Is the apparent decrease in injury and illness rates in construction the result of changes in reporting?

Injury rates in all industries and in construction in particular have been declining. Inconsistencies in the information suggest some of the apparent decrease may be due to changes in the ways injuries are treated, misclassification of employees, or underreporting. Lost-time injury rates for the largest construction employers declined by as much as 92% between 1988 and 1999.