Different types of metaanalysis

All meta-analyses should be conducted in the context of a systematic review and should analyse all appropriate data in order to reduce bias. Although many papers published in the medical literature are described as meta-analyses, such projects are not all of a similar design, quality or validity. Although, there is a continuum in the effort that can be invested in ensuring that a meta-analysis is systematic and comprehensive, there are three broad types of data that can be obtained. Information can be extracted from published reports, summary data canbecollectedfromtrialists, or individual patient data (IPD) can be obtained from trialists. These IPD projects involve the central collection, validation and re-analysis of, usually updated, 'raw' data, from all clinical trials, worldwide, that have addressed a common research question; obtained from those responsible for the original trials [13]. Although they are less common than other types of review, they are becoming increasingly used in a wide range of healthcare areas. IPD meta-analyses have an established history in cardiovascular disease and cancer, where the methodology has been developing steadily since the late 1980s. In cancer, for example, more than fifty IPD meta-analyses of screening and treatment across a wide range of solid tumour sites and haematological malignancies have been completed [14]. IPD has also been used in systematic reviews in a number of other fields including Alzheimers disease [15], dyspepsia, epilepsy [16], malaria, HIV infection [17] andhernia [18,19].

However, meta-analyses which use aggregate data either supplied directly by trialists, or more frequently extracted from published reports, are less resource-intensive and more common.

Herbal Remedies For Acid Reflux

Herbal Remedies For Acid Reflux

Gastroesophageal reflux disease is the medical term for what we know as acid reflux. Acid reflux occurs when the stomach releases its liquid back into the esophagus, causing inflammation and damage to the esophageal lining. The regurgitated acid most often consists of a few compoundsbr acid, bile, and pepsin.

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