Pursuant to Rule 21.1 of the Colorado Appellate Rules, the United States Court of Appeals for the Tenth Circuit has certified the following three questions of Colorado law which may be determinative of an appeal presently pending in that court:
1. Under the 1977 amendments to the Colorado medical negligence statute of limitations, Section 13-80-105, [6] C.R.S. [1985 Supp.], is this action barred where brought by a ... mentally incompetent person [who was fifteen years old in 1977]1 and on his behalf by co-guardians, alleging negligence by medical practitioners and a hospital in July and August 1962, which action was not commenced *1080within one year after the effective date of the said 1977 amendments to the medical negligence statute of limitations?
2. Was the running of the medical negligence statute of limitations, Section 13-80-105, [6] C.R.S. [1985 Supp.], tolled in this case, thereby rendering plaintiffs’ action timely on the theory that mental incompetence caused by defendants’ negligent conduct tolled the statute of limitations for an action based on that conduct?
3. Did the third clause of the [first] sentence of subsection [2]2 of the medical negligence statute of limitations, Section 13-80-105, [6] C.R.S. [1985 Supp.], which provides that “if there is a discovered act or omission which could give rise to an action, the limitations period shall not run unless a guardian ad litem is appointed to represent the minor child,” toll the running of the medical negligence statute of limitations in this case until the appointment of Steven Clyde Tenney's parents as his co-guardians, thereby rendering plaintiffs’ action timely?
We agreed to respond to the certified questions and now answer question one in the negative, and question two in the affirmative. Our answers to these questions render it unnecessary to respond to question three.
I.
The plaintiffs-appellants, Clyde Arthur Tenney and Ardith Mae Tenney, are the parents of Steven Clyde Tenney, who was bom on August 10, 1962, at Mercy Medical Center in Denver, Colorado. Steven’s parents were appointed his legal co-guardians on September 8, 1980. On August 10, 1982, Steven’s parents, as co-guardians on behalf of Steven, filed a diversity action in the United States District Court for the District of Colorado. Alleging that the plaintiffs were citizens and residents of the state of Washington and that the defendants were citizens and residents of the state of Colorado, the complaint sought money damages against the defendants-ap-pellees, Carl Flaxer, Eugene Schulman, Frank S. Potestio, and Mercy Medical Center, for injuries caused to Steven as the result of the defendants’ negligence in connection with the treatment administered to Steven’s mother during the late stages of her pregnancy in July and August 1962 and during Steven’s birth on August 10, 1962. The complaint alleged that as a direct and proximate result of the negligence of the individual defendants Steven was born with severe and permanent brain damage and has suffered total and permanent disability since birth.
The district court granted the defendants’ motions for summary judgment, ruling that the action was barred by the Colorado medical malpractice statute of limitations, § 13-80-105, 6 C.R.S. (1985 Supp.). The plaintiff appealed to the United States Court of Appeals for the Tenth Circuit, which thereafter certified the three questions to this court.
II.
A.
Section 13-80-105, 6 C.R.S. (1985 Supp.), the version of the medical malpractice statute of limitations under which we decide the questions before us, was enacted in the form herein discussed in 1977.3 Under sec*1081tion 13-80-105(1), a claim for medical malpractice in Colorado must be filed within two years “after the person bringing the action discovered, or in the exercise of reasonable diligence and concern should have discovered, the injury.” The statute also contains a repose provision which, subject to specified exceptions, states that “[i]n no event may such action be instituted more than three years after the act or omission which gave rise” to the injury. § 13-80-105(1). The three-year repose provision does not apply in cases of knowing concealment of the act or omission, or of leaving an unauthorized foreign object in the body, or in the case of a minor who was under six years old at the time of injury. § 13-80-105(1)(a), (b). In the case of an injury to a child under six, an action may be brought on his behalf within two years of his sixth birthday. § 13-80-105(1)(b).
In addition to the above exceptions to the repose provision, section 13-80-105(2) provides for the tolling of the periods of limitation and repose in the case of a minor under eighteen who has no natural or legal guardian; such a claim must be filed within two years after a legal guardian has been appointed, or within two years after the minor reaches eighteen, whichever first occurs. Section 13-80-105(3) states that for purposes of the limitation and repose periods of the statute a person under disability includes a “mental incompetent.”4
*1082Before 1977 a minor entitled to bring an action for medical malpractice had until two years after he reached the age of majority to file his claim. See § 13-80-116, 6 C.R.S. (1973). Since Steven was only fifteen years of age in 1977, his claim was still viable under the pre-1977 statutory scheme. In 1977 the General Assembly amended the medical malpractice statute by including, among other revisions, a special section which stated that all causes of action existing on the effective date of the statute, July 1, 1977, would not be barred until one year after that date, or until the expiration of the limitations period, whichever was longer. See ch. 198, sec. 5, 1977 Colo.Sess.Laws 816, 818.
