OPINION ON REMAND
TERRIE LIVINGSTON, Justice.
Appellant Wendy Collini, M.D. appeals the trial court’s denial of her motion to dismiss the health care liability claim of appellee Martha Pustejovsky. We originally dismissed this interlocutory appeal for want of jurisdiction. Collini v. Pustejovsky, 253 S.W.3d 292, 294 (Tex.App.-Fort Worth 2007), rev’d, 253 S.W.3d 216 (Tex. 2008). Because the Texas Supreme Court has held that we have jurisdiction, we now consider the appeal on the merits. Collini, 253 S.W.3d at 216. In one issue, appellant contends that the trial court abused its discretion in denying her motion to dismiss by concluding that the expert report served upon her satisfied the requirements of the civil practice and remedies code. See Tex. Civ. Prac. & Rem.Code Ann. § 74.351 (Vernon Supp.2008). We reverse and remand.
Background Facts
In June 2006, Martha Pustejovsky asserted a health care liability claim against Wendy Collini, M.D. Her original petition alleged that in 2002, another doctor prescribed Reglan to her and that Dr. Collini continued this prescription for three years. Pustejovsky claimed that the prolonged prescription and use of Reglan caused her to develop tardive dyskinesia.1 She asserted that Dr. Collini was negligent and grossly negligent because Dr. Collini failed to inform her of the known dangers associated with Reglan and failed to adequately [460]*460monitor the proper prescription of the drug and her condition while using it. Pustejovsky’s petition sought actual and punitive damages related to her alleged physical pain, suffering, and impairment along with further damages for mental anguish. In July 2006, Dr. Collini filed her original answer, generally denying Pustejovsky’s allegations.
In September 2006, in accordance with section 74.351, Pustejovsky served on Dr. Collini an expert report prepared by Paul Haberer, D.O. Dr. Haberer’s report indicates that he is a practicing physician, that he has been licensed in Texas since 1976, and that he has been board certified in family practice since 1989. It then recites that he has personal knowledge of the standard of care for primary care and family medicine physicians and that he has reviewed Pustejovsky’s medical records that he has acquired from various sources.
The report then alleges the following facts. A physician originally prescribed Reglan to Pustejovsky in 2002 to assist with abdominal and gastroesophageal issues, and Dr. Collini continued the prescription for almost three years. In December 2004, Pustejovsky began suffering from sleep disturbances and restlessness, and she also had tremors in her right hand.2 Dr. Collini ended the Reglan prescription in January 2005. As the Reglan left Pustejovsky’s system, the effects of its overuse were unmasked, and by the next month, she was diagnosed by Asher Imam, D.O. with “uncontrolled oral buccal dys-kinesia.” Over the next several months, two other doctors diagnosed Pustejovsky with tardive dyskinesia.
Dr. Haberer’s report then relates that because tardive dyskinesia is a known risk of taking Reglan, as has been disclosed by the drug’s manufacturer, the standard of care requires that a prescription for the drug must be limited to no more than twelve weeks and that those taking the drug should be closely monitored for symptoms of any moving disorder. The report also asserts that when Pustejov-sky’s hand tremors began, Dr. Collini should have tapered off Reglan, sought a substitute medication, and scheduled Pus-tejovsky for a neurological consultation.
Dr. Haberer also submitted his curriculum vitae with the report. The vitae indicates that Dr. Haberer is currently on an emergency room staff at a hospital in Eastland, Texas and that he has served in such a capacity at fourteen hospitals over the last thirty years. It further relates (among other things) that he received a bachelor’s degree in the field of pharmacy, that he attended a four-year pharmacy specialist course in the early 1960s while he was in the air force, and that he was an associate professor of medicine at the Texas College of Osteopathic Medicine from 1976 to 1988.
In October 2006, Dr. Collini filed a motion to dismiss Pustejovsky’s claim with prejudice, contending that she failed to make a good faith effort to serve an adequate expert report as required by section 74.351. Specifically, Dr. Collini argued that (1) Dr. Haberer did not qualify himself as an expert on liability and causation because his report failed to explain that he had any familiarity with prescribing Re-glan or any experience in assessing the causal relationship between Reglan and tardive dyskinesia and (2) Dr. Haberer’s report addressed causation only through conclusory statements.3 After Pustejov-[461]*461sky filed a response to Dr. Collini’s motion, Dr. Collini filed a reply. The reply incorporated Dr. Collini’s complete medical file on Pustejovsky, spanning more than seven hundred pages, in an attempt to discredit the factual information and resulting conclusions contained in Dr. Haberer’s report.
