Court Opinion

ID: 9796169
Source: CourtListenerOpinion
Date Created: 2023-08-31 03:51:01.513699+00
Date Added: 2024-06-11T08:48:44.013301
License: Public Domain

HOBBS, Justice.
We granted certiorari to review the court of appeals decision in Dillard v. Industrial Claim Appeals Office, 121 P.3d 301 (Colo.App.2005).1 The issue in this case is whether a claimant may combine a mental impairment rating with a physical impairment rating for the purpose of exceeding the then-applicable sixty thousand dollar cap in favor of the one hundred twenty thousand dollar cap, both of which are contained in section 8-42-107.5, C.R.S. (2005), of Colorado’s Workers’ Compensation Act.2 This section caps benefits from combined temporary disability payments and permanent partial disability payments. No claimant whose impairment rating is twenty-five percent or less may receive more than sixty thousand dollars from combined temporary disability payments and permanent partial disability payments; those claimants who have an impairment rating above twenty-five percent receive the benefit of the higher cap.
In the case before us, the division-sponsored medical examination (DIME) physician rated claimant’s whole person impairment at a total of 29%: 23% for the claimant’s cervical spine, 2% for the left hip, and 5% for mental impairment.
The 5% mental impairment rating, when combined with the physical impairments ratings and converted to a whole person rating, produced a DIME rating of 29%, pushing Dillard’s impairment rating above 25%. She therefore asserts entitlement to the higher cap contained in section 8-42-107.5. We disagree. Along with the administrative law judge, a panel of the Industrial Claim Appeals Office, and the court of appeals, we hold that section 8-42-107(7)(b)(III), C.R.S. (2005), precludes combining a mental impairment rating with a physical impairment rating for the purpose of obtaining the benefit of the higher cap set forth in section 8-42-107.5.
Accordingly, we uphold the judgment of the court of appeals.
*409I.
In 1999, Debra Dillard (“Dillard”) worked as an administrative assistant ‘for Pepsi Bottling Group (“Pepsi”), in Grand Junction, Colorado. On December 19 of that year, she slipped on ice in front of her workplace and hit her head on the sidewalk.
Dillard immediately complained of pain in her head and cervical region. She proceeded directly to the emergency room via an ambulance. At the hospital, doctors diagnosed her with scalp hematoma and a closed head injury.
Several days later, pain and stiffness in Dillard’s neck became unbearable and she again sought medical advice. An MRI uncovered damage to one and possibly two discs in Dillard’s cervical spine. After conservative treatments failed, doctors removed her C4-C5 disc and fused bones in her cervical spine together with plates and screws. When Dillard’s pain did not adequately subside, doctors repeated the operation for her C6-C7 disc.
Throughout this time, Dillard was prescribed Serzone for depression and Xanax for anxiety and complained that she could not sleep and often cried throughout the night. She blamed her emotional distress upon her physical inability to engage in many everyday (as well as recreational) activities, intense and constant pain, as well as a perceived threat to her marriage and family. However, Dillard did not initially claim disability benefits for mental impairment.
When Dillard reached maximum medical improvement, her attending physician determined that her total body permanent impairment rating was 20% of the whole person. He did not take into account Dillard’s anxiety and depression. Dillard received an independent medical examination. The independent medical examiner determined that Dillard’s whole person impairment rating was 29%, upon combining the impairment for Dillard’s depression and anxiety with her physical impairments.
Whether or not Dillard’s impairment rating should include the mental impairment rating as well as the physical impairment rating for purposes of the section 8^42-107.5 cap is the subject of this dispute. An impairment rating above 25% would entitle her to have the benefit of the higher cap for temporary disability and permanent partial disability payments under section 8-42-107.5.
According to the record, Dillard received $51,569.33 in temporary disability benefits and, in gross, is entitled to $79,969.89 in permanent partial disability benefits. Therefore, under the $60,000 cap, Dillard received $8,430.67dn permanent partial disability benefits. If she qualifies for the $120,000 cap she could receive substantially more.
II.
We hold that section 8-42-107(7)(b)(III), C.R.S. (2005), precludes combining a mental impairment rating with a physical impairment rating for the purpose of obtaining the benefit of the higher cap set forth in section 8^42-107.5, C.R.S. (2005).
A.
Standard of Review
This case concerns the correct construction of sections 8^42-107(7)(b)(III) and 8-42-107.5, C.R.S. (2005). We review questions of statutory construction de novo. People v. Cross, 127 P.3d 71, 73 (Colo.2006).