B.
The United States District Court interpreted section 13-80-105(l)(b), 6 C.R.S. (1985 Supp.), which states that any claim on behalf of a minor under six years on the date of the act or omission must be filed within two years after the minor reaches six years of age, as applicable to any claim on behalf of a minor who had either a natural or legal guardian irrespective of the existence of any other disability, such as mental incompetency. It was the district court’s view that:
[Wjhether a minor under six years of age has a disability or doesn’t have a disability ... simply does not make any difference because the statute very clearly says if the action is brought by or on behalf of a minor who is under six years of age on the date of occurrence of the act or omission for which the action is brought, then such action may be instituted within two years after said minor reaches six years of age_ The natural or legal guardian has the obligation to bring the action within two years of the minor reaching six years of age, or because of the change in the statutory language, one year after July 1, 1977.
Because in the present case the action was not filed by Steven’s parents before Steven’s eighth birthday or within one year of July 1, 1977, the district court concluded that his claim was barred.
The district court’s resolution of the matter, however, does not take into account that Steven, in addition to having been a minor one year after July 1, 1977, was at all times since his birth a mental incompetent. If mental incompetency, not minority, is viewed as Steven’s disability for the purposes of the statute of limitations, then Steven’s claim was not time-barred. While section 13-80-105(3), 6 C.R.S. (1985 Supp.), includes a mental incompetent within the definition of a person under disability, it does not specifically address the effect of such incompetency on the limitation and repose periods applicable to medical malpractice claims. Section 13-81-103(l)(a), 6 C.R.S. (1973), does address this question,5 *1083and, as we recently held in Southard v. Miles, 714 P.2d 891 (Colo.1986), this section establishes an indefinite toll for a “person under a disability” by reason of mental incompetency.6
In Southard, suit had been brought against three physicians and a hospital by the parents of a twenty-five-year-old man who had sustained irreversible brain damage, allegedly as a result of the defendants’ negligence. Since the action was filed over three years after the date of the injury, the defendants argued that the claim was barred under section 13-80-105. We disagreed, concluding that if plaintiff Southard were found on remand to be under a disability sufficient to invoke the general tolling provisions of section 13-81-103(1)(a), his claim would not be barred, since that provision also applied to the limitations period for medical malpractice claims:
[Section 13-81-103] is intended to apply to any statute of limitations in this state, § 13-81-101(1), 6 C.R.S. (1973), unless there exists a special statute pertinent to the claim that conflicts with the general provisions of section 13-81-103. No such conflict exists here, as section 13-80-105 is totally silent on the effect of mental incompetency on the two-year period of limitation and the three-year period of repose applicable to medical malpractice claims.
714 P.2d at 897. In the case of a claim of a mental incompetent for injury sustained as a result of medical malpractice, therefore, *1084the tolling period created by section 13-81-103(l)(a) continues until the mental incompetency is removed or a “legal representative” is appointed, in which event the action must be filed within two years of such appointment. Section 13-81-101(2), 6 C.R.S. (1973), defines a “legal representative” to include a “guardian ... appointed by a court having jurisdiction of any person under disability,” but does not include a natural parent not so appointed.
C.
The defendants-appellees would distinguish Southard on the basis that Douglas Southard became mentally incompetent as an adult, while Steven Tenney had been so since birth. The parents of one whose mental incompetency arises from birth injuries, it is argued, would surely have discovered the injury by the time the child reached the age of six, and would have brought an action on his behalf out of a sense of responsibility for their child. Thus, the argument concludes, unlike a mentally incompetent adult who may have no one to look out for his rights until a legal representative is appointed, a mentally incompetent child who has natural parents does not need the additional protection provided by applying the general tolling provisions of section 13-81-103(l)(a) to the medical malpractice statute of limitations.
