In the Matter of: Judith Kempton.

may not be cited except as provided by

Minn. Stat. sec. 480 A. 08, subd. 3 (1996).

 STATE OF MINNESOTA

 IN COURT OF APPEALS

 C2-97-1143

In the Matter of

the Findings of Abuse, Neglect,

or Misappropriation of Property

by Carol Peschong.

 Filed February 3, 1998

 Affirmed

 Harten, Judge

Minnesota Department of Health

File No. 73-0900-10299-2

Marlene S. Garvis, Thomas L. Cummings, Jardine, Logan & O'Brien, P.L.L.P., 2100 Piper Jaffray Tower, 444 Cedar St., St. Paul, MN 55101 (for appellant)

Hubert H. Humphrey, III, Attorney General, Susan A. Casey, Assistant Attorney General, 14th Floor NCL Tower, 445 Minnesota Street, St. Paul, MN 55101 (for respondent)

Considered and decided by Harten, Presiding Judge, Huspeni, Judge, and Klaphake, Judge.

 U N P U B L I S H E D O P I N I O N

 HARTEN, Judge

Relator Carol Peschong challenges the conclusion that she physically and mentally abused residents of the Hopkins Care Center on the grounds that it was not supported by substantial evidence and was arbitrary or capricious. We affirm.

 FACTS

Peschong was employed as a nursing assistant at the Hopkins Care Center (Center). On February 18, 1995, Peschong was assigned to orient a new nursing assistant, Lisa Luostari. Peschong and Luostari first assisted a female resident. The resident normally used a wheelchair, but could walk with assistance. Luostari testified that Peschong dragged the resident to the bathroom without allowing her to take any steps on her own, smashed the resident's elbow into the bathroom door jamb, and roughly dropped or pushed her onto the toilet. Luostari further testified that Peschong told the resident to hurry up and used profanity. Peschong denied smashing the resident's elbow into the door, pushing her onto the toilet, or using any inappropriate language. Peschong and Luostari also assisted a male resident. Luostari testified that Peschong said, "Come on [], it's time to go put your dickie in the toilet." Peschong denied making the statement.

Luostari reported the incidents to the clinical manager. The clinical manager and the director of nursing investigated the allegations by interviewing Luostari, Peschong, several other employees, and residents. On February 23, 1995, Peschong was discharged. The director of nursing reported the incidents to the Department of Health, Office of Health Facility Complaints (OHFC), indicating that Peschong had physically and mentally abused residents in violation of the Minnesota Vulnerable Adults Act, Minn. Stat. § 626.557. In May 1995, a representative of the OHFC conducted an investigation and confirmed that Peschong had physically and mentally abused Center residents.

In July 1996, a contested hearing was held before an administrative law judge (ALJ). In addition to Luostari's testimony about the incidents, other employees testified regarding Peschong's work style and treatment of residents. Two employees testified that they had seen Peschong repeatedly tap a male resident on the nose and call him "Bud." They testified that Peschong's behavior often agitated and angered the resident, but that the behavior would continue even after he asked her to stop. Employees also testified that Peschong was rough and aggressive, used profanity with residents, and residents said she was rude. Peschong denied any mistreatment. The ALJ decided that the Department of Health failed to establish that the incidents took place and concluded that Peschong's conduct was not abusive. The ALJ recommended that the commissioner reverse the conclusions of the OHFC.

Acting for the commissioner, the assistant commissioner filed Findings of Fact, Conclusions, and Order, which declined to adopt the ALJ's recommendation, instead concluding that Peschong physically and mentally abused Center residents. Peschong appeals by certiorari.

 D E C I S I O N

We may reverse or modify agency decisions if the findings, inferences, conclusions, or decisions are not supported by substantial evidence or are arbitrary or capricious. Minn. Stat. § 14.69(e), (f) (1996). The party seeking review has the burden of proving one of those statutory grounds. Markwardt v. State, Water Resources Bd., 254 N.W.2d 371, 374 (Minn. 1977). Generally, we give great deference to administrative fact-finding. Hough Transit, Ltd. v. Harig, 373 N.W.2d 327, 333 (Minn. App. 1985). Agencies enjoy a presumption of correctness, and courts must defer to their special knowledge. Reserve Mining Co. v. Herbst, 256 N.W.2d 808, 824 (Minn. 1977). The commissioner's findings are viewed in the light most favorable to the decision. Booher v. Transport Clearings, 260 N.W.2d 181, 183 (Minn. 1977).

