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Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献- Implications for Rehabilitation
This review is the first to systematically appraise the literature to answer the question what evidence exists to inform clinical decision making in relation to the language or communication attributes of graphic symbol based communication aids? The review establishes that there is a paucity of evidence from studies and that these decisions must thus be based on other information and factors.
The review does establish a small number of language or communication attributes of symbol communication aids, but no synthesis of the results of these studies was possible. This review thus suggests that vocabulary design and organization, symbol system and encoding method, and the choice of vocabulary selection method are attributes that clinicians may carefully review in order to inform decisions.
Clinicians encountering symbol vocabulary packages claiming to be ‘evidence based’ should query the nature of this evidence.
The rehabilitation research community should debate and develop appropriate research designs that will facilitate future robust studies investigating the effect of specific language or communication attributes of communication aids.