with whom WATT, C.J., and COLBERT, J., join, concurring.
¶ 1 The court reverses today a summary judgment for the defendants, declares a *212nurse’s affidavit does provide an evidentiary substitute with an acceptable expert opinion on the etiology of decubitus ulcers, and remands the cause for trial of disputed fact issues.
¶2 Although I concur in the court’s pronouncement, I write separately to articulate some of the reasons that impel me to the court’s view.
I
THE ROOTS OF A REGISTERED NURSE’S EXPERTISE IN THE ETIOLOGY OF DECUBITUS ULCERS
A.
Training, Education and Experience
¶ 3 A registered nurse may be qualified by education, training and experience to give expert opinion testimony on the etiology of decubitus ulcers.1 Nothing in the evidentia-ry materials impels a conclusion to the contrary. This is so because the nurse’s affidavit in the summary record shows in concrete terms that by training, education and experience she was familiar with the plaintiffs injury and its causation.2
B
Nursing Standards of Care Are Private Standards That Encapsulate Medical Etiology
¶ 4 The nurse’s affidavit invokes and incorporates private professional standards of nursing care3 which confirm an etiological link between substandard patient positioning and the development of decubitus ulcers. The etiology which she relies on — a causative link of decubitus ulcers to substandard pa*213tient positioning — is built into the nursing care standards for prevention of bedsores.4 Although the nurse doubtless possesses skill, knowledge, experience and training related to her field (or speciality), the fundamental support provided for her expertise, which is revealed in the affidavit of record, is to be found in the nursing care standards.5 The nurse did not independently establish a causal link between the appearance of bedsores and the malpositioning of the patient by drawing her own conclusion solely from her personal knowledge of the skin’s reaction to external forces in action.
c.
Overlapping Expertise Drawn From Different Health Care Fields
¶ 5 Legally recognized expertise in a scientific subject need not be confined to a single academic discipline or a single learned profession. It may be found in several areas of learning or in several practising professions whose scientific insight overlaps with that of another field of knowledge.6 If so, persons of different occupations or academic areas of knowledge may qualify as experts in the same subject. This is certainly true in this case.
*214¶ 6 Both physicians and registered nurses may qualify by education, training and experience to give expert testimony about the etiology of decubitus ulcers. No scientific or academic field of knowledge can be said to be tightly compartmentalized within a single profession.
D.
The Medical Expertise In The Etiology Of Decubitus Ulcers
¶ 7 While health care experts consist of both medical and nursing professionals, the expertise required of the two fields is often very different. The nursing professional’s expertise utilized in this case is centered on the positioning technique’s role in avoiding development of decubitus ulcers. Although the nurse doubtless based the causation opinion in the evidentiary materials on her own experience, education and training,7 added strength must be accorded to her expert view on the etiology by her reliance upon the unchallenged professional standards in which the needed causal link is comprised.
II
THE NISI PRIUS CHALLENGE TO THE NURSE’S QUALIFICATIONS
¶ 8 The trial court rejected sua sponte the nurse’s qualification as an expert witness for causation testimony based solely on the credentials she submitted with the evidentiary materials in the record. Its challenge to the witness’ expertise was interposed in the exercise of the trial court’s judicial powers to dispose of summary process.8 When considering summary relief nisi prius courts are empowered to resolve all legal issues necessary for the decision that will dispose of a summary judgment quest.9
¶ 9 To assist the trial court in analyzing the nursing care standards or a nurse’s qualifications as an expert witness, briefs that accept or challenge the basis for one’s expert status would have been most helpful. The parties offered here no assistance to the trial court in the resolution of the legal issues tendered by summary process. The defendants never challenged the nurse’s qualifications to give expert causation testimony. Neither did they suggest that the nursing standards, relied on in the evidentiary materials, were incorrectly applied or are flawed because they fail to conform to the *215currently accepted teachings of medicine.10 The plaintiff also raised no challenge to the physician’s expert opinion about decubitus ulcers’ development.