Long-term nursing facilities must not use "verbal, mental, sexual, or physical abuse." 42 C.F.R. § 483.13(c)(1) (1996). The Minnesota Department of Health is obliged to investigate reports of abuse and neglect of nursing facility residents. 42 U.S.C. § 1395i-3(g)(1)(C) (1997). Findings of abuse must be reported to the Nursing Assistant Registry. Id. Minnesota law implements federal requirements relating to the abuse and neglect of nursing home residents by nursing assistants. Minn. Stat. § 144 A. 61, subd. 1 (1996). At the time of these incidents, federal law had not defined "abuse" by long-term care facilities. Since then, the Department of Health and Human Services has defined abuse as "the willful infliction of injury, unreasonable confinement, intimidation, or punishment with resulting physical harm, pain or mental anguish." 42 C.F.R. § 488.301 (1996). In state and federal jurisdictions, acts that clarify previously used terms, but do not change vested rights, are given retroactive effect. Nardini v. Nardini, 414 N.W.2d 184, 196 (Minn. 1987); see Landgraf v. USI Film Prods., 511 U.S. 244, 114 S. Ct. 1483 (1994) (statutes are not given retroactive effect when they impair vested rights). We treat the newly added definitions as clarifications. Carlson v. Lilyerd, 449 N.W.2d 185, 191-92 (Minn. App. 1989), review denied, (Minn. Mar. 8, 1990).

 1. Substantial Evidence

Peschong argues that the commissioner's findings and conclusions are not supported by substantial evidence. The substantial evidence test requires an evaluation of the evidence on which the commissioner relied in light of the entire record. Cable Communications Bd. v. Nor-west Cable Communications Partnership, 356 N.W.2d 658, 668 (Minn. 1984). We must affirm the decision if we find that the commissioner engaged in reasoned decision-making, even if we would have reached a different conclusion. Id. at 669. Substantial evidence means:

(1) such relevant evidence as a reasonable mind might accept as adequate to support a conclusion; (2) more than a scintilla of evidence; (3) more than "some evidence"; (4) more than "any evidence"; and (5) evidence considered in its entirety.

 Reserve Mining Co., 256 N.W.2d at 825. We must accept inferences made by the commissioner unless manifestly unjust. Id. When the agency's findings on witness credibility differ from those of the ALJ, we review the agency decision more critically. In re Occupational License of Hutchinson, 440 N.W.2d 171, 176 (Minn. App. 1989), review denied (Minn. Aug. 9, 1989).

Peschong argues that because the ALJ was in a position to hear the testimony and observe the witnesses, this court should prefer the A.L.J.'s conclusions over the commissioner's decision. Caselaw clearly states, however, that the ALJ makes only a recommendation to the commissioner, who then reviews the evidence and issues a decision. Hymanson v. City of St. Paul, 329 N.W.2d 324, 326 (Minn. 1983). The ALJ's role is subordinate to, and therefore not binding upon, the commissioner. Id.

Peschong argues that Luostari was not a credible witness. The ALJ did not make a determination on credibility, but two statements in her report infer witness credibility. First, the ALJ found that Luostari's two-day delay in reporting Peschong's behavior does not reflect on Luostari's credibility. Second, the ALJ found that a slight inconsistency in Luostari's description of the events "does not rise to an inconsistency which would decrease the believability of Luostari's statements." Peschong also argues that for several reasons the other witnesses who testified against her were not credible. The ALJ, however, did not find that any of them lacked credibility.

Mindful that the ALJ did not find that any witnesses lacked credibility, we must affirm the commissioner's decision if it is supported by substantial evidence. Luostari testified that Peschong used inappropriate language with two residents and roughly handled one resident. Other employees testified that they had seen Peschong agitate a resident by patting him on the nose and calling him "Bud," use profanity with residents, and treat residents roughly. The commissioner's findings are substantially supported by this testimony. Although Peschong offered contrary testimony, the commissioner is entitled to weigh the evidence, and we defer to the commissioner's reasoned findings of fact.

Moreover, substantial evidence exists to support the findings that the incidents of mistreatment occurred. This evidence, in turn, supports the commissioner's findings of abuse. The record permits a finding that Peschong willfully inflicted injury or intimidation upon residents. See 42 C.F.R. § 488.301 (defining abuse). Moreover, although there was no proof that Peschong's acts resulted in physical harm, the commissioner could rationally conclude that her roughness and inappropriate language caused pain or mental anguish. Id. Under our narrow standard of review, the commissioner's finding that Peschong mentally and physically abused residents of the Center is supported by substantial evidence.

 2. Arbitrary and Capricious

A decision is arbitrary and capricious if it represents the agency's will and not its judgment or is not supported by the evidence. Brinks, Inc. v. Minnesota Pub. Util. Comm'n, 355 N.W.2d 446, 452 (Minn. App. 1984). If there is room for a difference of opinion, the decision is not arbitrary and capricious, even if we do not agree with the agency's conclusions. In re License Application of Rochester Ambulance Serv., 500 N.W.2d 495, 499 (Minn. App. 1993).

The commissioner made findings of fact that were supported by the evidence, which included the testimony of credible witnesses; the findings of fact supported the

commissioner's conclusions and order. We conclude that the commissioner's decision is neither arbitrary nor capricious.

  Affirmed.