Pages within the "support" section:
14.1 Individuals and their attributes
The population relevant to the dietary change or intervention under assessment should already have been identified in earlier stages of assessment (i.e. at Brafo Tiers 1 and 2). For quantitative integration of risks and benefits using the Qalibra framework (Brafo Tiers 3 and 4) it is necessary to know the age structure of this population, i.e. the proportions of individuals in different age groups, unless the assessment is for a single individual (see section 13). If the calculation will be based on data for individuals from a dietary survey, I sf in Equations (1)-(4) can be used to scale the dietary survey population up to the total population of interest.
The current age CA of each individual is a required input, shown explicitly in Equations (1)-(4). Data on other attributes of each individual (e.g. sex, body weight, etc.) may also be required if they are known to influence any of the other input parameters, e.g. if they appear as covariates in dose-response relationships.
When conducting an assessment for a population (as opposed to for a single individual), the calculations are performed for a sample of individuals from that population (and then scaled up to the full population using the scaling factor I sf if desired). These individual characteristics can be data on real individuals (e.g. from a dietary survey) or simulated from a model based on summary statistics for the population (e.g. age distribution). If the sample of individuals is too small, then the results may be unduly influenced by chance inclusion of different individuals or different combinations of parameter values (a form of sampling uncertainty), and to adequately represent variability of intakes among individuals with similar attributes. It is therefore important to ensure that the sample of individuals (prior to scaling up) is large enough to provide stable estimates of the assessment outputs, i.e. the estimates should not change materially if the size of the sample is increased.