323Deduction for previous injury or pre-existing condition or abnormality

#### 323 Deduction for previous injury or pre-existing condition or abnormality 323 Deduction for previous injury or pre-existing condition or abnormality > > (1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality. > > > (2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence. > > > > Note. > > > > So if the degree of permanent impairment is assessed as 30% and subsection (2) operates to require a 10% reduction in that impairment to be assumed, the degree of permanent impairment is reduced from 30% to 27% (a reduction of 10%). > > > (3) The reference in subsection (2) to medical evidence is a reference to medical evidence accepted or preferred by the medical assessor in connection with the medical assessment of the matter. > > > (4) The Workers Compensation Guidelines may make provision for or with respect to the determination of the deduction required by this section. > > > (5) (Repealed) > > Note. > > Section 68B of the 1987 Act makes provision for how this section applies for the purpose of calculating workers compensation lump sum benefits for permanent impairment and associated pain and suffering in cases to which section 15, 16, 17 or 22 of the 1987 Act applies. > > **s 323:** Ins 2001 No 61, Sch 4.2 \[17\]. Am 2003 No 29, Sch 2 \[7\]; 2015 No 19, Sch 6 \[4\]; 2020 No 18, Sch 6.11\[55\].