Estimating impact of presenteeism
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The cost of presenteeism can be seen as ‘deadweight salary’ – salary being paid without work being produced. 
Utilising a salary-based conversion approach to estimate the economic burden related to presenteeism is 
well-established in the econometric literature :cite:p:`Kigozi2017`.

In the OECD SPHeP-NCD model, one year of full-time equivalent presenteeism equals one year of full-time 
absenteeism/one year of lost salary. In terms of valuation, one full-time equivalent year of presenteeism is valued in 
terms of an annual average salary for a full time worker. In other words, if five years of full-time employment 
are lost due to presenteeism in a given country and year, then the economic burden due to presenteeism in the same year and country 
is equivalent to five times the corresponding average salary.