
416 Mass. 454 (1993)
623 N.E.2d 478
ANN MARIE ROBINSON'S CASE.
Supreme Judicial Court of Massachusetts, Suffolk.
September 13, 1993.
November 23, 1993.
Present: LIACOS, C.J., WILKINS, ABRAMS, LYNCH, & GREANEY, JJ.
W. Frederick Uehlein for the insurer.
Roger J. Brunelle for the employee.
*455 LYNCH, J.
Hartford Insurance Company (insurer) appeals from a decision of a reviewing board affirming a report of an administrative judge awarding compensation under G.L.c. 152, § 34 (1992 ed.), to Ann Marie Robinson (employee). We transferred the case from the Appeals Court on our own motion and affirm the decision of the reviewing board.
We briefly summarize the facts found by the administrative judge and adopted by the reviewing board. From 1976 until March 11, 1987, the employee was employed as an occupational health nurse at Data General Corporation (employer). Beginning in October, 1985, there was a general reduction in the employer's staff. As a result of the reductions, the employee assisted many coworkers in dealing with their personal and emotional problems arising from the loss of their jobs. The employee was overwhelmed by the increased demands placed on her and the constant exposure to the emotional problems of coworkers. As a result, she lost fifty pounds, became tense, and developed tension-related physical illnesses. The parties stipulated that the employee suffers from depression and anxiety. The administrative judge determined that the employee was totally disabled from performing gainful employment and found that the employee's emotional disability was "primarily caused by a series of events occurring within her employment," such as her steadily increasing job responsibilities, work load, and increasing demands from superiors.
I. Standard of Review.
The standard of review for appeals from decisions of a reviewing board is defined in the workers' compensation statute. General Laws c. 152, § 12 (2), as appearing in St. 1985, c. 572, § 26, provided: "Any appeal from a decision by a reviewing board shall be taken pursuant to section fourteen of chapter thirty A, except that such appeal shall be filed with the appeals court of the commonwealth." General Laws c. 30A, § 14 (1992 ed.), limits the instances where a court may set aside or modify an agency's decision. See Lettich's Case, 403 Mass. 389, 395 (1988). Section 12 (2) was amended by St. 1991, c. 398, § 32A, and now provides:

*456 "Any appeal from a decision by a reviewing board shall be taken pursuant to section fourteen of chapter thirty A, except that such appeal shall be filed with the appeals court of the commonwealth and provided further that clause (e) of paragraph seven of section fourteen of chapter thirty A shall not apply to such appeals."
General Laws c. 30A, § 14 (7) (e), provides that a court may set aside or modify an agency's decision if it determines the decision is "[u]nsupported by substantial evidence." General Laws c. 30A, § 1 (6) (1992 ed.), defines "[s]ubstantial evidence" as "such evidence as a reasonable mind might accept as adequate to support a conclusion." Under the substantial evidence standard, courts were required to scrutinize the whole record to determine whether the standard had been met. Boston Edison Co. v. Boston Redevelopment Auth., 374 Mass. 37, 54 (1977).
We first decide whether the former or the present provision of § 12 (2) applies. General Laws c. 152, § 2A (1992 ed.), provides a mechanism to determine when an amendment to G.L.c. 152 will apply retroactively or prospectively. Section 2A provides:
"Every act, in amendment of this chapter, in effect on the effective date of this section or thereafter becoming effective which increases or decreases the amount or amounts of compensation payable to an injured employee or his dependents including amounts deducted for legal fees shall, for the purposes of this chapter, be deemed to be substantive in character and shall apply only to personal injuries occurring on and after the effective date of such act, unless otherwise expressly provided. Every act, in amendment of this chapter, in effect on the effective date of this section or thereafter becoming effective which is not deemed to be substantive in character within the meaning of this section shall be deemed to be procedural or remedial only, in character, and shall have application to personal injuries irrespective *457 of the date of their occurrence, unless otherwise expressly provided."[1]
Thus, all amendments not increasing or decreasing the amount of compensation are considered procedural or remedial and apply retroactively. Statute 1991, c. 398, § 107, provides that the amendment to § 12 (2), eliminating from appellate scrutiny consideration whether the decision is "[u]nsupported by substantial evidence," is procedural and thus applies retroactively.
We are constrained to set aside or modify the decision of the reviewing board only if the decision is:
"(a) In violation of constitutional provisions; or
"(b) In excess of the statutory authority or jurisdiction of the agency; or
"(c) Based on an error of law; or
"(d) Made upon unlawful procedure; or
"(f) Unwarranted by facts found by the court on the record as submitted or as amplified ... in those instances where the court is constitutionally required to make independent findings of fact; or
"(g) Arbitrary or capricious, an abuse of discretion, or otherwise not in accordance with law."
G.L.c. 30A, § 14 (7). We note, as other courts have, that these varying standards may overlap with the substantial evidence standard. As the employee correctly points out:
"Without some factual support for a decision, an agency decision would ordinarily be viewed arbitrary. If supported by substantial evidence, it is likely to be viewed by a court, reluctant to substitute its own judgment, as reasonable. Although we hesitate to say the test would yield the same results in all situations, what both standards require of an agency action is reasoned *458 decision making within the particular statutory guidelines."
