What is the test for reversing an order denying a petition to terminate parental rights?

In the present case, the trial court based its order on factors that were irrelevant to the statutory analysis and were unsupported by the evidence. As such, the order denying the petition to terminate parental rights constituted an abuse of discretion and must be reversed. (See Linder v. Thrifty Oil Co. (2000) 23 Cal.4th 429, 436 ["an order based upon improper criteria or incorrect assumptions calls for reversal ' "even though there may be substantial evidence to support the court's order" ' "].)

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