Defendant appeals as of right from an order denying his petition for a change of custody and granting plaintiff’s petition for a change of domicile. We affirm.
Plaintiff and defendant were divorced in January 1994. The judgment of divorce granted the parties joint legal custody of their two-year-old daughter with physical custody awarded to plaintiff. Following the divorce, plaintiff allowed defendant liberal visitation beyond that ordered by the trial court and often asked the paternal grandmother to baby-sit the child in lieu of a hired baby-sitter. On July 28, 1997, the trial court entered a stipulated order signed by both parties changing custody to joint physical and legal custody. The order also provided that plaintiff would keep the child in the Owosso School District until she *20reached the age of majority and, if plaintiff moved away from Owosso, defendant would be given physical custody of the child.
In April 1998, plaintiff married a man who lives and works in California. In July 1998, plaintiff petitioned the trial court for change of domicile from Michigan to California and requested an assessment of child support. Defendant in turn filed a petition for change of custody and asked the trial court to enforce the July 28, 1997, stipulated order. Plaintiff then petitioned for change of custody and asked the trial court to set aside the stipulated order. At the conclusion of a four-day evidentiary hearing, the trial court set aside the stipulated order, denied defendant’s petition for change of custody, and granted plaintiff’s petition for change of domicile.
We apply three standards of review in custody cases. The great weight of the evidence standard applies to all findings of fact. A trial court’s findings regarding the existence of an established custodial environment and regarding each custody factor should be affirmed unless the evidence clearly preponderates in the opposite direction. Fletcher v Fletcher, 229 Mich App 19, 24; 581 NW2d 11 (1998), citing Fletcher v Fletcher, 447 Mich 871, 877-878; 526 NW2d 889 (1994). An abuse of discretion standard applies to the trial court’s discretionary rulings such as custody decisions. Id. Questions of law are reviewed for clear legal error. Fletcher, supra, 229 Mich App 24, citing MCL 722.28; MSA 25.312(8), and Fletcher, supra, 447 Mich 881. A trial court commits clear legal error when it incorrectly chooses, interprets, or applies the law. Fletcher, supra, 229 Mich App 24, citing Fletcher, supra, 447 Mich 881.
*21Defendant first argues that the trial court erred in setting aside the July 28, 1997, stipulated order. We disagree. Stipulated orders that are accepted by the trial corut are generally construed under the same rules of construction as contracts. See Limbach v Oakland Co Bd of Co Rd Comm’rs, 226 Mich App 389, 394; 573 NW2d 336 (1997); Eaton Co Bd of Co Rd Comm’rs v Schultz, 205 Mich App 371, 379-380; 521 NW2d 847 (1994). Like contracts, stipulated orders are agreements reached by and between the parties. Id. at 378-379. However, contract principles do not govern child custody matters. The Legislature imposed on trial courts, through the Child Custody Act, MCL 722.21 et seq.; MSA 25.312(1) et seq., the duty to review proposed changes in child custody to determine whether the changes would be in the best interests of the child. MCL 722.27(l)(c> MSA 25.312(7)(l)(c). While trial courts try to encourage parents to work together to come to an agreement regarding custody matters, the circuit court retains jurisdiction over the child until the child reaches the age of majority. The trial court cannot blindly accept the stipulation of the parents, but must independently determine what is in the best interests of the child. Lombardo v Lombardo, 202 Mich App 151, 160; 507 NW2d 788 (1993), citing West v West, 241 Mich 679, 683-684; 217 NW 924 (1928), and Ebel v Brown, 70 Mich App 705, 709; 246 NW2d 379 (1976).
In Napora v Napora, 159 Mich App 241; 406 NW2d 197 (1986), as in this case, the parties agreed to a change of custody that was later disputed by the custodial parent. The Napora Court held that the trial court erred in believing that it was required to uphold the stipulation of the parties:
*22Despite any agreement which the parties may reach in regard to the custody of their child, where a custodial environment is found to exist physical custody should not be changed absent clear and convincing evidence that the change is in the best interests of the child. [Id. at 246-247 (citation omitted)].
