Pain Management Index (PMI) scores were found to be inversely associated with the percentage of patients who experience pain interference, indicating that negative PMI scores may not always reflect inadequate pain management, according to a study published in BMC Palliative Care.
Investigators conducted a prospective cross-sectional study in which they examined the data from 1156 patients (average age, 62.9) who were hospitalized with cancer-related pain. Using different cutoff points, the researchers were able to evaluate the predictive validity of PMI scores for pain interference.
On average, patients within this cohort reported pain using a Numerical Rating Scale 5.8 times, with a mean value of 5.2 vs 2.0 in patients with and without pain interference, respectively (P <.001). Lower PMI scores were found to be associated with a higher percentage of patients with pain interference (P <.001).
A large percentage of patients with PMI scores of –2 or –3 reported experiencing pain interference; this percentage was smaller in participants with PMI scores of –1. The percentage of patients with pain interference was lower in participants with PMI scores of –1 vs 0 (36.6% vs 52.4%, respectively; P <.001).
Sensitivities of PMI scores for predicting pain interference were 0.16 for scores >–1, 0.37 for scores >0, and 0.67 for scores >1. Respective corresponding sensitivities were 0.95, 0.71, and 0.53.
The researchers noted certain limitations, such as an inability to generalize findings to other settings due to the fact that this study was conducted at one cancer care hospital.
“Our findings … indicate that judging the quality of pain management solely on PMI scores is an oversimplification of a complex issue. The PMI is effective in promoting assessment of care in broad settings; however, detailed interpretation by other means would facilitate further improvement in assessment of pain management,” concluded the study authors.
Sakakibara N, Higashi T, Yamashita I, Yoshimoto T, Matoba M. Negative pain management index scores[published online August 24, 2018]. BMC Palliative Care. doi:10.1186/s12904-018-0355-8