TABLE 9

Effects of Zinc Therapy of Persistent Diarrhea

ReferenceCountryStool Frequency ReductionProbability of Diarrhea Continuation
Sachdev et al18 (1990)India22% lower frequency19% shorter duration
Roy et al21 (1998)BangladeshNot reported7% shorter duration
Khatun et al34 (2001)Bangladesh7% lower frequency17% shorter duration
Bhutta et al33 (1999)Pakistan9% lower frequency14% reduction in probability
Penny et al35 (1999)PeruNot reported19% shorter duration
Bhandari et al36 (2002)Nepal12% lower frequency22% reduction in probability
  • Average stool frequency reduction = 12.5%; average shortening of duration = 15.5%; average probability of diarrhea reduction = 18.0%. Variances in data reporting of outcome measures: For this meta-analysis, shortening of diarrhea duration was defined as the percentage ratio of the mean number of days of diarrhea in each study group. It was then reported as a shorter percentage of time with diarrhea for one group or the other. Probability of diarrhea duration was calculated by authors using various statistical approaches, such as the odds ratio, risk ratio, or hazards ratio. This difference in statistic negated a comparison in the meta-analysis. Stool frequency reduction was calculated by taking a ratio of the average diarrhea frequency in some studies per 24 hours or by the risk ratio of the mean number of stools in the first 4 days of another study. Lower stool output was calculated, in 2 studies, by taking a ratio of the total stool weight per kilogram of body weight and reporting the median. The ratio of the median was then taken. The resulting percentage was interpreted as a lowering of stool output in one group or the other. In another study, it was reported as the total stool output until the last first formed stool, measured in grams per kilogram for each group. The geometric mean was then taken and a ratio between groups obtained. The group with the lower percentage was interpreted as a lowering of stool output in one group or another.