In construing the Workers’ Compensation Act, our objective is to effectuate the intent of the General Assembly; we construe the statutory provisions as a whole, reconciling potential conflicting provisions, when possible. Lobato v. Indus. Claim Appeals Office, 105 P.3d 220, 223 (Colo.2005); see also Resolution Trust Corp. v. Heiserman, 898 P.2d 1049, 1054 (Colo.1995) (“[I]f courts can give effect to the ordinary meaning of the words adopted by a legislative body, the statute should be construed as written since it may be presumed that the General Assembly meant what it clearly said.”).
When we construe a statute, we do not adopt a construction that renders words superfluous, or injects additional terms, that contravene the legislature’s obvious intent. Cross, 127 P.3d at 73.
*410B.
Mental Impairment Claims and Statutory Caps
The issue in this ease concerns temporary disability and permanent partial disability benefits under Colorado’s Workers’ Compensation Act.3 Temporary disability benefits compensate a worker for lost work while she recovers from work-related injuries. A worker receives temporary benefits until, among other possibilities, she reaches maximum medical improvement.4 §§ 8-42-105, - 106, C.R.S. (2005) (describing temporary total and temporary partial disability benefits).
Some workers never fully recover from their injuries. In such cases, when a worker reaches maximum medical improvement but still remains permanently disabled, she then receives permanent disability benefits. See §§ 8-42-107, -111 (describing permanent partial and permanent total disability benefits).
If a worker is only partially disabled on a permanent basis, the amount of time for which she is eligible to receive benefits is calculated differently based upon the type of injury she sustained: a scheduled injury, a nonseheduled injury, or a mental impairment. See § 8 — 42—107(l)(b)(2), (7)(b)(I), (8).
Scheduled injuries are generally injuries to limbs, eyes, or ears. See § 8 — 42—107(l)(b)(2) (listing scheduled injuries and compensation). They are referred to as “scheduled” injuries because they are compensated according to a strict schedule contained in the statute; for example, the loss of a hand below the wrist entitles a worker to 104 weeks of permanent partial disability payments. § 8-42-107(2)(c).
A nonseheduled injury is an injury not listed on the schedule in section 8-42-107(2). See 8-42-107(8) (describing nonseheduled injuries and their compensation). Permanent partial disability benefits for nonseheduled injuries are calculated according to a formula that includes a worker’s “medical impairment rating” and her “age factor.” § 8-42-107(8)(d).
Claims for mental impairment5 are defined in section 844-301(2)(a), C.R.S. (2005). Mental impairments involve no physical injury and stem from psychologically traumatic workplace events, not including stress or trauma from demotion, promotion, termination and other similar actions undertaken by an employer in good faith. Id. Mental impairments may also arise when a worker suffers a disability arising from an accidental physical injury that leads to a recognized permanent psychological disability. § 8-41-301(2)(a.5). Section 8^1-301(2)(d) provides that the mental impairment which is the basis of the claim must be, “in and of itself, either sufficient to render the employee temporarily or permanently disabled from pursuing the occupation from which the claim arose or to require medical or psychological treatment.”
*411Permanent partial disability benefits awarded for mental impairment are also limited: a worker is compensated for mental impairment with permanent partial disability benefits for no more than twelve weeks unless she is the victim of a violent crime at work or suffers from a “physical injury or occupational disease that causes neurological brain damage.” § 8-41-301(2)(b). Temporary disability benefits awarded for mental impairment are not cut off after twelve weeks but act as a set-off against permanent partial disability benefits once a worker reaches maximum medical improvement. City of Thornton v. Replogle, 888 P.2d 782, 785 (Colo.1995); Douglas R. Phillips & Susan D. Phillips, Colorado Workers’ Compensation Practice & Procedure § 3.12 (2005).
It often arises, as in the case before us, that a worker will sustain more than one type of injury. Prior to 1999, the act allowed workers who suffered both scheduled and nonseheduled injuries to combine their scheduled and nonseheduled injuries into one formula award. Mountain City Meat Co. v. Oqueda, 919 P.2d 246, 253 (Colo.1996).
Added in 1999, subsections 8-42-107(7)(b)(1) to (III), C.R.S. (2005), ended this system and mandated in the calculation of permanent partial disability benefit compensation that each type of injury shall remain separate and be compensated solely on the basis of applicable statutory schedule or benefit formula. The General Assembly added to the statute in this 1999 amendment a legislative declaration and the provision we construe in the ease now before us, which (1) provides for mental and emotional distress to be compensated under a different provision of the act and (2) prohibits such impairments from being combined with a scheduled or a nonseheduled injury. Ch. 103, sec. 1, § 8-42-107,1999 Colo. Sess. Laws 298, 299.
