were

considered to have AMS or the reporting of scores from a validated tool for which guidelines on interpreting the score to diagnose AMS are available (eg, the Lake Louise questionnaire discussed below). A literature search was conducted using the MEDLINE, Embase, Cochrane Clinical Trials Register, and ClinicalTrials.gov databases. Searches were conducted using the key words “acetazolamide” or “Diamox” in combination with “altitude,” “acute mountain sickness,” or “high altitude headache.” Abstracts were then screened and the full text of any that were considered to possibly meet the inclusion criteria was obtained. Other systematic reviews and clinical practice guidelines were also screened for publications that might be appropriate for inclusion and any other studies referenced in publications reviewed were also considered. Language was not considered an Sulfite dehydrogenase exclusion criteria but only trials published in full were considered for inclusion. Data were

extracted from the published results by two researchers working independently (N. D. R. and A. V. B.). Data were collected and compared for consistency. Any discrepancies were resolved by mutual agreement, but if agreement could not be reached then the third researcher (W. T. A. T.) was given a casting vote. Inclusion or exclusion of studies was performed by mutual agreement once data were extracted. Bias within studies was assessed using the tool developed by the Cochrane Collaboration.[6] Our primary analysis was to compare the incidence of AMS with that of placebo. Prespecified secondary analyses were the influence of dose, maximum altitude, and rate of ascent on treatment effect and the incidence of adverse effects.