Howe v. Health Facilities Appeals Bd., 20 Mass. App. Ct. 531, 537 n. 6 (1985), and authorities cited.
II. Substantive Issues.
With this standard in mind we next turn to the substantive issue raised by the insurer; first, that the employee failed to meet her burden of proof under G.L.c. 152, § 1 (7A). General Laws c. 152, § 1 (7A), as amended through St. 1985, c. 572, § 11, and St. 1986, c. 662, § 2,[2] defines "[p]ersonal injuries" within the meaning of c. 152, and provides, in part:
"Personal injuries shall include mental or emotional disabilities only where a significant contributing cause of such disability is an event or series of events occurring within the employment. No mental or emotional disability arising principally out of a bona fide, personnel action including a transfer, promotion, demotion, or termination except such action which is the intentional infliction of emotional harm shall be deemed to be a personal injury within the meaning of this chapter."
The insurer posits that the Legislature has signalled its desire that employees be put to a higher standard of proof in workers' compensation cases involving mental or emotional disability and that the employee has failed to meet that heightened standard. We do not agree.
Although the amendments to § 1 (7A) would mandate a different result than in Kelly's Case, 394 Mass. 684 (1985), *459 that does not mean that all of the court's reasoning has been supplanted. In Kelly's Case, the court indicated that none of the earlier precedents, on which the insurer now relies, "suggest[s] that entitlement to workers' compensation for emotional disability requires proof of facts in addition to those required when the disability is only physical, and we discern no basis in G.L.c. 152 for such a requirement." Id. at 686. Additionally, the court rejected "any contention that [the employee] is not entitled to workers' compensation unless her emotional disability resulted from an unusual and objectively stressful or traumatic event." Id. at 687. The court noted that it was for the Legislature "to determine, as a matter of public policy, whether one of the costs of doing business in this Commonwealth shall be the compensation of those few employees who do suffer emotional disability as a result of being laid off or transferred." Id. at 689. The 1985 and 1986 amendments, apparently, were the Legislature's response to the court's suggestion.
General Laws c. 152, § 1 (7A), as amended, still provides that mental or emotional disability arising out of a bona fide personal action shall not, with an exception not here material, be compensable.[3] Furthermore, § 1 (7A), as then amended, provided that, to recover for mental or emotional disability, the employee must demonstrate that a significant contributing cause of the disability was an event or events occurring within the employment. The insurer interprets the amendments to § 1 (7A) as requiring the employee to prove by clear and objective evidence that she was subjected to specific, identifiable, and significant events resulting in her mental disability. We do not read the statute in this manner.
What is now required is that the employee establish that a work-related event was a "significant" as opposed to a minor cause of the employee's emotional distress. Here, the administrative *460 judge accurately applied this standard by finding that the employee's "emotional disability was principally caused by a series of events occurring within her employment." Additionally, she found that the employee's "depression and resultant disability is directly and causally related to a series of stress related events which occurred at work." Although she did not use the word "significant," her conclusion is a proper application of the standard that an event of employment must be a significant contributing cause to an employee's disability.
Next, the insurer argues that, even if the administrative judge used the correct standard, the evidence was insufficient to prove that specific and identifiable events occurring within the employment were a significant contributing cause of her disability. To be compensable, an event must be "attributable to the `nature, conditions, obligations or incidents of employment; in other words, [to] employment looked at in any of its aspects.'" Zerofski's Case, 385 Mass. 590, 592 (1982), quoting Caswell's Case, 305 Mass. 500, 502 (1940). The administrative judge found, based on the employee's testimony, "that the stress placed on her from her steadily increasing job responsibilities and her constant exposure to the emotional problems of her co-workers resulted in a breakdown of her ability to cope with the demands of her job." There is no basis for us to set aside or to modify these findings.
Furthermore, there is nothing in the statute to suggest that emotional disability is compensable only if it resulted from "an unusual and objectively stressful or traumatic event." Kelly's Case, supra at 687. The finding that the employee's disability was causally related to a series of events at work is sufficient as long as those events were significant factors in bringing about the employee's disability.
The decision of the reviewing board is affirmed.
So ordered.
NOTES
[1]  This provision was amended by St. 1991, c. 398, § 16. Pursuant to St. 1991, c. 398, § 107, this amendment is deemed to be procedural.
[2]  Section 14 of St. 1991, c. 398, substituted the words "the predominant" for "a significant," and inserted a sentence providing: "If a compensable injury or disease combines with a preexisting condition, which resulted from an injury or disease not compensable under this chapter, to cause or prolong disability or a need for treatment, the resultant condition shall be compensable only to the extent such compensable injury or disease remains a major but not necessarily predominant cause of disability or need for treatment." Under St. 1991, c. 398, § 106, the amendment is substantive, thus it applies prospectively only.
[3]  The administrative judge found that the events causing the employee's injuries did not arise out of a bona fide personnel action. This finding was within the scope of the judge's competence. She could have believed that the employee's emotional injuries arose from the stress of having to deal with the effect of bona fide personnel actions on other employees.