See also In re Ford Estate, 206 Mich App 705, 708; 522 NW2d 729 (1994), holding, in part, a stipulation between the parties was not binding because “the parties to a civil matter cannot by their mere agreement supersede procedures , and conditions set forth in statutes or court rules.” (citation omitted).
In the present case, the trial court entered the stipulated order to change custody without making any independent determination regarding the best interests of the child pursuant to the Child Custody Act. We conclude that the trial court erred in failing to make such a determination.1 As such, the trial court *24was obligated to set aside the July 28, 1997, stipulated order and make its own determination whether a change of custody would be in the child’s best interests pursuant to the Child Custody Act. Therefore, we hold the trial court properly set aside the stipulated order of July 28, 1997.
Defendant next argues that the trial court ignored the great weight of the evidence in failing to grant custody to him. We disagree.2 A custody award may be modified on a showing of proper cause or change of circumstances that establishes that the modification is in the child’s best interest. MCL 722.27(l)(c); MSA 25.312(7)(l)(c); Dehring v Dehring, 220 Mich *25App 163, 166; 559 NW2d 59 (19.96).3 However, when a modification of custody would change the established custodial environment of a child, the moving party must show by clear and convincing evidence that it is in the child’s best interest. Rummelt v Anderson, 196 Mich App 491, 494; 493 NW2d 434 (1992). A custodial environment is established if
over an appreciable tíme the child naturally looks to the custodian in that environment for guidance, discipline, the necessities of life, and parental comfort. The age of the child, the physical environment, and the inclination of the custodian and the child as to permanency of the relationship shall also be considered. [MCL 722.27(l)(c); MSA 25.312(7) (1) (c). ]
The trial court acknowledged that defendant and his family played important roles in the child’s life, but that, nevertheless, the custodial environment was with plaintiff as opposed to defendant. The trial court noted that this is not a case of plaintiff versus defendant and his mother, Sharon Jordan. In fact, the trial court opined that both plaintiff and defendant would fall short if they had to compete with Sharon Jordan for custody of the child. However, the trial court looked at the factors as they pertained to plaintiff and defendant, not including the extended family.
The evidence revealed that, during defendant’s parenting time, the child spent the majority of her time at Sharon Jordan’s house. Even on the weekends when defendant was not working, defendant would spend the day with the child, but the child usually slept at Sharon Jordan’s house rather than at defend*26ant’s house. In fact, defendant testified that the child stayed overnight with him less than five times a year. Defendant rarely spent time alone with the child without the presence of his mother and other relatives. The report of the independent psychologist, Dr. Heather Zak, indicated that the child had probably bonded more closely with the paternal grandmother and aunt than she had with defendant.
The trial court determined that the child had been with plaintiff since birth except for parenting time spent with defendant. The trial court further found that the child looked to plaintiff, as between the parents, for guidance and the other factors listed in MCL 722.27(l)(c); MSA 25.312(7)(l)(c). On the basis of these facts, we cannot conclude that the trial court’s determination that a custodial environment was established with plaintiff was against the great weight of the evidence.
Once it was determined that a custodial environment was established with plaintiff, it was incumbent on defendant to show by clear and convincing evidence that a change in custody was in the child’s best interests. Rummelt, supra at 494.
The trial court must examine the factors listed in MCL 722.23; MSA 25.312(3) to determine the best interests of the child. The trial court found that the parties were equal with regard to all the factors listed in MCL 722.23; MSA 25.312(3), except factors c, d, and e, which the trial court found to weigh in favor of plaintiff.
MCL 722.23(c); MSA 25.312(3)(c) examines each party’s capacity to provide food, clothing, and medical treatment. There was evidence that plaintiff voluntarily refused child support when defendant was out of *27work because of a broken leg. After defendant returned to work, plaintiff still did not request child support. The evidence showed that plaintiff was the primary caregiver and she provided food, clothing, and toys to the child on a daily basis. While there was evidence that defendant and his family gave the child gifts of clothing, this clothing usually stayed at their house and the child did not take the items when she left.
