ABSTRACT
BACKGROUND: Probiotics are currently under focus for their immune improvement function. Many studies have been performed to assess the potential efficacy of probiotics in allergic disease, viral disease, respiratory disease, as well as gastrointestinal disease. This study performed a systematic review to determine the effects of probiotics on the prevention of the common cold. METHODS: We searched MEDLINE (PubMed), EMBASE, CINAHL, and Cochrane CENTRAL for studies released through June 2011. Two authors independently extracted the data. To assess the risk of bias of included literatures, Cochrane Collaboration's risk of bias tool was used. RESULTS: We identified 10 studies in 7 articles. A total 2,894 participants, 1,588 in the probiotics group and 1,306 in the control group, were included. The effect of probiotics on the prevention of the common cold had a relative risk (RR) of 0.92 (95% CI, 0.85 to 1.00, I2 = 26%). In the subgroup analysis, the RR of administration of probiotics for 3 months or less was 0.82 (95% CI, 0.70 to 0.97). The RR of administration of probiotics over 3 months was 1.00 (95% CI, 0.92 to 1.09). The RR of administration of probiotics without any active intervention (vitamin and mineral) was 0.87 (95% CI, 0.78 to 0.97). CONCLUSION: In this meta-analysis, there was marginal effect of probiotics on the prevention of the common cold. The results implied that probiotics had a modest effect in common cold reduction. The balance of benefit and harms needs to be considered when using probiotics for common cold prevention.
Subject(s)
Bias , Common Cold , Gastrointestinal Diseases , Probiotics , Virus DiseasesABSTRACT
BACKGROUND: In reporting results of case-control studies, odds ratios are useful methods of reporting findings. However, odds ratios are often misinterpreted in the literature and by general readers. METHODS: We searched all original articles which were published in the Korean Journal of Family Medicine from 1980 to May 2011 and identified those that report "odds ratios." Misinterpretation of odds ratios as relative risks has been identified. Estimated risk ratios were calculated when possible and compared with odds ratios. RESULTS: One hundred and twenty-eight articles using odds ratios were identified. Among those, 122 articles were analyzed for the frequency of misinterpretation of odds ratios as relative risks. Twenty-two reports out of these 122 articles misinterpreted odds ratios as relative risks. The percentage of misinterpreting reports decreased over years. Seventy-seven reports were analyzed to compare the estimated risk ratios with odds ratios. In most of these articles, odds ratios were greater than estimated risk ratios, 60% of which had larger than 20% standardized differences. CONCLUSION: In reports published in the Korean Journal of Family Medicine, odds ratios are frequently used. They were misinterpreted in part of the reports, although decreasing trends over years were observed.