Mass. Gen. Laws ch. 217, § 29F

The register of the Worcester probate and family court may, with the approval of the chief justice of the probate and family court, designate 6 employees as deputy assistant registers with the same powers as assistant registers and with the approval of the chief justice remove a deputy assistant register. The deputy assistant register shall receive additional compensation in an amount equal to 15 per cent of the annual salary of the Worcester county register of probate.