Defendant alleges that plaintiff failed to provide proper medical care for the child twice in the past. The trial court did not make a specific finding regarding either parent’s ability to provide medical care; however, in both instances cited by defendant, the facts show that the child received the necessary medical care. On the first occasion, the child was taken to the hospital by defendant’s mother while she was watching the child, but plaintiff did not go to the hospital to check on the child until the next day. On another occasion, plaintiff had taken the child to the hospital, but the hospital was unable to reach plaintiff regarding follow-up care because plaintiff’s phone was disconnected and registered letters were allegedly not claimed by plaintiff. Although plaintiff’s actions in both instances may not have been ideal, that does not prove that plaintiff is incapable of providing adequate medical care for the child. Therefore, we cannot conclude that the trial court’s findings were against the great weight of the evidence with regard to factor c.
MCL 722.23(d); MSA 25.312(3)(d) considers the length of time the child has lived in a stable, satisfactory environment, and the desirability of maintaining continuity. The trial court acknowledged that plaintiff *28had moved quite often. Nevertheless, the trial court concluded that the child’s home was with plaintiff wherever that may be and that parents could not be punished for having to move. As mentioned above, an established custodial environment existed with plaintiff in which she provided for the child’s daily needs. While defendant presented testimony that, on at least one occasion, the child was observed in unsanitary living conditions, the trial court made no mention of this incident in its findings of fact. The trial court may have concluded that the testimony was not credible or that the testimony related to an isolated incident. Questions of credibility are best left to the trier of fact. Blase v Appicelli, 195 Mich App 174, 179; 489 NW2d 129 (1992). The evidence as a whole demonstrated that the child was a normal, active, well-adjusted six year old and the trial court had no reason to believe that the child would not continue to thrive under plaintiff’s care. Considering the evidence as a whole, we cannot conclude that the trial court’s findings were against the great weight of the evidence with regard to factor d.
MCL 722.23(e); MSA 25.312(3)(e) evaluates the permanence, as a family unit, of the existing or proposed custodial home. The trial court found that with regard to this factor, both plaintiff and defendant had much to offer. However, the trial court favored plaintiff because of the fact that, to date, she had provided an adequate custodial home for the child. The trial court also considered the fact that plaintiff’s new marriage added stability to plaintiff’s life. Therefore, the trial court’s findings were not against the great weight of the evidence with regard to factor e.
*29For these reasons, we cannot conclude that the trial court’s findings under the Child Custody Act were against the great weight of the evidence. Consequently, we hold that the trial court did not err in denying defendant’s petition for change of custody.
Defendant finally argues that the trial court abused its discretion in granting plaintiff’s petition for change of domicile because the trial court rejected the testimony of Dr. Zak, the independent psychologist who evaluated the parties and recommended that plaintiff not be allowed to leave the state with the child. We disagree.
A trial court’s decision to allow a parent to remove a child from the state is reviewed for an abuse of discretion. Overall v Overall, 203 Mich App 450, 458-459; 512 NW2d 851 (1994). An abuse of discretion is found only in extreme cases in which the result is so palpably and grossly violative of fact and logic that it evidences a perversity of will or the exercise of passion or bias. Dacon v Transue, 441 Mich 315, 329; 490 NW2d 369 (1992).
This Court, in Overall, reiterated the standard for determining whether a change of domicile should be granted. Overall, supra at 458-459. Four factors must be considered:
“(1) whether the prospective move has the capacity to improve the quality of life for both the custodial parent and the child; (2) whether the move is inspired by the custodial parent’s desire to defeat or frustrate visitation by the noncustodial parent and whether the custodial parent is likely to comply with the substitute visitation orders where he or she is no longer subject to the jurisdiction of the courts of this state; (3) the extent to which the noncustodial parent, in resisting the move, is motivated by the desire to secure a financial advantage in respect of a continuing support obli*30gation; and (4) the degree to which the court is satisfied that there will be a realistic opportunity for visitation in lieu of the weekly pattern which can provide an adequate basis for preserving and fostering the parental relationship with the noncustodial parent if removal is allowed.” [Id., quoting Anderson v Anderson, 170 Mich App 305, 309; 427 NW2d 627 (1988).]