¶ 10 The registered nurse’s evidentiary materials did not facially disqualify her from giving an expert opinion on the etiology of the plaintiffs ulcers. Her expertise is partly rested on full support from the unchallenged standards that comprise the medical view of decubitus ulcers’ etiology. Had any party challenged at nisi prius either the experts’ qualifications or the utilized nursing standards and offered additional materials of their own (by acceptable probative substitutes), the outcome of today’s legal analysis might have been different.
Ill
SUMMARY
¶ 11 The etiology of decubitus ulcers may lie within the professional expertise of a registered nurse as well as of a physician. Members of both professions could hence qualify by education, professional practice and experience to give expert testimony on that subject.
¶ 12 No profession will be permitted to monopolize the expertise in any field of scientific knowledge if another is shown to possess like or equal insight into the matter that lies under judicial inquiry.11
¶ 13 There was here neither a challenge to the registered nurse’s qualifications nor to the professional standards she invoked. The materials submitted in summary process did not facially disqualify her as an expert. She was amply supported by the unchallenged standards of her profession.
¶ 14 Because the etiological link between the nurses’ malpositioning of plaintiff and his development of decubitus ulcers stands in dispute by submission of two expert opinions that contradict one another, both tendered by acceptable evidentiary substitutes, I concur in today’s reversal.
. See, e.g., Mellies v. National Heritage, Inc., 6 Kan.App.2d 910, 636 P.2d 215, 222-23 (1981); State v. Bermisa, 104 Hawai'i 387, 90 P.3d 1256, 1264-65 (App.2004).
. The nurse’s affidavit states in pertinent part:
"... I have a degree in nursing which I obtained from Cameron University in Lawton, Oklahoma in 1982. My license is in good standing in the State of Oklahoma. I am certified in wound care. I am familiar with the standard of care for providing nursing care to critically ill and or bedridden patients. I currently practice in the field of nursing, providing care to patients in the Intensive Care Unit at Southwestern Medical Center in Lawton, Oklahoma....”
. The nurse's affidavit states in pertinent part:
"... The standard of care for a critically ill patient such as Stephen Gaines is that the patient must be turned and or repositioned every two hours. This was not done by the nurses at Comanche County Memorial Hospital assigned to care for Stephen Gaines ... Additionally, the standard of care was not met by the nurses ... because they did not place heel protectors on Stephen Gaines. The failure to place the heel protectors was a direct and foreseeable consequence and cause of the development of decubitus ulcers on Stephens Gaines's feet and heels.... As a direct result of the failure of the nurses ... to meet the standard of care, Stephen Gaines developed severe decubitus ulcers on his coccyx, heels and possibly head region...."
(emphasis added).
Private standards are those promulgated by a profession or industry. Private standards-making organizations, which have no mandatory powers, establish standards by "general consent” of industry or trade. Marian P. Opala, The Anatomy Of Private Standards-Making Process: The Operating Procedures Of The USA Standards Institute, 22 Okl.L.Rev. 45, 46 (1969). In Frank J. Cavico and Nancy M. Cavico, The Nursing Profession In The 1990’s: Negligence And Malpractice Liability, 43 Clev. St. L.Rev. 557 (1995)(footnotes omitted), the authors note:
Private entities can also establish and define the nursing standards of care. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO), a private nongovernmental agency that establishes standards for the operation of hospitals, has promulgated A Guide to JCAHO Nursing Services Standards to govern nurses at JCAHO hospitals or facilities. These guidelines provide evidence of the appropriate standard of care even at facilities which are not accredited by JCAHO.