Such argument flies in the face of the plain language of the applicable statutes. Nowhere in these statutes is there any indication that the disability of mental incompetency is available only to adults. Section 13-81-101(3) includes a “mental incompetent” within the definition of “person under disability” with no qualifying or limiting language accompanying the former phrase. Section 13-80-105(3), 6 C.R.S. (1985 Supp.), limits the “disability” of minority to minors under six or to minors under eighteen with no natural or legal guardian, but no such limitation is placed on the disability of mental incompetency.
If the General Assembly had intended to limit medical malpractice actions brought by minors regardless of whether the minors were under any other disability, it could have made that intention clear, as have the legislatures of several other states. For example, Indiana’s medical malpractice limitation period for minors is similar to Colorado’s but goes on to state:
[Ejxcept that a minor under the full age of six (6) years shall have until his eighth birthday in which to file. This section applies to all persons regardless of minority or other legal disability.
Ind.Code Ann. § 16-9.5-3-1 (Burns 1983) (emphasis added). Similar provisions can be found in other states. See N.M.Stat.Ann. § 41-5-13 (1978) (three-year medical malpractice statute of limitations, with tolling provision giving minors under six until their ninth birthday in which to file, applies to all persons regardless of minority or other legal disability); Ohio Rev.Code Ann. § 2305.11(B) (Page 1985 Supp.) (four-year medical malpractice limitation period applies to all persons regardless of legal disability, except that minors under ten have until their fourteenth birthday to file); Texas Rev.Civ.Stat.Ann., art. 4590i, § 10.01 (Vernon 1986) (two-year medical malpractice limitation period, allowing minors under twelve until their fourteenth birthday in which to file, applies to all persons regardless of minority or other legal disability); Utah Code Ann. § 78-14-4(2) (1986 Supp.) (two-year limitation provision and four-year repose provision for medical malpractice claims apply to all persons, regardless of minority or other legal disability); Wyo.Stat. § 1-3-107 (1977) (two-year limitation period, with provisions allowing actions to be brought until a minor’s eighth birthday and until one year after the removal of a legal disability, applies to all persons regardless of minority or other legal disability). Since the Colorado legislature did not choose to make the periods of limitation and repose in section 13-80-105, 6 C.R.S. (1985 Supp.), unqualifiedly applicable to all claims filed on behalf of minors, regardless of the existence of a separate *1085and independent disability such as mental incompetency, we decline to do so here.7
We thus hold that the general tolling provisions of section 13-81-103(1)(a), 6 C.R.S. (1973), apply to a medical malpractice claim brought on behalf of a mentally incompetent person whether that person is a minor or an adult. Under section 13-81-103(1)(a), a legal representative appointed for the person under disability is allowed a period of two years after appointment within which to take action on behalf of the person under disability. Here, Steven’s parents were appointed co-guardians on September 8, 1980, and the suit was filed on August 10, 1982, a date within- two years after their appointment.
III.
We accordingly answer certified questions one and two as follows: (1) the 1977 amendments to the Colorado medical malpractice statute of limitations, § 13-80-105, 6 C.R.S. (1985 Supp.), did not bar this action, notwithstanding the fact that the action was not commenced within one year after the effective date of the 1977 amendments; and (2) the statutory periods of limitation and repose in section 13-80-105, 6 C.R.S. (1985 Supp.), were tolled in this case by reason of Steven Tenney’s mental incompetency until such time as his parents were appointed as co-guardians on September 8, 1980.
We find it unnecessary to answer question three — that is, whether the provisions of section 13-80-105(2), 6 C.R.S. (1985 Supp.), which state that “the limitations period shall not run unless a guardian ad litem is appointed to represent the minor child,” tolled the statute of limitations until the appointment of Steven Tenney’s parents as co-guardians. Our reason for declining to answer question three is that section 13-81-103(1), 6 C.R.S. (1973), establishes mental incompetency as an independent basis to toll the periods of limitation and repose applicable to a medical malpractice claim, and that this statutory toll continues until a legal representative is appointed, in which event the action must be filed within two years following the appointment. Since the instant claim was filed within two years following the appointment of Steven’s parents as co-guardians, we need not consider whether the statutory language of section 13-80-105(2), 6 C.R.S. (1985 Supp.), provided a separate basis to toll the periods of limitation and repose, in section 13-80-105(1), 6 C.R.S. (1985 Supp.).
The action filed by the Tenneys was not time-barred under Colorado law.