With regard to the first factor, the trial court found that plaintiffs marriage and move to California had the potential for improving both the child’s and plaintiff’s quality of life. The trial court noted that plaintiff’s husband earned a very respectable living and, judging from his appearance, demeanor, and testimony, he would likely continue to be a success. The trial court also considered plaintiffs desire to study the real estate business as a potential improvement to their quality of life. Plaintiff had testified that a career in real estate would allow her to work part-time, so she could fit her schedule around the child’s school schedule. The trial court stressed that it was not obligated to determine whether, in fact, the quality of life would improve, but instead was required to consider whether it had the potential to improve.
Additionally, we note that the trial court did not reject outright the recommendation of Dr. Zak. Rather, the trial court found that Dr. Zak confused the standard for change of custody with the standard for change of domicile. Dr. Zak opined that it would be in the child’s best interests to deny the change of domicile, but she did not conclude that it was in the best interests of the child to change custody to defendant. In fact, Dr. Zak’s recommendation was to have plaintiff’s husband move to Michigan so that the child could remain in the Owosso community and be raised *31by all the people that love and support her.4 Although defendant’s family, particularly his mother, play an important role in this child’s life, the role of the extended family cannot be the determining factor in denying a change of domicile. Instead, the trial court must consider whether the move has the capacity to improve the quality of life for both the custodial parent and the child and whether there will be a realistic opportunity to preserve and foster the parental relationship with the noncustodial parent.
The trial court found that the move did have the capacity to improve the quality of life for plaintiff and the child and that extensive summer and holiday visitation would preserve and foster the parental relationship with defendant. The trial court further found, on the basis of plaintiff’s allowance of liberal visitation in the past, that there was no evidence to suggest that the move was inspired by plaintiff’s desire to defeat defendant’s visitation rights or that she would not comply with the trial court’s order for visitation. Nor did the trial court find that defendant’s resistance to the move was motivated by a desire to secure a financial advantage.
On the basis of the evidence presented, we cannot conclude that the trial court’s decision to grant a change of domicile was an abuse of discretion.
Affirmed.
J. W. Fitzgerald, J., concurred.The dissent would hold that “[w]hen the parties are in agreement regarding a modification of the custodial arrangement . . . the court has the authority, but is not bound, to accept the parties’ stipulation without first specifically reexamining the best interest factors.” Post at 33-34. The dissent relies on Dick v Dick, 210 Mich App 576, 584-585; 534 NW2d 185 (1995), and Koron v Melendy, 207 Mich App 188, 191; 523 NW2d 870 (1994), in support of its conclusion. However, the decisions in those cases were based on stipulations involving the original judgments of divorce, not a modification of custody. To apply the reasoning from Dick and Koron to the case at bar would be contrary to the plain language of MCL 722.27(l)(c); MSA 25.312(7)(l)(c), which provides, in pertinent part:
The court shall not modify or amend its previous judgments or orders or issue a new order so as to change the established custodial environment of a child unless there is presented clear and convincing evidence that it is in the best interest of the child. [Emphasis added.]
The dissent focuses on the word “dispute” in § 7 of the Child Custody Act to suggest that the quoted provision applies only where the parties seek specific judicial intervention from the court. We opine that such a narrow reading of § 7 is unwarranted in light of well-settled principles of *23statutory interpretation. Statutory language should be construed reasonably, keeping in mind the purpose of the act. Barr v Mt Brighton Inc, 215 Mich App 512, 516; 546 NW2d 273 (1996). The first criterion in determining intent is the specific language of the statute. In re MCI Telecommunications Complaint, 460 Mich 396, 411; 596 NW2d 164 (1999). Every word within a statute should be presumed to have some meaning, and a construction that would render any part of a statute surplusage or nugatory should be avoided. Hoste v Shanty Creek Management, Inc, 459 Mich 561, 574; 592 NW2d 360 (1999). Unless defined in the statute, every word or phrase of a statute should be accorded its plain and ordinary meaning, taking into account the context in which the words are used. MCL 8.3a; MSA 2.212(1); Western Michigan Univ Bd of Control v Michigan, 455 Mich 531, 539; 565 NW2d 828 (1997).
