An appellate court reviews modifications of child support de novo on the record and will affirm the judgment of the trial court absent an abuse of discretion. Groseth v. Groseth, 257 Neb. 525, 600 N.W.2d 159 (1999); Smith-Helstrom v. Yonker, 253 Neb. 189, 569 N.W.2d 243 (1997); Welch v. Welch, 246 Neb. 435, 519 N.W.2d 262 (1994). Although in conducting a de novo review of a modification of a dissolution decree an appellate court reaches a conclusion independent of the trial court, where credible evidence is in conflict on a material issue of fact, the appellate court considers and may give weight to the fact that the trial court heard and observed the witnesses and accepted one version of the facts rather than another.