Not every change is meaningful. Pay attention to a change when:

• It is large. A change of 10 points or more in a group with enough responses deserves a look.
• It appears across groups. A drop in several age bands is more convincing than a drop in one.
• Comments support it. A drop in a rating paired with comments about the same issue is strong evidence.

Be cautious with small groups. In a group with 4 responses, one family changing its answer moves the result by 25 points, which can look like a major trend.