These amendments to the permanent partial disability provisions of the statute respond to our Moimtain City Meat decision. In that judgment, we held that “the scheduled injury must be converted to a whole person impairment rating and combined with the non-seheduled injury’s whole person impairment rating in calculating permanent disability benefits.” Mountain City Meat, 919 P.2d at 254.
As the General Assembly has the prerogative of doing, in reaction to Mountain City Meat, it precluded through its 1999 amendment combining mental impairments with physical impairments to reach a whole person rating. Subsection 8 — 42—107(7)(b)(I) sets out the legislative declaration of policy. It states that “scheduled injuries shall be compensated as provided on the schedule and .nonseheduled injuries shall be compensated as medical impairment benefits.” Id.
Subsection 8 — 42—107(7) (b) (II) separates the calculation of disability benefits for scheduled and non-scheduled injuries:
Where an injury causes a [scheduled injury], the loss set forth in the schedule found in said subsection (2) shall be compensated solely on the basis of such schedule and the loss set forth in said subsection (8) [the nonseheduled injury] shall be compensated solely on the basis for such medical impairment benefits specified in said subsection (8).
In regard to mental impairment claims, subsection 8-42-107(7)(b)(III) provides that “mental or emotional stress shall be compensated pursuant to section 8-41-301(2) and shall not he combined with a scheduled or a nonseheduled injury.” (Emphasis added).
Section 8-42-107.5, C.R.S. (2005), adopted in 1991, places a cap upon the total amount of temporary and permanent partial disability benefits that a worker may receive from all of her injuries. See ch. 219, sec. 16, § 8-42-107.5,1991 Colo. Sess. Laws 1291,1311. The version of section 8-42-107.5 in effect at the time Dillard suffered her injury caps total temporary and permanent partial disability benefits at either $60,000 or $120,000 based upon the worker’s impairment rating:
No claimant whose impairment rating is twenty-five percent or less may receive more than sixty thousand dollars from combined temporary disability payments and permanent partial disability payments. No claimant whose impairment rating is greater than twenty-five percent may receive more than one hundred twenty thousand dollars from combined temporary dis*412ability payments and permanent partial disability payments.6
Impairment ratings are calculated by reference to the American Medical Association’s Guides to the Evaluation of Permanent Impairment {“AMA Guides ”), (3d ed. rev. 1990). See § 8-42-101(3.7), C.R.S. (2005) (“[A]ll physical impairment ratings used under Articles 40 to 47 of this title shall be based on the revised third edition” of the AMA Guides); § 8-42-107(8)(b.5)(I)(A), (8)(c), C.R.S. (2005) (describing calculation of medical impairment ratings). We conclude that the wording of the 1999 amendment operates to prevent combining the mental impairment rating with a physical impairment rating into a whole person rating in order to reach the higher cap level contained in section 8-42-107.5.
C.
Application to This Case
Comparing the wording of the provisions at issue in this ease and giving each of them meaning in relationship to each other, we find that section 8 — 42—107(7)(b)(III), C.R.S. (2005), unambiguously bars a claimant from combining mental impairments with scheduled or nonscheduled injuries for the purpose of reaching the higher cap contained in section 8-42-107.5, C.R.S. (2005).
According to section 8-42-107(7)(b)(III), not only are mental impairments always compensated according to section 8-42-301(2), the legislature also clearly specified that “[mjental or emotional stress ... shall not be combined with a scheduled or a nonscheduled injury.” - This second phrase of 8-42-107(7)(b)(III) is the key to our analysis because Dillard would have us rule that it merely reiterates the phrase before it: “Mental or emotional stress shall be compensated pursuant to section 8412-301(2).”
However, the “shall not be combined” language is unique to section 8-42-107(7)(b)(III). The preceding subsection, section 8 — 42—107(7)(b)(II), contains nothing like it to prevent combining scheduled and nonscheduled injuries into a whole person impairment rating for the purposes of section 8-42-107.5. Thus, the mental impairment language, “shall not be combined with a scheduled or a nonscheduled injury,” must have meaning. That meaning, when applied to section 8-42-107.5, is that mental impairments are not to be combined with scheduled or nonscheduled injuries when calculating the applicability of the higher cap contained in section 8-42-107.5.
Our Mountain City Meat decision construed the then-applicable provisions of the act as awarding compensation based on combining injuries into a whole person rating in calculating permanent disability benefits. The General Assembly’s 1999 amendment provided for awards based on separate calculations for scheduled and nonscheduled injuries and mental impairments. In addition, it singled out a prohibition on mental impairments being combined with physical injuries.