ROYIRA, J., dissents.. Question one as certified asked whether the action was barred "where brought by a fifteen-year old mentally incompetent person.” The claimant, however, is now twenty-four years old and was fifteen in 1977. We have accordingly rephrased the question in the interest of clarity.
. The third question incorrectly refers to "the third clause of the second sentence” of subsection (2) when in fact the pertinent statutory language is found in the third clause of the first sentence of subsection (2). The third question also refers to subsection (b)(2) of section 13-80-105, [6] C.R.S. [1985 Supp.], but the correct citation is subsection (2) of section 13-80-105.
. Section 13-80-105, 6 C.R.S. (1985 Supp.), states:
(1) Actions barred in two years. No person shall be permitted to maintain an action [for medical malpractice] ... unless such action is instituted within two years after the person bringing the action discovered, or in the exercise of reasonable diligence and concern should have discovered, the injury. In no event may such action be instituted more than three years after the act or omission which gave rise thereto, subject to the following exceptions:
*1081(a) If the act or omission which gave rise to the cause of action was knowingly concealed by the person committing such act or omission, or, if such act or omission consisted of leaving an unauthorized foreign object in the body of the patient, then such action may be instituted within two years after the person bringing the action discovered, or in the exercise of reasonable diligence and concern should have discovered, the act or omission;
(b) If the action is brought by or in behalf of a minor who was under six years of age on the date of occurrence of the act or omission for which such action is brought, then such action may be instituted within two years after said minor reaches six years of age.
(2) The limitations period provided for in subsection (1) of this section shall not run during any period when the said minor is under the age of eighteen years and has no natural or legal guardian, but such action may be instituted by or in behalf of said minor within two years after a legal guardian is appointed by a court of record or within two years after the person under such disability reaches eighteen years of age, whichever shall occur first; except that, if there is a discovered act or omission which could give rise to an action, the limitations period shall not run unless a guardian ad litem is appointed to represent the minor child. Any real party in interest may apply to the court for the appointment of such guardian ad litem. A real party in interest shall include the party against whom such an action may be brought.
(3) For purposes of this section only, "person under disability” means a minor under six years of age, a person under the age of eighteen years who does not have a natural or legal guardian, a mental incompetent, or a person under any other legal disability.
In 1986, the General Assembly repealed section 13-80-105, 6 C.R.S. (1985 Supp.), and enacted a new statute of limitations, which provides that all actions against any hospital, doctor, or other person involved in the healing arts shall be commenced within two years after the cause of action accrues. Ch. 114, sec. 1, § 13-80-102, 1986 Colo.Sess.Laws. 695, 696. The new statute of limitations further provides as follows:
Section 23. Effective date — applicability. (1) This act shall take effect July 1, 1986, and shall apply to claims for relief arising on or after said date.
(2)(a) Except as provided in paragraph (b) of this subsection (2), all actions commenced on or after July 1, 1986, to assert claims for relief arising prior to July 1, 1986, which are not barred by the statutory provisions amended by this act as said provisions existed prior to July 1, 1986, or by any other applicable statute of limitations shall be commenced on or before July 1, 1988.
(b) All actions commenced on or after July 1, 1986, to assert claims for relief arising prior to July 1, 1986, which are not barred by the statutory provisions amended by this act as said provisions existed prior to July 1, 1986, or by any other applicable statute of limitations shall be commenced on or before July 1, 1989, if the statutory provisions amended by this act provide a three-year statute of limitations or on or before July 1, 1992, if the statutory provisions amended by this act provide a six-year statute of limitations.
Ch. 114, sec. 23, 1986 Colo.Sess.Laws. 695, 706. We, of course, answer the questions certified to us on the basis of the pre-1986 statutory scheme and express no opinion as to the effect of the 1986 revisions.
. The sole reference to mental incompetency in section 13-80-105, 6 C.R.S. (1985 Supp.), is in subsection (3), which defines a "person under disability” as “a minor under six years of age, a person under the age of eighteen years who *1082does not have a natural or legal guardian, a mental incompetent, or a person under any other legal disability” (emphasis added). The only other place in the statute where the word "disability" occurs is in subsection (2), where it is used to refer specifically to persons under eighteen who have no natural or legal guardian.
