Sec. 1. 39-A MRSA §213, sub-§2, as enacted by PL 1991, c. 885, Pt. A, §8 and as affected by §§9 to 11, is amended to read:

2. Threshold adjustment. Effective January 1, 1998 and every other January 1st thereafter, the board, using an independent actuarial review based upon actuarially sound data and methodology, must adjust the 15% impairment threshold established in subsection 1 so that 25% of all cases with permanent impairment will be expected to exceed the threshold and 75% of all cases with permanent impairment will be expected to be less than the threshold. The actuarial review must include all cases receiving permanent impairment ratings on or after January 1, 1993, irrespective of date of injury, but may utilize a cutoff date of 90 days prior to each adjustment date to permit the collection and analysis of data. The data must be adjusted to reflect ultimate loss development. In order to ensure the accuracy of the data, the board shall require that all cases involving permanent injury, including those settled pursuant to section 352, include an impairment rating performed in accordance with the guidelines adopted by the board and either agreed to by the parties or determined by the board reflecting only permanent impairment that results from a work injury, including permanent impairment that exists as a result of the injury's having aggravated or accelerated a preexisting condition or injury.__The impairment ratings may not reflect permanent impairment to the body parts or conditions not medically affected by the work injury even if those impairments or conditions combine with the work injury to give rise to a compensable disability for the purposes of section 201, subsection 4. Each adjusted threshold is applicable to all cases with dates of injury on or after the date of adjustment and prior to the date of the next adjustment.

The data used by the board for the purpose described in this subsection must reflect or may be adjusted to reflect only that permanent impairment that results from a work injury, including permanent impairment that exists as a result of the injury's having aggravated or accelerated a preexisting condition or injury.__The data may not reflect permanent impairment to body parts or conditions not affected by the work injury even if those preexisting conditions or injuries combine with the work injury to give rise to a compensable disability for the purposes of section 201, subsection 4.

These standards apply with like force to individual permanent impairment assessments performed for the purposes of determining whether an employee is eligible for partial incapacity benefits for the duration of the disability in accordance with this subsection and subsection 1.