This is not surprising: the latest bibliographic ...

In our systematic review and meta-analysis, we found a high degree of heterogeneity between trials on the effectiveness nekon'yuhirovannoho >> << pneumococcal polysaccharide vaccine in prevention of a number of clinical cases. Much of this heterogeneity can be explained by

differences in methodological quality of trials. We found little evidence of protection of the elderly >> << or adults with chronic respiratory diseases for which pneumococcal vaccine is recommended in many industrialized countries. Tests of higher quality (ie, double-blind design and adequate concealment of allocation) generally show

little evidence that the strattera cost protective effect of vaccine, regardless of the study population and setting. The first meta-analysis of studies of pneumococcal polysaccharide vaccine, published in 1994, reported a protective effect on the final

predictable and pneumococcal pneumonia. Since then, numerous meta-analyzes were published, some of which are aimed at specific groups or the results of (a >> << meta-analysis is given in Annex 3, at

). Several meta-analyzes reported protective effect of vaccines on all causes of pneumonia in subgroups such as low-risk

groups or people with low incomes. ,,

Some of the earlier meta-analyzes agreed with our finding no conclusive evidence for vaccine associated with a reduced risk >> << of all-cause pneumonia, especially in elderly or chronically ill people. ,,,,

Conclusions for other decisions, often contradictory, especially for invasive pneumococcal infections. ,,,,

Last Cochrane review found evidence supporting the effectiveness of vaccines against invasive pneumococcal infection, reporting a combined ratio of treatment

0. 26 (95% CI 0. 15BЂ "0. 46). This finding contrasts with our result (combined RR 0. 90, 95% CI 0. 46BЂ. "1 77) and significantly

due to the inclusion in Cochrane reviews, in 1977, research involving Papua New Guinea Highlanders

in 1947, research involving older people in New York. We excluded the Papua New Guinea study, so that the material considered for the diagnosis of invasive pulmonary diseases included aspiration and that access to medical and diagnostic

procedures were limited. We excluded New York

research from our analysis of invasive pneumococcal infections, since a large number of participants volunteered to be vaccinated

were not randomly distributed in the vaccine group. Of the 17 meta-analyzes of pneumococcal polysaccharide vaccine, which we identified, 13 assessed quality of trials (usually

composite score) and 10 studies used for quality assessment and sensitivity analysis excluded studies with the lowest quality ratings >> << . However, no previous meta-analysis is formally study the quality of their analysis as a means of >> << explore the causes of heterogeneity of results, as we did. This is not surprising: the latest bibliographic research 272 meta-analysis of clinical trials

found that 140 (52%) rated the quality of components research, but only 66 (24%) stratified analysis for quality testing . You can expect that the observation study, due to their nature, would be more likely than randomized controlled trial

show the protective effect of vaccine. The situation observed in the literature on influenza vaccination, where

cohort study showed a significant reduction in mortality from all causes, in contrast to the results of randomized controlled trials. These conflicting results may be explained by selection bias, if vaccinated individuals were at lower risk results >> << than unvaccinated people. Studies in the U.S. recorded substantial racial and ethnic differences in the absorption of vaccination and

revealed that some positions and preferences are important factors for absorption prevention

in general. ,

These relationships are also important predictors of outcome: participants of clinical trials that adhere to prescribed drugs

Does active treatment or placebo, found that mortality compared with those who do not follow

prescribed medications. ,

On the other hand, people with a skeptical attitude to health increased mortality, possibly due to a higher level

unhealthy lifestyle. Most observational studies of pneumococcal polysaccharide vaccine reported large protective effect. For example, recently caseBЂ "control analysis of long-care setting in Austria have found strong evidence (p

0. 0001) to reduce the risk of pneumonia (odds ratio 0. 28) and death (odds ratio 0. 27). Even within the oversight of research, some of them showed little effect. A large cohort study in the U.S. showed little evidence

protective effect of vaccine against pneumonia in the elderly, but it shows a protective effect against >> << pneumococcal bacteremia. Conflicting results between observational studies and clinical trials of lower and higher methodological quality artwork

difficulties in interpreting results of studies on the risk of errors. Empirical evidence and theoretical considerations support the view that the test above methodological quality will provide results

closer to the truth, the lower the quality of research. ,,

Meta-analysis can not prove that it is necessary in this case, since other factors associated with both quality testing

and the results could confuse the analysis. For example, the immunogenicity of different antigens of pneumococcus vaccine

. changes and differences in the distribution of serotypes of different studies can be expected to introduce some heterogeneity

Notably, when we restricted the analysis to studies of higher quality, we found that between investigators heterogeneity was reduced,

which opposes the presence of important mixed. Interestingly, the blinding was more important than allocation concealment >>. << No, no dazzling allocation concealment is important for mortality from all causes. This is in accordance with

recent study that examined 146 meta-analysis of clinical trials with different results. During the trials with subjective results, the effect estimates exaggerated when there was no blinding or concealment >> << distribution was not enough, however, there was no sign of a shift in research to results, including mortality from all reasons. Fedson,

in 2003, argued that clinical trials of pneumococcal polysaccharide vaccine were BЂњdestined initially be inconclusiveBЂ "

because they suffered from methodological problems and were too small to reliably show the effect of pneumonia on all causes. We included

several studies published since then and found that, when we restricted our analysis of studies of higher quality, essential >> << beneficial effect on all causes of pneumonia were excluded with certainty. This does not apply to some other results

particular invasive pneumococcal disease, as analyzes were based on multiple trials and multiple events. Mangtani and colleagues

argued that the pneumococcal polysaccharide vaccine can prevent pneumococcal bacteremia but not pneumonia because of poor

, Manufacturing opsonizing antibodies. Our results are not inconsistent with this opportunity, but also provide little evidence for this. Concern that our meta-analysis of high-quality research does not rule out harmful effects of pneumococcal polysaccharide vaccine >> << to prospective pneumonia or pneumonia from all causes. A large cohort study from the U.S. also showed increased risk >> << among the elderly. Our results for all causes of pneumonia were strongly influenced by a double-blind study in HIV-infected adults in Uganda

, which showed a significant, harmful effects of vaccines. The authors proposed a mechanism associated with HIV infection, which may explain the harmful effects. However, they also suggested

which may be more common, yet unknown, explain. . << >>