Nursing organizations such as the American Nurses Association (hereinafter ANA), and various specialty organizations such as the Emergency Nurses Association (hereinafter ENA), promulgate their own rules of conduct which serve as guidelines for acceptable nursing practice. The ANA's standards are generally applicable to nurses in all settings, whereas each of the ANA’s divisions, such as medical-surgical, maternal-child, geriatrics, and mental health, have established their own distinct specialty standards. Nursing Codes of Ethics, such as those produced by the ANA, ENA, and individual hospitals, also contain standards of care which are applicable to nurses practicing in the profession.
. See in this connection Smith v. Kris-Bal Realty, Inc., 242 N.J.Super. 346, 576 A.2d 934, 935 (1990) (the court held that an Occupational Safety and Health Act code, when used in connection with expert testimony, may be relied upon to illustrate industry standards and to provide support for the opinion of an expert on the proper standard of care under the teachings of McComish v. DeSoi, 42 N.J. 274, 200 A.2d 116, 120-21 (1964)).
. While private standards promulgated by standards-making organizations have no official or legal status except to govern the conduct of the profession and industry, courts generally admit them unless a challenge is sustained. The Anatomy of Private Standards-Making Process, supra note 3, at 63-66.
. Fabianke v. Weaver By and Through Weaver, 527 So.2d 1253, 1258 (Ala.1988) (routine prenatal, labor, and delivery treatment is an area of overlapping expertise of the family and OB/GYN medical specialties); Sinkfield v. Oh, 229 Ga. App. 883, 495 S.E.2d 94 (1997)(pharmacoIogy and toxicology are overlapping fields of science and medicine); Stubbs v. Ray, 218 Ga.App. 420, 421, 461 S.E.2d 906 (1995) (a board-certified general surgeon shared overlapping expertise with defendant radiologist); Steele v. Buxton 93 Ohio App.3d 717, 639 N.E.2d 861 (1994) (a general practitioner serving as a surgical assistant was competent to testify because of overlapping specialties); Marshall v. Yale Podiatry Group, 5 Conn.App. 5, 496 A.2d 529, 531 (1985) ("where the evidence indicates that the specialties overlap and the applicable standard of care is common to each, a medical expert from either of the overlapping groups who is familiar with that common standard is competent to testify as to the standard of care”)(emphasis added). In Enslen v. Kennedy, 26 Cal.Rptr.3d 274, 127 Cal.App.4th 1448, 1458 (2005) the court noted that the "state’s jurisprudence of 'cross-over' expert testimony has been one long march toward allowing experts in one profession to testify as to the malpractice of practitioners in a related profession or discipline when there is commonality or ‘overlap’ ... [in] the two professions and the malpractice claim implicates that commonality or overlap." (emphasis added). In Sinkfield, supra, a statement in concurrence noted that "[i]f an expert in the area of health sciences, which overlaps in another area of health sciences, can qualify as an expert witness to testify as to the standard of care exercised in the area of overlapping treatment, then it also follows that such expert can testify as to his or her opinion as to causation, etiology, even though the expert is not a holder of a medical degree." 495 S.E.2d at 99 (Eldridge, Judge, concurring)(emphasis added). See also Rosenberg by Rosenberg v. Cahill, 99 N.J. 318, 492 A.2d 371, 379 (1985)(a licensed medical doctor may be competent to express an opinion concerning the standard of care applicable to a chiropractor as to matters that each of these licensed disciplines shares in common in terms of education, training and licensure); Alexander v. Mount Carmel Med. Ctr., 56 Ohio St.2d 155, 383 N.E.2d 564 (1978) (a podiatrist is competent to testify against an orthopedic surgeon on the issue of proper casting of a fracture); Mitchell v. United States, 141 F.3d 8, 15-16 (1st Cir.1998) (an internist who had performed over 20,-000 colonoscopies may testify to the standard of care expected of gastroenterologists in adjusting anticoagulant levels for patients undergoing colo-noscopies); Handson v. HCA Health Svcs. of Ga., Inc., 264 Ga. 293, 294, 443 S.E.2d 831 (1994) (an allopathic physician is competent to testify as to an osteopathic physician’s care and skill); Crook v. Funk, 214 Ga.App. 213, 215, 447 S.E.2d 60 (1994) (a physician is competent to testify about competency of registered nurse); Soteropulos v. Schmidt, 556 So.2d 276, 280 (La.App.1990) (orthopedic surgeons were qualified to give their expert opinions regarding a vascular surgeon’s adherence to standard of care in performing a below-knee amputation). See Expert Evidence; A Practitioner's Guide to Law, Science, and the FJC Manual (Bert Black, Patrick W. Lee, eds.)(1997)(App., Federal Judicial Center, Reference Manual on Scientific Evidence, Evidentiary Framework, at 55-67).
