For each site, the random residual εij was obtained and subsequently standardized using the standard deviations SD εij) of residuals across all SNPs.
Overall rates were age standardized using the World Health Organization standard population "Europe".
Incidence rates were standardized using the direct standardization method [ 20] for event rates and using the whole population of Iran [ 21] as a standard population.
All ASRs were standardized using the world standard population [ 31], and the weights were taken from the population distribution of the world standard population.
The assay was standardized using the DEQUAS external standard.
Individual tumor sample gene expression was standardized using the mean and standard deviation of the reference.
At each monitor the measurements were log-transformed and then standardized using the mean and standard deviation at that monitor.
To calculate this metric, the measurements at each monitor were log-transformed (because concentrations were right-skewed) and standardized using the mean and standard deviation at that monitor.
The assay was standardized using the p24 antigen standard provided by the National Institute for Biological Standards and Control (NIBSC, Herts, UK).
In preparation for linking, first names and addresses were standardized using the US Census Bureau's data standardization software GDRIVER [US Bureau of the Census, 1999].
The data were age standardized using the European population of 2008 as standard.