On December 18, 2006, the trial court held a hearing on Dr. Collini’s motion to dismiss. After Dr. Collini’s counsel briefly argued the motion, the trial court denied it. Dr. Collini timely perfected this interlocutory appeal.
The Sufficiency of Dr. Haberer’s Report
In her sole issue, Dr. Collini contends that the trial court abused its discretion by refusing to dismiss Pustejovsky’s claim because Dr. Haberer’s report fails to demonstrate his expert qualifications through experience with Reglan or the causal relationship between that drug and tardive dyskinesia and also fails to provide a specific factual explanation of such a causal relationship.
Texas courts agree that review of a trial court’s denial of a motion to dismiss under section 74.351 is subject to an abuse of discretion standard. See, e.g., Am. Transitional Care Ctrs. of Tex., Inc. v. Palacios, 46 S.W.3d 873, 875 (Tex.2001); San Jacinto Methodist Hosp. v. Bennett, 256 S.W.3d 806, 811 (Tex.App.-Houston [14th Dist.] 2008, no pet.); Moore v. Gatica, 269 S.W.3d 134, 139 (Tex.App.-Fort Worth 2008, pet. denied) (op. on remand). Also, a trial court’s decision on whether a physician is qualified to offer an expert opinion in a health care liability claim is reviewed under an abuse of discretion standard. Moore, 269 S.W.3d at 139.
To determine whether a trial court abused its discretion, we must decide whether the trial court acted without reference to any guiding rules or principles; in other words, we must decide whether the act was arbitrary or unreasonable. Downer v. Aquamarine Operators, Inc., 701 S.W.2d 238, 241-42 (Tex.1985), cert. denied, 476 U.S. 1159, 106 S.Ct. 2279, 90 L.Ed.2d 721 (1986). Merely because a trial court may decide a matter within its discretion in a different manner than an appellate court would in a similar circumstance does not demonstrate that an abuse of discretion has occurred. Id. A trial court does not abuse its discretion if it commits a mere error in judgment. See E.I. du Pont de Nemours & Co. v. Robinson, 923 S.W.2d 549, 558 (Tex.1995).
In a health care liability claim, a claimant must serve an expert report (that addresses liability and causation) on each defendant no later than the 120th day after the claim is filed. Tex. Civ. Prac. & Rem.Code Ann. § 74.351(a), (j). If an expert report has not been served on a defendant within the 120-day period, then on the motion of the affected defendant, the trial court must dismiss the claim with prejudice and award the defendant reasonable attorney’s fees and costs. Id. § 74.351(b).
A report “has not been served” under the statute when it has physically been served but it is found deficient by the trial court. Lewis v. Funderburk, 253 S.W.3d 204, 207-08 (Tex.2008). When no report has been served because the report that was served was found to be deficient, the trial court has discretion to grant one thirty-day extension to allow the claimant to cure the deficiency. Tex. Civ. Prac. & Rem.Code Ann. § 74.351(c). A report is deficient (therefore subjecting a claim to dismissal) when it “does not represent an [462]*462objective good faith effort to comply with the [statute’s] definition of an expert report.” Id. § 74.351(i); see Richburg v. Wolf, 48 S.W.3d 375, 377 (Tex.App.-Eastland 2001, pet. denied) (adding that it is the defendant’s burden to demonstrate that the good faith standard has not been satisfied). While the expert report “need not marshal all the plaintiffs proof,” it must provide a fair summary of the expert’s opinions as to the applicable standards of care, the manner in which the care rendered by the physician or health care provider failed to meet the standards, and the causal relationship between that failure and the injury, harm, or damages claimed. Tex. Civ. Prac. & Rem.Code Ann. § 74.351(r)(6); Palacios, 46 S.W.3d at 875, 878.
