'Sufficient Pain relief ' as a Practical Benchmark in Cancer Pain Management: A Prospective Study of Serial Pain Scores, Patient-rated Pain Relief and Perceived Sufficiency of Analgesics

Objectives: Serial pain scores are used to guide pain management but there can be variability in what constitutes 'adequate' pain relief for an individual patient. We aimed to evaluate how patient-rated sufficiency of pain relief corresponded to pain scores, pain relief scores, and the felt need for increasing analgesics. Material and Methods: Baseline and follow-up scores on the 11-point numerical rating scale (11-NRS) and verbal rating scale were obtained for116 patients with cancer pain. Patients used the pain relief sufficiency rating (PRSR) to rate pain relief as 'no reduction,' 'some reduction, but not enough,' 'sufficient reduction,' and 'very good reduction.' They also rated analgesics as 'sufficient' or 'insufficient.' Receiver-operating characteristic (ROC) curve analysis was used to compare PRSR responses with follow-up pain scores, patient rated percentage pain relief, and the perceived need for an increase in analgesics. Results: The 11-NRS had an area under the ROC curve of 94.2% against the PRSR. A pain score of three provided the best cutoff to identify adequate pain relief (88.2% sensitivity and 85.7% specificity). Follow-up verbal pain scores corresponded to PRSR categories (severe pain: no reduction; moderate pain: some reduction; mild pain: sufficient reduction and no pain: very good reduction). The PRSR identified 97.3% of patients who wanted analgesics increased and 85% of those who said pain medications were sufficient. Conclusion: The PRSR is a brief, simple and intuitive measure to elicit patient perceptions on the sufficiency of pain relief. Our findings suggest that it might be a useful tool in pain and symptom management.