Dillard’s case for the higher benefit cap rests on combining her mental impairment with physical impairments into a whole person rating, which is what the DIME physician in this case did. Contrary to Dillard’s contention, the legislature’s treatment of permanent partial disability mental impairment claims is plain. The words “shall not be combined with a scheduled or a nonscheduled injury” in section 8-42-107(7)(b)(III) mean literally what they say.
In regard to mental impairment claims, the AMA Guides support the legislature’s intent to prevent the combination of mental impairment with physical impairment in assigning a whole person rating. According to the AMA Guides, an “impairment rating” roughly represents in percentage form the extent to which a person’s health status is altered by injury. American Medical Association, supra at 1. Generally, physicians combine all types of injuries into a “whole person” assessment. Id. at xviii (emphasis added). The AMA Guides even contain charts for the combination of different types of injuries. Id. at 254-*41356. However, mental impairments are not included in these charts. The AMA Guides clearly state in regard to mental impairments that “there is no available empirical evidence to support any method for assigning percentage of impairment of the whole person .... ” Id. at 240. The AMA Guides clearly explain:
Eventually research may support the direct link between medical findings and percentage of mental impairment. Until that time the medical profession must refine its concepts of mental impairment, improve its ability to measure limitations, and continue to make clinical judgments.
Id. at 241.
Dillard’s assertion of her entitlement to the higher cap contained in section 8-42-107.5 rests on the assertion that the General Assembly intended for mental impairments to be combined with physical impairments in calculating a whole person rating. We conclude that the General Assembly clearly intended otherwise. It prevented combining mental impairment injuries with scheduled and nonscheduled injuries to reach a whole person rating. The DIME physician in Dillard’s case contravened the legislature’s intent in calculating a 29% whole person rating for her. § 8-42-107(7)(b)(III).
D.
Equal Protection Challenge
The court of appeals disagreed with Dillard’s alternate contention that sections 8-42-107.5 and 8-42-107(7)(b)(III), so construed, violate Colorado and federal equal protection guarantees. See Dillard, 121 P.3d at 305-06. We agree with the court of appeals that no equal protection violation arises therefrom.
Access to Workers’ Compensation benefits is not a fundamental right and Dillard does not contend that she is a member of a suspect class. We therefore apply a rational basis analysis to Dillard’s equal protection claim. Garhart v. Columbia/Healthone, L.L.C., 95 P.3d 571, 583 (Colo.2004); Culver v. Ace Elec., 971 P.2d 641, 646 (Colo.1999).
Under the rational basis test, the party asserting the statute’s unconstitutionality must show that the classification lacks a legitimate governmental purpose and, without a rational basis, arbitrarily singles out a group of persons for disparate treatment in comparison to other persons who are similarly situated. Garhart, 95 P.3d at 583 (citing Culver, 971 P.2d at 646); accord Pace Membership Warehouse v. Axelson, 938 P.2d 504, 506 (Colo.1997). If any conceivable set of facts would lead to the conclusion that a classification serves a legitimate purpose, a court must assume those facts exist. Christie v. Coors Transp. Co., 933 P.2d 1330, 1333 (Colo.1997); Culver, 971 P.2d at 651.
The rational basis for section 8-42-107(7)(b)(III) and section 8-42-107.5 is to lower costs in the Workers’ Compensation system. This can be a legitimate governmental purpose. Culver, 971 P.2d at 652 (listing “maintaining the fiscal integrity of the workers’ compensation system; allocating the fiscal burden equitably among funding sources, and controlling costs to employers while providing legislatively-intended benefits to injured workers” as possible legitimate government purposes). Nevertheless, the General Assembly cannot arbitrarily single out certain individuals for disparate treatment for the mere sake of administrative convenience or sacrifice the rights of one group merely because more money in the Workers’ Compensation system allows .higher benefits for everybody else. Indus. Claim Appeals Office v. Romero, 912 P.2d 62, 68, 69 (Colo.1996).
The General Assembly’s treatment of mental impairment claims demonstrates a rational approach to circumscribing the conditions and amounts payable for such claims. We have previously held that the statutory scheme limits only permanent partial disability benefits paid for mental impairment to twelve weeks, and offsets any temporary disability benefits paid for mental impairment against any award of permanent partial disability benefits for mental impairment. Replogle, 888 P.2d at 782-83.
