OPINION ON REMAND
Opinion by
Justice SUE LAGARDE (Retired).In our original opinion in this case,2 we held that Debi Rose’s claim against Garland Community Hospital for negligent credentialing was not a health care liability claim governed by the Medical Liability and Insurance Improvement Act (MLI-IA).3 On November 5, 2004, the Texas Supreme Court held that “a claim for negligent credentialing is a claim against a health care provider for a departure from an accepted standard of health care, and as such it is a health care liability claim that carries all the statutory and common law burdens associated therewith.” Garland Cmty. Hosp. v. Rose, 156 S.W.3d 541, 547 (Tex.2004). The supreme court reversed our judgment and remanded the case to us for further proceedings. Id.
On remand, the narrow issue we must decide is whether Rose’s expert report constituted a good faith effort to comply with the MLIIA. See id. at 547. Supplemental briefing on remand was permitted. Having reviewed Rose’s expert report, we hold the trial court did not abuse its discretion in concluding the report did not constitute a good faith effort to comply with the statute. Consequently, we affirm the trial court’s order dismissing Rose’s case against the hospital.
Background
The facts of this case are set out in our original opinion and in the supreme court’s opinion. Accordingly, we will not repeat them, except as necessary to our analysis.
Two separate affidavits were before the trial court and are before this Court: one *355dated April 10, 2001 and one dated July 10, 2001. Both affidavits were by Robert A. Ersek, M.D. The trial court considered both affidavits. Likewise, we consider both affidavits and will sometimes refer to them together as “Rose’s expert report.”
The April 10, 2001 report speaks only to medical treatment and not to negligent credentialing. The July 10, 2001 report states, in relevant part:
I have reviewed the treatment records of Debi Rose from James H. Fowler and the Cosmetic Surgery Center of North Dallas beginning on October 30, 1998 and ending on July 14, 1999. As stated in my April 10, 2001 report, a hospital/patient relationship existed between Garland Community Hospital and Debi Rose. The standard of care requires hospitals to do the following:
1. vigorously investigate complaints and allegations of medical negligence by patients against physicians who have privileges at the hospital;
2. ascertain a physician’s qualifications and ensure that a physician has the proper training before permitting him/her to perform surgical procedures;
3. to limit, curtail or restrict a physician’s privileges where multiple complaints and/or allegations of medical negligence are lodged against a physician or to supervise that physician during surgery.
I have concluded that Garland Community Hospital breached the standard of care in the following areas:
1.Garland Community Hospital knew or should have known of multiple prior incidents involving poor surgical skills on the part of Dr. James H. Fowler and took no action to prevent or restrict Dr. Fowler’s surgical privileges;
2. Dr. Fowler, as an Ear, Nose and Throat specialist, is not board certified in plastic surgery and should not have been permitted to perform plastic surgery. There was a failure of credentialing on the part of Garland Community Hospital for permitting Dr. Fowler to perform plastic surgery.
3. To the extent that the nurses and surgical staff participated and acquiesced in the performance of plastic surgery by Dr. Fowler, Garland Community Hospital incurred liability for same.
The trial court granted the hospital’s motion to dismiss, pursuant to section 13.01 of the MLIIA, on the ground Rose had not made a good faith effort to comply with the MLIIA’s requirement that she timely file an expert report. Rose, 87 S.W.3d at 189. Rose appeals from that dismissal.
Standard of Review and Applicable Law
The issue for the trial court was whether Rose’s expert report represents a good-faith effort to comply with the statutory definition of an expert report. See Bowie Mem’l Hosp. v. Wright, 79 S.W.3d 48, 51 (Tex.2002) (citing Tex.Rev.Civ. Stat. Ann. art. 4590i, § 13.01(i); Am. Transitional Care Ctrs. of Tex., Inc. v. Palacios, 46 S.W.3d 873, 878 (Tex.2001)). In its order of dismissal, the trial court found that “[n]either the April 10 nor the July 10, 2001 report states the causal relationship, if any, between the alleged failure of [the hospital] in connection with its credentialing activities and the injury, harm or damages claimed.” The trial court also found, even considering both the April 10 and July 10, 2001 affidavits together, the affidavits do not satisfy the requirements of article 4590i.