To qualify as a good faith effort, the report must “discuss the standard of care, breach, and causation with sufficient specificity to inform the defendant of the conduct the plaintiff has called into question and to provide a basis for the trial court to conclude that the claims have merit.” Palacios, 46 S.W.3d at 875. A report does not fulfill this requirement if it merely states the expert’s conclusions or if it omits any of the statutory requirements. Id. at 879. The information in the report “does not have to meet the same requirements as the evidence offered in a summary-judgment proceeding or at trial.” Id. When reviewing the adequacy of a report, the only information relevant to our inquiry is the information contained within the four corners of the document. Id. at 878; see Bowie Mem’l Hosp. v. Wright, 79 S.W.3d 48, 52 (Tex.2002).4 This requirement precludes a court from filling gaps in a report by drawing inferences or guessing as to what the expert likely meant or intended. See Austin Heart, P.A. v. Webb, 228 S.W.3d 276, 279 (Tex.App.-Austin 2007, no pet.) (citing Bowie Mem’l Hosp., 79 S.W.3d at 52).
An expert report concerning standards of care for physicians “authored by a person who is not qualified to testify ... cannot constitute an adequate report.” In re Windisch, 138 S.W.3d 507, 511 (Tex.App.-Amarillo 2004, no pet.); see Ehrlich v. Miles, 144 S.W.3d 620, 624-25 (Tex.App.-Fort Worth 2004, pet. denied). To be an “expert” on the departure from a physician’s standard of care (therefore qualifying the submission of an expert report), a person must be a physician who
(1) is practicing medicine at the time such testimony is given or was practicing medicine at the time the claim [463]*463arose;5
(2) has knowledge of accepted standards of medical care for the diagnosis, care, or treatment of the illness, injury, or condition involved in the claim; and
(3) is qualified on the basis of training or experience to offer an expert opinion regarding those accepted standards of medical care.
Tex. Civ. Prac. & Rem.Code Ann. § 74.351(5)(A), § 74.401(a) (Vernon 2005). In determining the third element of this standard, courts must consider whether the physician who completed the report (1) is board certified or has other substantial training or experience in an area of medical practice relevant to the claim and (2) is actively practicing medicine in rendering medical care services relevant to the claim. Id. § 74.401(c). In other words,
there is no validity, if there ever was, to the notion that every licensed medical doctor should be automatically qualified to testify as an expert on every medical question.... [T]he proponent of the testimony has the burden to show that the expert possesses special knowledge as to the very matter on which he proposes to give an opinion.
Ehrlich, 144 S.W.3d at 625 (quoting Broders v. Heise, 924 S.W.2d 148, 152-53 (Tex.1996)). For this reason, the offered report must generally demonstrate that the expert has “knowledge, skill, experience, training, or education regarding the specific issue before the court which would qualify the expert to give an opinion on that particular subject.” Id. (quoting Roberts v. Williamson, 111 S.W.3d 113, 121 (Tex.2003)).
However, there are certain standards of medical care that apply to multi-pie schools of practice and any medical doctor. See McKowen v. Ragston, 263 S.W.3d 157, 165 (Tex.App.-Houston [1st Dist.] 2007, no pet.); Blan v. Ali, 7 S.W.3d 741, 745-46 (Tex.App.-Houston [14th Dist.] 1999, no pet.). Therefore, a physician “who is not of the same school of medicine [as the defendant] is competent [to submit a report] if he has practical knowledge of what is usually and customarily done by a practitioner under circumstances similar to those confronting the defendant.” Ehrlich, 144 S.W.3d at 625; see Marling v. Maillard, 826 S.W.2d 735, 740 (Tex.App.Houston [14th Dist.] 1992, no writ).
Dr. Haberer’s Expert Qualifications
Dr. Collini contends that Dr. Ha-berer failed to qualify himself as an expert because his report does not demonstrate any expertise or experience in prescribing Reglan or diagnosing or treating drug-induced tardive dyskinesia. Pustejovsky asserts that Dr. Haberer was not required to address his experience with Reglan or tardive dyskinesia because the specific issue in this case concerns a physician’s duty to comply with a drug manufacturer’s expressed instructions and warnings, which is a common standard known by all physicians.
Was Dr. Haberer’s Report Required to Demonstrate His Knowledge of and Experience Related to the Accepted Standards of Medical Care Specifically Concerning the Prescription of Reglan?