In our Replogle opinion we observed that the General Assembly’s choice of mental impairment provisions was aimed at containing *414costs while, at the same time, awarding mental impairment benefits to qualified claimants. Id. at 785. Dillard’s equal protection appeal assumes that because the legislature allows a claimant to combine scheduled and nonscheduled physical impairments for purposes of determining the impairment rating in section 8-42-107.5, it must allow the combination of mental with physical impairments in the same cap calculation. However, the legislature can rationally take into account that mental or emotional distress claims are not as susceptible to numerical analysis as physical injuries.
Our appellate court decisions recognize that mental impairments can be difficult to ascertain. See Davison v. Indus. Claim Appeals Office, 84 P.3d 1023, 1032 (Colo.2004) (observing that the General Assembly intended mental impairment provisions of the Workers’ Compensation Act to help in eliminating frivolous claims while acting to evaluate and pay bona fide claims); Colo. AFL-CIO v. Donlon, 914 P.2d 396, 403 (Colo.App.1995) (stating that General Assembly rationally promotes cost efficiency in Workers’ Compensation system by circumscribing compensation for injuries that are neither physical nor the result of workplace violence). Given their more imprecise nature, the General Assembly can rationally create a system for mental impairment claims when it seeks to contain costs by limiting the extent to which mental impairment injuries can increase a worker’s benefits.
In view of the General Assembly’s rationally-based choice in addressing mental impairment claims, we hold that Dillard’s equal protection violation claim does not succeed. The legislature’s line drawing need not be perfect. See, e.g., Pace Membership Warehouse, 938 P.2d at 507 (“Simply because a statutory classification creates a harsh result in one instance does not mean that the statute fails to meet constitutionality requirements under the rational basis standard.”); Duran v. Indus. Claim Appeals Office, 883 P.2d 477, 484 (Colo.1994) (“Given the almost limitless array of potential injuries and their impact on the ability to work, any line drawn by the legislature will necessarily be imperfect.”).
III.
Accordingly, we affirm the judgment of the court of appeals.
MULLARKEY, C.J., dissents, and MARTINEZ, J., joins in the dissent.

. We granted certiorari on the following issue:
Whether the court of appeals erred in applying section 8-42-107.5, C.R.S., which is a section of the workers’ compensation act which applies to the total amount of compensation that is available to injured workers based upon the severity of their injuries, by using section 8-42-107(7)(b)(I) and (III), C.R.S., which is the section of the act that determines the type of impairment or methodology of computing payment for impairment, to deprive or further limit injured workers’ permanent disability benefits.
(Emphasis in original).

. Effective January 1, 2006, the General Assembly revised section 8-42-107.5 to increase these respective caps to seventy-five thousand dollars and one hundred fifty thousand dollars.

. This dispute does not concern an employer's obligation to pay medical bills under the Workers' Compensation Act of Colorado. See Grover v. Indus. Comm'n of Colo., 759 P.2d 705, 709-12 (Colo.1988) (stating that medical benefits are separate from disability benefits and may be awarded concurrently); see also § 8-42-101, C.R.S. .(2005) (describing employer's obligation to furnish medical aid).

. According to section 8-40-201(11.5), C.R.S. (2005):
"Maximum medical improvement'' means a point in time when any medically determinable physical or mental impairment as a result of injury has become stable and when no further treatment is reasonably expected to improve the condition. The requirement for future medical maintenance which will not significantly improve the condition or the possibility of improvement or deterioration resulting from the passage of time shall not affect a finding of maximum medical improvement. The possibility of improvement or deterioration resulting from the passage of time alone shall not affect a finding of maximum medical improvement.

.In terms of Colorado's Workers' Compensation system, mental impairment benefits are rather new. Colorado's General Assembly passed Colorado's first Workers’ Compensation Act in 1915. See Martin v. Montezuma-Cortez Sch. Dist. RE-1, 841 P.2d 237, 242 (Colo.1992). The General Assembly did not add claims for "mental or emotional stress” and related injuries until 1986. See ch. 73, sec. 3, § 8-52-102, 1986 Colo. Sess. Laws 520, 520-21. For a comprehensive history of mental impairment claims nationwide, see 3 Arthur Larson & Lex K. Larson, Larson’s Workers’ Compensation Law § 56.03 to 56.04 (2005).

. Prior to reaching maximum medical improvement, a worker's benefits are not cut-off. Donald P. Murphy Contractors, Inc. v. Indus. Claim Appeals Office, 916 P.2d 611, 613 (Colo.App.1995). However, workers who receive either up to or in excess of their allotted cap in temporary disability benefits receive no permanent partial disability benefits. Id. at 614.