https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-122
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-123
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-120
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-118
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-124
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-126
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-121
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-14-119
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