The Graphical Index of Pain: a new web-based method for high-throughput screening of pain

This article is the first to present the Graphical Index of Pain (GRIP), a new user-friendly web-based method for high-throughput screening of pain. The long-term goal of the method is to improve global standardization of pain measurements. GRIP consists of a hierarchical body map with 10 first-tier body regions, and a second tier with multiple pain loci (167 among men, 168 among women), which provides detailed information about pain location and distribution. Follow-up questions for first-tier regions include the following pain characteristics: onset, episode frequency, episode duration (including constant pain), intensity, bothering, depth of pain, and effects on sleep and daily activities. The first implementation of GRIP was in the Tromsø Study (2015-2016), a population-based study of adults aged 40 to 99 years. In total, 21,083 individuals participated in the study, and 96% (n = 20,263; age 40-96 years) completed GRIP. Pain intensity at first-tier regions and pain location and distribution at second-tier regions are in this article presented by sex-stratified customized heat maps showing large sex difference. Mean time to mark the first- and second-tier regions was 74 seconds. In conclusion, GRIP allows for high-resolution assessment and presentation of pain location and distribution with minimal use of time.