Start with who was compared
The published trial assigned fifty participants to static VR or adaptive VR with tactile feedback. Mean pain after venipuncture was 5.0/10 and 1.8/10 respectively.
These were different groups. A diagram that suggests one child’s pain fell from five to one-point-eight would misrepresent the design. The result describes a between-group difference.
Understand the denominator
Subtracting 1.8 from 5.0 gives 3.2. Dividing by the static group mean yields a relative difference of 64%. The denominator is the comparator group’s mean pain score—not the number of patients.
It therefore does not mean sixty-four percent of children benefited, or that every child’s pain was reduced by that amount. It is also not a usual-care comparison, because both groups used VR.
Individual observations and experience ratings
Six of twenty-five adaptive-group participants reported 0/10 pain. This does not guarantee a pain-free procedure. Similarly, eighty-four percent rated the experience “Very Effective”; that figure describes a response category, not an eighty-four percent pain reduction.
Read the source and the boundaries
The study’s sample size, setting and combined intervention matter. A hospital should evaluate the full publication, current product configuration and relevant local requirements rather than relying on a percentage alone.