Committment problems

I have a checklist that has several questions and that the final part is the rating (Commendable 100%, Trained 99%-80%, Practiced 79%-65%, or Untrained 64% or less) based on the overall score. The problem is that if the value changes, the rating doesn't change along with it (86% will still show commendable for example).  Also, there are two check boxes that if either one is checked, then the score is automatically set to 0% and rating to "Untrained (Critical)."

var score = this.getField("949 Score").value;

if (score == 1) event.value = "Commendable";

else if (score <= .99 && score >= .80) event.value = "Trained";

else if (score <= .79 && score >= .65) event.value = "Practiced";

else if (score <= .64) event.value = "Untrained";

if (this.getField("949 Q1 Critical").value == "Yes") event.value = "Untrained (Critical)";

if (this.getField("949 Q4 Critical").value == "Yes") event.value = "Untrained (Critical)";