A novel methodology to integrate outcomes regarding perioperative pain experience into a composite score: Prediction model development and validation.

BACKGROUND

An integrated score that globally assesses perioperative pain experience and rationally weights each component has not yet been developed.

METHODS

A development dataset specific to adult Chinese patients undergoing orthopaedic surgery was obtained from PAIN OUT (1985 qualified patients of 2244). A more recent validation dataset obeying the same conditions was obtained from the Chinese Anaesthesia Shared-database Platform (1004 qualified patients of 1032). Outcomes were assessed using the International Pain Outcomes Questionnaire (IPO-Q), which comprises key patient-level outcomes of perioperative pain management, including pain experience and perceptions of care. Using principal component analysis and regression models, a composite score (CS) was inferred to integrate pain experience. The discrimination of the CS for dissatisfaction and desire for more pain treatment was compared with that of the worst pain score.

RESULTS

A CS was developed from the 12 items of the IPO-Q regarding pain experience. The weight for calculating the CS was worst pain 11, least pain 17, time spent in severe pain 11, interference with activity in bed 9, interference with breathing deeply or coughing 10, interference with sleep 9, anxiety 12, helplessness 12, nausea 0, drowsiness 2, itch 5 and dizziness 2. In external validation, the CS indicated superior discrimination to the worst pain in predicting dissatisfaction (p < 0.001) and desire for more pain treatment (p < 0.001).

CONCLUSIONS

This study introduced a methodology to integrate outcomes regarding perioperative pain experience into a CS, which was based on the weight of each item.

SIGNIFICANCE

This novel methodology sheds additional light on the riveting issue of carefully integrating several measures into a composite endpoint, which may be useful for quality improvement purposes when addressing the impact of a change in clinical practice.