Dr. Collini first contends that because Dr. Haberer’s current area of practice is emergency medicine, he cannot address [464]*464the standard of care that applies to her, because she is an internist. However, the proper inquiry in assessing Dr. Haberer’s qualifications to submit an expert report is not his area of practice, but his familiarity with the issues involved in the claim before the court. See Blan, 7 S.W.3d at 745.
Next, Dr. Collini asserts that Dr. Haber-er’s report is insufficient to establish his qualifications because it does not establish that he has any specific experience “regarding the prescription of Reglan.” To establish his qualifications, Dr. Haberer was required to demonstrate experience with the specific issues raised by Pustejov-sky’s claim. See Ehrlich, 144 S.W.3d at 625.
Pustejovsky’s original petition indicated that the specific factual issue she was raising in her claim concerned the lengthy, ongoing prescription of Reglan. Dr. Ha-berer’s report describes that
[t]he standard of care pertaining to Re-glan is to limit the time prescribed to no more than 12 weeks and the lowest dose needed to provide therapeutic relief. For gastrointestinal problems, Reglan’s manufacturer specifies that this drug should be prescribed for no more than 4-12 weeks and this is the standard of care applicable to this case. Tardive dyskinesia (TD) is a known complication of metoclopramide, which is also disclosed by Reglan’s manufacturer.
There are minimum, general standards of prescribing medication that are common to all physicians and all schools of practice. See Patel v. Williams ex rel. Estate of Mitchell, 237 S.W.3d 901, 905 (Tex.App.-Houston [14th Dist.] 2007, no pet.) (approving of an expert report’s explanation of the breach of the standard of care, for prescribing Risperdal because its use for treating dementia had not been approved by the FDA and concluding that a “reasonable physician should not, as a general proposition, prescribe the wrong drug for his patients”); Puempel v. Lopez, No. 05-07-00371-CV, 2007 WL 3173405, at *3-4 (Tex.App.-Dallas Oct.31, 2007, no pet.) (mem. op.) (affirming the use of FDA and PDR guidelines to define the standard of care for prescribing weight loss medication); Metot v. Danielson, 780 S.W.2d 283, 286-87 (Tex.App.-Tyler 1989, writ denied), overruled on other grounds by Cecil v. Smith, 790 S.W.2d 709, 716 (Tex.App.-Tyler 1990) (op. on reh’g), rev’d, 804 S.W.2d 509 (Tex.1991) (holding that the trial court abused its discretion when it decided that a board-certified doctor was not qualified to testify about a neurosurgeon’s “general minimum standards” for the prescription of drugs that are “applicable to all physicians”). Dr. Haberer’s report indicates that he certainly has experience with the general standards related to prescribing medications. For instance, it demonstrates that he is board certified in family practice, that he has “personal knowledge of the standard of care applicable to ... family medicine,” that he has experience in practicing in hospitals and in family practice, and that, as explained above, his undergraduate degree and postgraduate employment and research activities concerned pharmaceutical matters.
Based on this experience, his report demonstrates his qualifications to opine on the duties to follow a manufacturer’s instructions about the length of time a drug should be prescribed, heed warnings specifically given by the manufacturer related to that drug, and monitor a patient’s conditions that may be connected to those warnings. Because Dr. Haberer’s report indicates that he had knowledge of the accepted standards of medical care related to prescribing medication and acting on such medication’s related instructions and warnings and that he has experience and training in doing so, we conclude that he [465]*465was qualified to submit a report establishing Dr. Collini’s standards of care in this case.6 See Tex. Civ. Prac. & Rem.Code Ann. § 74.401(a)(2), (8).
Was Dr. Haberer’s Report Required to Demonstrate His Knowledge of and Experience Related to the Causal Relationship of Reglan with Tar-dive Dyskinesia?
