Until genetic Mendelian randomisation studies were performed that introduced genetic factors as instrumental variables to predict biomarkers, it was unclear whether the observed association was causal (i.e. whether CRP causally affects the risk of cardiovascular disease or whether it is merely a marker for a previous cardiovascular).
Phylogenetic statistics of new EPIC markers are presented in comparison (Table 1) with those from nuclear markers developed for previous phylogenetic studies of Burseraceae (ETS: Weeks and Simpson, 2007; ITS: Gostel and Weeks, unpublished).
The results for HPV 16 and 18 in women of ages eligible for cervical screening consistently exceeded the proportion of women found to be HPV DNA positive in a recent study of residual cervical smear samples (Kitchener et al, 2006), as expected for a persistent marker of previous infection.
No statistical significant difference was observed for haematological parameters, serological markers of previous viral hepatitis (type B or C) and syphilis.
Nonetheless, trends in new HIV diagnoses have been used as a marker for HIV incidence in previous studies in Taiwan [39] and Australia [40], [41], and have been consistent with trends in estimates of HIV incidence in San Francisco based on other methods [42].
The EGF receptor expression by IHC has been discharged as predictive marker for response, but the previous data has assessed the receptor status in full populations and not in relation to the mutational status.
We used the direct agglutination test as a marker for infection, as in previous epidemiological studies, 16 19 28 29 30 because the low incidence of visceral leishmaniasis precluded its use as primary outcome.
Education of the head of household was used as a surrogate marker for socioeconomic status, as previous research from Hai had shown that this was a key determinant in explaining the between-household variation in expenditure (Adult Morbidity and Mortality Project Team, 2003).
Although annexin V positivity of cells has generally been considered as a marker for apoptosis, in a previous study however, we have demonstrated that this is not absolute as such and that membrane phospholipid flip-flop can be reversible [ 23], which is supported in this study by the observation that complete inhibition of caspases by Z-VAD-FMK did not affect this phenotype.
