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Forest plot of studies included in meta-analysis assessing whether water treatment was associated with symptomatic cholera. Studies were stratified by whether they assessed chlorination, boiling, or nonspecific report of water treatment. The summary odds ratio was calculated using random effects models. Heterogeneity is described using the Cochran Q test and the I2 statistic. Abbreviations: CI, confidence interval; df, degrees of freedom; IV, inverse variance; SE, standard error.