The Child Custody Act is equitable in nature and, thus, should be liberally construed. MCL 722.26(1); MSA 25.312(6)(1); Frame v Nehls, 452 Mich 171, 176; 550 NW2d 739 (1996). Subsection 7(1) of the act reads in pertinent part:
If a child custody dispute has been submitted to the circuit court as an original action under this act or has arisen incidentally from another action in the circuit court or an order or judgment of the circuit court, for the best interests of the child the court may do 1 or more of the following:
The act does not define “child custody dispute.” Therefore, it is proper to consult dictionary definitions to determine its meaning. Popma v Auto Club Ins Ass’n, 446 Mich 460, 470; 521 NW2d 831 (1994); Ryant v Cleveland Twp, 239 Mich App 430; 608 NW2d 101 (2000). Dictionary definitions of the term “dispute” include
1. to engage in argument or debate. 2. to argue vehemently; quarrel. ... 3. to argue or debate about. 4. to argue against; call in question. 5. to quarrel or fight about; contest. 6. to strive against; oppose . . . 7. a debate, controversy, or difference of opinion. 8. a quarrel. [Random House Webster’s College Dictionary (1997).]
Blacks Law Dictionary (7th ed) defines the term as: “A conflict or controversy, esp. one that has given rise to a particular lawsuit.” Given those definitions and the act’s purpose of promoting the best interests and welfare of children, Frame, supra at 176, we read the language in § 7 in the greater context of the Child Custody Act to mean any case arising from divorce or otherwise where child custody is at issue. Thus, a child custody dispute, as that term is used in § 7 of the Child Custody Act, is any matter that relates to the custody of a child from the time the issue of custody arises until the child reaches the age of majority. This interpretation is supported by the fact that, from the time a court takes jurisdiction over a child custody dispute, all matters relating to the child’s welfare and upbringing, such as child support, parenting time, and changes of custody *24are implemented by order of the court. These orders would be unwarranted under the dissent’s interpretation of § 7. Thus, we believe that we have reasonably construed the text of § 7 and applied it accordingly. See Scalia, A Matter of Interpretation: Federal Courts and the Law (New Jersey: Princeton University Press, 1997), p 23.
It is also noteworthy that the dissent’s assertion that “[a]s with judicial acceptance of an original custody arrangement, implicit in a court’s acceptance of a modification agreement is an acknowledgment that the agreement is in the child’s best interest”, post at 35, n 2, is particularly inapplicable to the present case. The lower court record suggests the trial court did not consider, either implicitly or explicitly, if the stipulation was in the child’s best interest before entering its order. The fact that the stipulation was signed on behalf of the trial judge as well as the trial court’s discussion during the evidentiary hearing regarding the stipulation’s effect of precluding the court, “potentially forever,” from considering whether it was in the best interest of the child, suggest the stipulation was blindly accepted without any consideration of its effect on the child.
The trial court correctly determined that blind acceptance of the parties’ July 28, 1997, stipulated order changing physical custody, i.e., changing the established custodial environment, was improper absent clear and convincing evidence that it is in the best interest of the child.
Defendant preliminarily argues that the trial court erred in failing to allow the child’s doctor to testify regarding whether plaintiff provided adequate medical treatment for her daughter. However, defendant waived this issue by failing to cite authority to support this argument. Insufficiently briefed issues are deemed waived on appeal. Dresden v Detroit Macomb Hosp Corp, 218 Mich App 292, 300; 553 NW2d 387 (1996). Therefore, we will not address this issue.
Defendant contends that a change in circumstances exists in this case as a result of plaintiffs desire to move the child to California.
Dr. Zak would have plaintiffs new husband give up a lucrative career and move to Michigan to be with plaintiff. However, plaintiff’s husband testified during the hearing that he would not be able to find a comparable job with the same potential for growth in Michigan.