Next, Dr. Collini asserts that Dr. Haberer has not qualified himself as an expert on causation because he has not recited experience or expertise in the diagnosis and treatment of drug-induced tar-dive dyskinesia. Along with the standards of care and a description of a physician’s inability to satisfy those standards, an expert report served under section 74.351 must address the causal relationship to the damages the plaintiff has claimed. Id. § 74.351(j), (r)(6). A physician is qualified to submit an expert report on the causal relationship between a departure from a standard of care and an injury when he would otherwise be qualified to address causation under rule 702 of the Texas rules of evidence. Id. § 74.851(r)(5)(C); see Tex.R. Evid. 702;7 Thomas v. Alford, 230 5.W.3d 853, 857 (Tex.App.-Houston [14th Dist.] 2007, no pet.). The party offering the witness as an expert on causation must establish that the witness is qualified to testify under rule 702. Mem’l Hermann Healthcare Sys. v. Burrell, 230 S.W.3d 755, 762-63 (Tex.App.-Houston [14th Dist.] 2007, no pet.) (deciding that a doctor was qualified to opine about causation because his report demonstrated direct experience with treating decubitus ulcers, which was the condition at issue). To be so qualified, “an expert must have knowledge, skill, experience, training, or education regarding the specific issue before the court that would qualify the expert to give an opinion on that particular subject.” Thomas, 230 S.W.3d at 857, 860 (citing Broders, 924 S.W.2d at 153) (holding that because the doctor who submitted an expert report did not demonstrate knowledge of cancer treatment, he was not qualified to offer an opinion that an earlier diagnosis could have produced a better outcome for the plaintiff). Further, to justify the submission of an opinion under the rules of evidence, the proponent of the opinion must show that the opinion is reliable. See Mack Trucks, Inc. v. Tamez, 206 S.W.3d 572, 578 (Tex.2006).
While Dr. Haberer’s curriculum vitae does establish a background in pharmaceutical matters, his report does not indicate that he has any specific knowledge, experience, education, or training in assessing the causal relationship between the prolonged use of Reglan and tardive dyskine-sia.
In fact, his report does not state that he has any experience or training regarding [466]*466Reglan or tardive dyskinesia at all; rather, it only generally states that he has knowledge applicable to “primary care and family medicine.” The report does not indicate that the diagnosis of tardive dyskinesia resulting from prolonged Reglan use is a matter that is developed in various fields to the extent that any physician would be qualified to report about it. Dr. Haberer, therefore, has not demonstrated his qualifications, under the standards set forth above, to support his attempt to causally link the alleged breach of Dr. Collini’s duty to follow manufacturer’s instructions and warnings to Pustejovsky’s deteriorating condition starting in December 2004.
Pustejovsky contends that Dr. Haberer’s qualifications to assess causation may be established by the facts that Reglan’s manufacturer disclosed tardive dyskinesia as a known complication and that the report details that three physicians diagnosed her with dyskinesia related to her Reglan use. Courts have held that in addressing causation, a reporting physician may rely on the opinions of other individuals who have rendered reports or diagnoses. See Kelly v. Rendon, 255 S.W.3d 665, 676 (Tex.App.Houston [14th Dist.] 2008, no pet.) (noting that “nothing in the health care liability statute prohibits an otherwise qualified physician from relying on [another opinion] in the formation of the physician’s own opinion”); Cresthaven Nursing Residence v. Freeman, 134 S.W.3d 214, 234 (Tex.App.-Amarillo 2003, no pet.) (holding that a testifying physician properly relied, in part, on the opinions of other doctors in establishing causation); see also Tex.R. Evid. 703 (stating that an expert can base an opinion on reasonably reliable data). However, in both Kelly and Freeman, the reporting physicians also demonstrated their own qualifications related to their specific experience with conditions involved in those claims. See Kelly, 255 S.W.3d at 673-75; Freeman, 134 S.W.3d at 232. Also, while Dr. Haberer’s report briefly states the conclusions of the three physicians who examined Pustejovsky, it does not provide any background on the experience or training of those physicians that would signal to the trial court that those opinions were reliable. See Tex.R. Evid. 703 (requiring reasonable reliance in the formation of an expert opinion); Gammill v. Jack Williams Chevrolet, Inc., 972 S.W.2d 713, 728 (Tex.1998) (noting that a trial court must determine whether the analysis used to reach an expert’s conclusions is reliable).
Finally, Dr. Haberer’s report contains several statements regarding Reglan or tardive dyskinesia that are unrelated to either the other physicians’ opinions or the manufacturer’s instructions and warnings. For instance, Dr. Haberer states that Re-glan can “help mask the symptoms of dys-kinesia” and that the “risk of [tardive dys-kinesia] is greater in women, the elderly,8 and increases with duration of use.” As demonstrated, while Dr. Haberer may be well qualified to make these assertions, the four corners of his report simply do not provide any details regarding such qualifications.