*356We review a trial court’s order dismissing a claim for failure to comply with section 13.01(d)’s expert-report requirements under an abuse of discretion standard. Id. (citing Palacios, 46 S.W.3d at 878). And we review a trial court’s decision about whether a report constitutes a good-faith effort to comply with the MLIIA under an abuse of discretion standard. See id. (citing Palacios, 46 S.W.3d at 878). A trial court abuses its discretion if it acts in an arbitrary or unreasonable manner without reference to any guiding rules or principles. Id. (citing Downer v. Aquamarine Operators, Inc., 701 S.W.2d 238, 241-42 (Tex.1985)). When reviewing matters committed to the trial court’s discretion, a court of appeals may not substitute its own judgment for that of the trial court. See id. (citing Flores v. Fourth Court of Appeals, 777 S.W.2d 38, 41 (Tex.1989)).
A negligent credentialing claim involves a specialized standard of care. Rose, 156 S.W.3d at 546 (citing Mills v. Angel, 995 S.W.2d 262, 275 (Tex.App.-Texarkana 1999, no pet.)). Therefore, expert testimony is required to establish liability because procedures ordinarily used by a hospital to evaluate staff privileges are not within the realm of a juror’s ordinary experience. See Mills, 995 S.W.2d at 275. Medical experts are not necessarily credentialing experts. In fact, a credentialing expert need not be a physician but may be a witness who is familiar with the standard of care for credentialing because of training and experience. See id. (citing Lopez v. Cent. Plains Reg’l Hosp., 859 S.W.2d 600, 603-04 (Tex.App.-Amarillo 1993, no writ), disapproved on other grounds by St. Luke’s Episcopal Hosp. v. Agbor, 952 S.W.2d 503, 509 n. 1 (Tex.1997)).
The relevant statute defines an expert report as “a written report by an expert that provides a fair summary of the expert’s opinions ... regarding applicable standards of care, the manner in which the care rendered ... failed to meet the standards, and the causal relationship between that failure and the injury, harm, or damages claimed.” Palacios, 46 S.W.3d at 877 (quoting Tex. Civ. Stat. AnN. art. 4590i, § 13.01(r)(6)). Because the statute focuses on what the report discusses, the only information relevant to the inquiry is within the four corners of the document. See id. at 878.4 A trial court should look no further than the report in conducting a section 13.01(i) inquiry. Id.
A report need not marshal all of the plaintiffs proof, but it must include the expert’s opinion on each of the elements identified in the statute. Id. at 878-79 (citing Hart v. Wright, 16 S.W.3d 872, 877 (Tex.App.-Fort Worth 2000, pet. denied)). To constitute a good-faith effort, a report must provide enough information to fulfill two purposes: (1) it must inform the defendant of the specific conduct the plaintiff has called into question; and (2) it must provide a basis for the trial court to conclude the claims have merit. Wright, 19 S.W.3d at 52 (citing Palacios, 46 S.W.3d at 879). A report that merely states the expert’s conclusions about the standard of care, breach, and causation does not fulfill these two purposes. Palacios, 46 S.W.3d at 879. The expert must explain the basis of his statements to link his conclusions to the facts. Wright, 19 S.W.3d at 52 (quoting Earle v. Ratliff, 998 S.W.2d 882, 890 (Tex.1999)).
