19.2 Methodology
19.2.1 Literature Search Strategy
An extensive literature search using multiple databases (CINAHL, EMBASE, MEDLINE, Web of Science, and PsycINFO) covering the years 2000 – 2011 was initially used to identify all published literature related to animals and experimental traumatic brain injury. Specific subject headings related to animals and experimental traumatic brain injury (TBI) were used as the search terms for each database. Using a specific database’s subject heading allowed for all other terms in the database’s subject heading hierarchy related to traumatic brain injury to also be included in order to broaden the search. The database subject headings included: brain damage, chronic; traumatic brain injury; acquired brain injury; concussion; head trauma; head injury; non-traumatic brain injury; animal; model; experimental; and neuroprotection. Unpublished data or studies were not included and the search was limited to articles written in English. Studies focused on ischemic brain injury/ischemia, strokes, or non-traumatic brain injury were also excluded.
19.2.2 Study Inclusion
Studies that used either experimental (randomized trials) or non-experimental designs (prospective and retrospective, descriptive or observational, and cases studies) were included. Studies related to a specific topic but not identified by the original five databases were sought in review articles, meta-analyses, systematic reviews, or in selected study articles and included. Background information was drawn from the grey literature and peer reviewed articles.
19.2.3 Data Extraction
When an article was selected for full review, the following data was extracted: authors, year of publication, location where study was conducted, sample size, details regarding the animals studied (i.e. type of animal, type of injury, severity, source, sex, age, time since injury), treatment, outcome measures, and results. Articles which did not meet the definition of a TBI or which did not involve animals were excluded. Articles evaluating similar treatments were summarized using large tables and descriptive reviews.