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To evaluate the evidence of the supplements vitamin C and vitamin E for treatment and prevention of cancer.Systematic review of trials and meta-analysis. DATA SOURCES AND MAIN RESULTS: Thirty-eight studies showed scant evidence that vitamin C or vitamin E beneficially affects survival. In the ATBC Cancer Prevention Study Group, no statistically significant effect of treatment was seen for any cancer individually, and our pooled relative risk (regardless of tumor type) for alpha-tocopherol alone was 0.91 (95% confidence interval [CI]: 0.74, 1.12). All cause mortality was not significant. In the Linxian General Population Trial, the relative risks for cancer death for vitamin C (combined with molybdenum) was 1.06 (95% CI: 0.92, 1.21) and for vitamin E (combined with beta-carotene and selenium) was 0.87 (95% CI: 0.76, 1.00). We identified only 3 studies that reported statistically significant beneficial results: vitamin C (in combination with BCG) was found to be beneficial in a single trial of bladder cancer and vitamin E (in combination with omega-3 fatty acid) increased survival in patients with advanced cancer. In the ATBC trial, in analyses of 6 individual cancers, the prevention of prostate cancer in subjects treated with alpha-tocopherol was statistically significant (RR=0.64, 95% CI: 0.44, 0.94).The systematic review of the literature does not support the hypothesis that the use of supplements of vitamin C or vitamin E in the doses tested helps prevent and/or treat cancer in the populations tested. There were isolated findings of benefit, which require confirmation.

Acute Otitis Media (AOM), a viral or bacterial infection of the ear, is the most common childhood infection for which antibiotics are prescribed in the United States. In 2001, the Southern California Evidence-based Practice Center conducted a systematic review of the evidence comparing treatments of AOM.This review updates the 2001 review findings on diagnosis and treatment of uncomplicated AOM, assesses the evidence for treatment of recurrent AOM, and assesses the impact of the heptavalent pneumococcal conjugate (PCV7) vaccine on the microbiology of AOM.Searches of PubMed® and the Cochrane databases were conducted from January 1998 to July 2010 using the same search strategies used for the 2001 report, with the addition of terms not considered in the 2001 review. The Web of Science was also searched for citations of the 2001 report and its peer-reviewed publications.After review by two investigators against pre-determined inclusion/exclusion criteria, we included existing systematic reviews and randomized controlled clinical trials for assessment of treatment efficacy and safety. Pooled analysis was performed for comparisons with three or more trials.Few studies were found that examined the accuracy and precision of the diagnosis of AOM. Since PCV7's introduction, AOM microbiology has shifted significantly, with Streptococcus pneumoniae becoming less prevalent and Haemophilus influenzae (HF) increasing in importance. For uncomplicated AOM, pooled analysis indicates that nine children (95% CI: 6, 20) would need to be treated with ampicillin or amoxicillin rather than placebo to note a difference in the rate of clinical success. However, in four studies of delayed treatment approaches for uncomplicated AOM, two had higher rates of clinical success with immediate antibiotic therapy while two did not, and in three studies, a marked decrease in antibiotic utilization was noted. We are unable to draw definitive conclusions regarding the comparative effectiveness of different antibiotics for AOM in children with recurrent otitis media (ROM). For ROM, long-term antibiotic administration will decrease AOM episodes from 3 to 1.5 for every 12 months of treatment per otitis prone child during active treatment (95% CI: 1.2, 2.1); however, potential consequences of long-term treatment need to be considered. Data were insufficient to draw conclusions about comparative effectiveness of different treatment strategies in subgroups of children with uncomplicated AOM. Adverse events were generally more frequent for amoxicillin-clavulanate than for cefdinir, ceftriaxone, or azithromycin. Higher quality studies and improved reporting of study characteristics related to quality are needed to provide definitive conclusions for AOM and ROM treatment options.

Although several agents are available to treat osteoporosis, the relative efficacy and toxicity of these agents when used to prevent fractures has not been well described.To compare the benefits in fracture reduction and the harms from adverse events of various therapies for osteoporosis.MEDLINE (1966 to November 2007) and other selected databases were searched for English-language studies.For the efficacy analysis, investigators selected studies that reported the rate of or risk for fractures. For the adverse event analysis, they selected studies that reported the relationship between an agent and cardiovascular, thromboembolic, or upper gastrointestinal events; malignant conditions; and osteonecrosis.Using a standardized protocol, investigators abstracted data on fractures and adverse events, agents and comparators, study design, and variables of methodological quality.Good evidence suggests that alendronate, etidronate, ibandronate, risedronate, zoledronic acid, estrogen, parathyroid hormone (1-34), and raloxifene prevent vertebral fractures more than placebo; the evidence for calcitonin was fair. Good evidence suggests that alendronate, risedronate, and estrogen prevent hip fractures more than placebo; the evidence for zoledronic acid was fair. The effects of vitamin D varied with dose, analogue, and study population for both vertebral and hip fractures. Raloxifene, estrogen, and estrogen-progestin increased the risk for thromboembolic events, and etidronate increased the risk for esophageal ulcerations and gastrointestinal perforations, ulcerations, and bleeding.Few studies have directly compared different agents or classes of agents used to treat osteoporosis.Although good evidence suggests that many agents are effective in preventing osteoporotic fractures, the data are insufficient to determine the relative efficacy or safety of these agents.