Analysis
Nowhere in either affidavit is there a fair summary of the expert’s opin*357ions regarding the causal relationship between the hospital’s failure to meet the specialized standard of care for credentialing and the injury, harm, or damages claimed. See Palacios, 46 S.W.3d at 877. In relevant part, the April 10, 2001 affidavit contains the following about causation:
The failure to utilize the appropriate procedures as outlined above constitutes negligence and gross negligence on the part of Dr. James H. Fowler and on the part of the facility where the treatment took place, Garland Community Hospital. Said failures were the proximate cause of Ms. Rose’s deformed abdomen, overly large breast augmentation, irregularities in her hips, thighs, arms, and shoulders, as well as the staph infection.
The causation referenced above refers to the causal link between the alleged negligent medical treatment and Rose’s injuries — it does not go to the causal link between the alleged negligent credentialing of Dr. Fowler by the hospital and Rose’s injuries. And the July 10, 2001 affidavit contains no language about such causation. Neither affidavit states there were multiple previous complaints or allegations by patients of medical negligence against Dr. Fowler, which, if they had been investigated, would have been found to be meritorious and would have led to restriction of Dr. Fowler’s privileges. Perhaps the complaints and allegations would have been unsustained as lacking merit. We may not infer causation. See Wright, 79 S.W.3d at 53 (stating that the report must include the required information within its four corners).
Because Rose’s expert report lacks information linking the “expert’s” conclusion of negligent credentialing to the hospital’s alleged breach or to Rose’s damages, the trial court could have reasonably determined the report was conclusory. See id. (citing Palacios, 46 S.W.3d at 880; Earle, 998 S.W.2d at 890). A conclusory report does not meet the MLIIA’s requirements because it does not satisfy the Pa-lacios test. Id. (citing Palacios, 46 S.W.3d at 879). When an expert report’s conclu-sory statements do not put the defendant or the trial court on notice of the eom-plained-of conduct, section 13.01(i) affords the trial court no discretion but to conclude the report does not represent a good-faith effort to provide a fair summary of the specialized credentialing standard of care, how it was breached, and how it caused plaintiffs injuries, as section 13.01(r)(6) requires. See Palacios, 46 S.W.3d at 880. Accordingly, we hold the trial court did not abuse its discretion in concluding Rose’s expert report did not represent a good-faith effort to meet the MLIIA’s requirements. See Wright, 79 S.W.3d at 53.
And, just as in Palacios, because the statutory 180-day time period had passed when the trial court here made that determination, section 13.01(e) required the court to dismiss with prejudice Rose’s claims against the hospital. See Palacios, 46 S.W.3d at 880 (citing Tex.Rev.Civ. Stat. ANN. art 4590i, § 13.01(e)). Consequently, the trial court did not abuse its discretion in dismissing Rose’s claims against the hospital. We resolve Rose’s issue against her.
We affirm the trial court’s order.
. Rose v. Garland Cmty. Hosp., 87 S.W.3d 188 (Tex.App.-Dallas 2002), rev’d, 156 S.W.3d 541 (Tex.2004).
. See Act of May 5, 1995, 74th Leg., R.S., ch. 140, § 1, 1995 Tex. Gen. Laws 985, 985-87. While this case was on appeal, the Legislature enacted House Bill 4 ("H.B.4”), which repealed article 4590i and governs all health care liability claims filed on or after September 1, 2003. See Garland Cmty. Hosp. v. Rose, 156 S.W.3d 541, 542 n. 2 (Tex.2004) (citing Act of June 2, 2003, 78th Leg., R.S., ch. 204, § 10.01, 2003 Tex. Gen. Laws 847, 884 (codified at Tex. Civ. Prac & Rem.Code Ann. §§ 74.001-.507 (Vernon 2005))). However, former article 4590i (designated herein as MLIIA) governs this case. Rose, 156 S.W.3d at 542 n. 2. Therefore, for purposes of simplicity, any citation to the former statute will be to Tex.Rev.Civ. Stat. Ann. art. 4590i, § 13.01.
. Technically, here, of course, there are "eight corners,” inasmuch as we have two separate affidavits, which, read together, constitute Rose’s expert report.