. Section 13-81-103(1), 6 C.R.S. (1973), provides in relevant part:
Statute begins to run — when. (1) When in any of the statutes of the state of Colorado a limitation is fixed upon the time within which a right of action, right of redemption, or any other right may be asserted either affirmatively or by way of defense, or an action, suit, or proceeding based thereon may be brought, commenced, maintained, or prosecuted, and the true owner of said right is a person under disability at the time such right accrues, then:
(a) If such person under disability is represented by a legal representative at the time the right accrues, or if a legal representative is appointed for such person under disability at any time after the right accrues and prior to the termination of such disability, the applicable statute of limitations shall run against such person under disability in the same manner, for the same period, and with the same effect as it runs against persons not under disability. Such legal representative, or his successor in trust, in any event shall be allowed not less than two years after his appointment within which to take action on behalf of such person under disability, even though the two-year period expires after the expiration of the period fixed by the applicable statute of limitations;
******
(c) If the disability of any person is terminated before the expiration of the period of *1083limitation in paragraph (a) of this subsection (1), and no legal representative has been appointed for him, then such person shall be allowed to take action within the period fixed by the applicable statute of limitations, or within two years after the removal of the disability, whichever period expires the later.
The definition of a “person under disability” in section 13-81-101(3), 6 C.R.S. (1973), was amended by the General Assembly in 1986. The amended version retains a "mental incompetent” under the definition of a "person under disability." Ch. 114, sec. 3, § 13-81-101(3), 1986 Colo.Sess.Laws 695, 702.
. We discussed in Southard, 714 P.2d at 897, the reasons why section 13-81-103(1)(a), 6 C.R.S. (1973), creates a statutory toll to the two-year statute of limitations in section 13-80-105(1), 6 C.R.S. (1985 Supp.), when the claimant is mentally incompetent:
Although section 13-81-103(1)(a) speaks in terms of the running of the applicable statute of limitations against a person under disability represented by a “legal representative,” and not in terms of suspending or tolling the limitation period during the period of disability, there can be no question that the statute is intended to toll the applicable statute of limitations during the period of disability. Otherwise there would be no purpose in setting forth the conditions for removing the disability, as section 13-81-103 clearly does. The provisions of section 13-81-103, therefore, operate to suspend the running of the applicable statute of limitations until either the disability is removed or, as expressly provided in subsection (1)(a), a "legal representative" is appointed for the "person under disability.” See Public Service Co. of Colorado v. Barnhill, 690 P.2d 1248 (Colo.1984); Antonopoulos v. Telluride, 187 Colo. 392, 532 P.2d 346 (1975); Price v. Sommermeyer, 41 Colo.App. 147, 584 P.2d 1220(197(8]), aff’d, 198 Colo. 548, 603 P.2d 135 (1979). A "person under disability” is defined in section 13-81-101(3), 6 C.R.S. (1985 Supp.), to include a “mental incompetent,” thus duplicating in this respect the definition of a "person under disability" in section 13-80-105(3) of the medical malpractice statute of limitations and repose. A "legal representative” is a "guardian, conservator, executor, or administrator duly appointed by a court having juris-, diction of any person under disability or his estate.” § 13-81-101(2), 6 C.R.S. (1973).
We also elaborated on the reasons why the statutory toll of section 13-81-103(l)(a) applies equally to the three-year period of repose in section 13-80-105(1):
We are also satisfied that the tolling provisions of section 13-81-103(l)(a) with respect to claims by or on behalf of a "person under disability” apply equally to the three-year period of repose applicable to a medical malpractice claim. Section 13-81-103(l)(a) is plainly directed to any statute that fixes a limitation "upon the time within which a right of action ... or any other right may be asserted either affirmatively or by way of defense.” This all-encompassing language clearly applies to a statutory period of repose, which, by definition, limits the time within which a cause of action must be instituted regardless of whether the cause of action has yet accrued. Yarbro v. Hilton Hotels Corp., 655 P.2d 822, 825 (1983). When the language of a statute is plain and its meaning clear, it should be interpreted as written. Civil Service Employees Association v. Love, 167 Colo. 436, 448 P.2d 624 (1968).
714 P.2d at 897-98.
. Even though the question submitted to us asks whether the action is timely "on the theory that mental incompetence caused by defendants’ negligent conduct toll[s] the statute,” we emphasize that our affirmative answer to this question should not be read as implying that a different result would be reached if plaintiff Steven Ten-ney's, mental incompetence had been caused by something other than the alleged negligence of the defendants. Mental incompetence tolls the statute as set forth here regardless of its origin.