Til måling af primær effekt blev der anvendt en Visuel Analog Skala (VAS- skala) til måling af smerteintensitet.
Two short-term studies, 95-001 (malignant pain) and 96-002 (non malignant pain), involving 366 patients, demonstrated the efficacy of IT ziconotide in severe chronic pain using the percent change in Visual Analog Scale of Pain Intensity (VASPI) as the primary efficacy measure.