Medical Researchers at the University of Sydney in Australia Examined

Medical researchers at the University of Sydney in Australia examined data from several cohort studies and several case-control studies regarding links between vaccines and autism.Overall,these studies included more than 1.25 million children from four different countries and vaccines for five different diseases.The conclusion of this paper indicates that there is no link between vaccines and autism.This work was published in the peer-reviewed journal Vaccine,and there is no evidence that the researchers at the University of Sydney have any conflict of interest with vaccines or treatment of autistic children.
Briefly describe this type of study and research (including if it is basic or applied research)and evaluate the strength of the researchers' claim that there is no link between vaccines and autism.List four lines of evidence to support your assertion.