. See, e.g., Mellies v. National Heritage, Inc., supra note 1 at 222-23.
. According to the trial court's summary judgment:
The Court, after reading the briefs of the parties, hearing argument of counsel and being fully advised in the premises finds:
1. That there is no issue of material fact in dispute.
2. That plaintiff has not endorsed a competently trained medical professional who is experienced and licensed to make a medical diagnoses, by endorsing a nurse expert rather than a physician.
3. That plaintiff, therefore, has failed to produce any competent and admissible evidence regarding the element of causation.
(emphasis added).
The trial court’s summary judgment is not responsive to the issues in the case. (1) The focus in summary process is on whether the tendered proof by evidentiary materials in the record reveals only undisputed material facts supporting but a single inference that favors the movant's quest for relief. (2) The nonmovant is not held to the standard of producing forensic evidence. Davis v. Leitner, 1989 OK 146, ¶ 13, 782 P.2d 924, 926 ("The [evidentiary] materials attached to a response to a motion for summary judgment are not to be held to the standard of competent, admissible evidence.”). All that is required of the nonmovant is to “present something which shows that when the date of trial arrives, he will have some proof to support his allegations.” Id. For an item of evidentiary material to be insufficient to defeat a motion for summary judgment, it must either facially lack probative value or be incapable of conversion at trial to admissible evidence. Copeland v. Lodge Enterprises, Inc., 2000 OK 36, 19, 4 P.3d 695, 699; Seitsinger v. Dockum Pontiac Inc., 1995 OK 29, ¶ 16, 894 P.2d 1077, 1081.
.Although in the course of summary process trial judges may consider sua sponte and decide legal issues (Travelers Ins. Co. v. L.V. French Truck Service, Inc., 1988 OK 76, ¶ 13, 770 P.2d 551, 557), the better practice for judges to employ when the issue is one of first impression is to call for and receive help through briefs. The trial judge in this case would have been aided by briefs since the issue whether the nurse's credentials qualified her as an expert witness for giving causal-link testimony is presently unsettled by Oklahoma jurisprudence.
. If the invoked nursing standards are in conflict with other professional standards on the subject or are incorrectly rendered by the nurse's affidavit, they can be challenged in both sum-maiy and trial process. Because the nursing care standards noted in the nurse’s affidavit were not challenged at nisi prius, the court must accept them here without question. See generally matters of health care upon which a qualified nurse may give helpful expert testimony. Robert C. Clifford, qualifying and attacking expert witnesses §532, at 5-52 (rev. 18, 2005)(1988).
. If one party’s expert witness' highest university degree attained is of a lower rung in the academic hierarchy than that of another party's expert, but their level of gained knowledge in the field, by learning or experience, is sufficient to qualify both as forensic experts, their standing is the same. Neither is to be deemed superior to the other. Both stand on equal footing. It is the trier of fact who must then decide which of their divergent opinions is to be believed and which is to be rejected as unworthy of acceptance. This is the quintessence of the common-law system’s technique for ascertaining the truth in the conduct of a trial. Giles v. Rhodes, 171 F.Supp.2d 220, 227 (S.D.N.Y.,2001) ("That reality reflects the jury’s traditional power to accept or reject the testimony of any witness, lay or expert.”).