We hold that Dr. Haberer has not adequately demonstrated his qualifications to submit an expert report on the issue of causation; therefore, his report is deficient and does not comply with section 74.351. See Tex. Civ. Prac. & Rem.Code Ann. § 74.351(0, (r)(5)-(6); Palacios, 46 S.W.3d at 877; Windisch, 138 S.W.3d at 511 (noting that a report authored by an unqualified doctor cannot be adequate). Therefore, Dr. Haberer’s report is insufficient; we sustain Dr. Collini’s sole issue. We now turn to the issue of causation to pro[467]*467vide the trial court with guidance on the retrial of this issue should the trial court grant Pustejovsky an extension. See Edinburg Hosp. Auth. v. Trevino, 941 S.W.2d 76, 81 (Tex.1997).
The Adequacy of Dr. Haberer’s Causation Explanation
Finally, Dr. Collini asserts that apart from the issues regarding qualifications, Dr. Haberer’s report contains an insufficient explanation of the causal relationship between Dr. Collini’s prescriptions of Reglan and Pustejovsky’s conditions. As we have described, an expert report must provide a fair summary of the expert’s opinions on the causal relationship of a breach from a standard of care to the harm claimed in the case, with enough specificity to allow the trial court to conclude that the plaintiffs claims have merit. Palacios, 46 S.W.3d at 875, 878; see Tex. Civ. Prac. & Rem.Code Ann. § 74.351(r)(6). Applying this standard, an expert report is insufficient when it contains only a series of repetitious, concluso-ry statements regarding causation. See Jones v. King, 255 S.W.3d 156, 159 (Tex.App.-San Antonio 2008, pet. denied) (mem. op.) (adding that an expert must “explain the basis of his statements to link his conclusions to the facts”).
We hold that Dr. Haberer’s report addresses causation in a conclusory fashion and is therefore insufficient. While the report adequately describes Pustejovsky’s alleged physical harm (including her sleep disturbances, hand tremors, and leg restlessness) and states the conclusions of four doctors (including Dr. Haberer)9 that such harm was related to Reglan use, it does not provide any medical detail as to how the Reglan caused Pustejov-sky’s conditions or, more importantly, how Dr. Collini’s specific prescriptions of Reglan (beyond the taking of Reglan generally) attributed to the harm.10 And while the manufacturer’s warning (that Reglan should not be prescribed for more than twelve weeks) coupled with the causation opinions of the four doctors (though conclusory) may create a reasonable inference that Dr. Collini’s prolonged prescription of Reglan caused Pustejov-sky’s condition, we are not permitted to rely on that inference in reviewing Dr. Haberer’s report.11 See Webb, 228 S.W.3d at 279 (noting that courts are precluded “from filling gaps in a report by drawing inferences”); see also Castillo v. August, 248 S.W.3d 874, 883 (Tex.App.-El Paso 2008, no pet.) (explaining that courts are not permitted to infer causation). Because Dr. Haberer’s report does not ade[468]*468quately address the link between Dr. Col-lini’s alleged breach of her standard of care and Pustejovsky’s tardive dyskinesia that allegedly resulted, the report is insufficient.
Proper Disposition Following Reversal
In her brief, Dr. Collini contends that upon reversal, we should render a judgment dismissing Pustejovsky’s claims with prejudice. Pustejovsky asserts that if we hold Dr. Haberer’s report to be insufficient, we should remand this case to the trial court to allow it to consider granting thirty additional days to cure the deficiency.12
The Texas Supreme Court has held that section “74.351’s plain language permits one thirty-day extension when the court of appeals finds deficient a report that the trial court considered adequate.” Leland v. Brandal, 257 S.W.3d 204, 207 (Tex.2008). Accordingly, the trial court should have an opportunity to consider granting Pustejovsky an extension to cure the deficiencies detailed in this opinion.
Conclusion
Having sustained Dr. Collini’s only issue, we reverse the trial court’s decision regarding the sufficiency of Dr. Haberer’s report and remand this case to that court to consider the issue of whether to grant Pustejovsky a thirty-day extension to file an adequate expert report.
DAUPHINOT, J., filed a dissenting and concurring opinion.