How Can We Improve the Accuracy of Routine Pain Screening?

How Can We Improve the Accuracy of Routine Pain Screening? L.R. Shugarman RAND Corporation VA HSR&D Center for the Study of Healthcare Provider Behavior, VA of Greater Los Angeles

Colleagues • K.A. Lorenz, Study PI • C.D. Sherbourne • L.V. Rubenstein • L. Wen • A. Cohen • J. Goebel • A. Lanto • S. Asch, Study Co-PI

Background • Despite available, effective treatment, clinicians and patients often have trouble achieving adequate pain control • Although there is widespread use of the `5th vital sign´ in the VA, its accuracy is unclear.

Objectives • Compare routine pain rating during vital sign intake to the same pain scale applied under ideal research conditions and to a gold standard measure, the Brief Pain Inventory (BPI) • Distinguish variation associated with instrumentation from that associated with routine measurement processes

Methods • Randomly sampled (March 2006-April 2007) veterans in primary care, urgent care, women’s health, oncology and cardiology clinics • 19 clinics from 2 hospitals, 6 affiliated sites in 3 large urban counties (Los Angeles, Ventura, and Orange) • Surveyed patients, their nurses, & treating providers • Patients surveyed immediately following clinic visit • Additional measures derived from chart review

Measures • Numeric Rating Scale (NRS) – 0-10 pain rating • Most commonly used method for assessing pain • NRS of 5+ = moderate/severe pain • Brief Pain Inventory (BPI) – developed by the WHO • Measures pain intensity and pain interference with various activities • Demonstrated reliability across patient populations and settings • Study measures: • NRS gathered during vital sign intake (Nurse-NRS) – from chart review • NRS gathered under research conditions (Research-NRS) – from patient survey • BPI-24 hours, BPI-one week, BPI-interference – from patient survey

Analysis • Intraclass correlation used to assess agreement between Research-NRS and Nurse-NRS and Nurse-NRS and BPI • Determined sensitivity/specificity of cutpoints on the Nurse-NRS to BPI (gold standard) by fitting ROC curves and calculated the area under the curve (AUC) • Variation in agreement further evaluated: • Did RN ask patient to rate pain on 0-10 scale? • Has patient’s pain changed since arrival at clinic?

Results – Sample Characteristics (N=627)

Direction of Difference in Ratings Between Nurse-NRS and Research-NRS Ratings

Intraclass Correlations Among Pain Rating Measures

Results • AUC for Nurse-NRS compared to Research-NRS was 0.78 for a cutoff of 5 and 0.77 for a cutoff of 7 • Similar AUC results found for Nurse-NRS compared to BPI-24 hour and BPI-last week • Nurses more likely to underestimate pain if they did not use 0-10 scale • Agreement attenuated when patient pain changed

Limitations • VA system institutionalized routine pain screening in the last decade; as such, findings may conservatively estimate the challenges of consistent implementation in more diverse, non-VA settings • Study limited to outpatient evaluation of the 5th vital sign

Conclusions • Accuracy of the 5th vital sign is moderate • Nurses may not always use the 0-10 NRS to properly quantify pain levels • Nursing staff training in pain measurement may be warranted

How Can We Improve the Accuracy of Routine Pain Screening?