Pain assessment in patients with low back pain: comparison of weekly recall and momentary electronic data.

UNLABELLED: Electronic data collection for monitoring pain has become increasingly popular in clinical research. Past research has shown that electronic diaries improve the timeliness of receipt of data, contribute to higher rates of compliance, and are preferred by patients over paper diaries, and this research suggests that electronic diaries that capture current pain at the moment of reporting result in more reliable ratings than recalled pain ratings. This study compared differences of momentary pain intensity ratings on an electronic visual analog scale (VAS) with weekly recalled pain on a 0 to 10 scale. We asked 21 patients with chronic low back pain to monitor their current pain at least once a day by using a VAS for up to 1 year with a palmtop computer. They were also called once a week and asked to rate their recalled weekly pain orally on a numeric scale from 0 to 10. Patients entered data electronically on average 357 times, for an average of 7.8 times a week. We found that (1) weekly recalled pain agreed highly (r > .90) with averaged momentary pain assessments, (2) neither frequency of electronic monitoring nor variability in momentary pain ratings (high standard deviations) contributed to degree of agreement between momentary and recalled pain, and (3) a ceiling effect was observed in VAS pain ratings as compared with numeric pain ratings. These findings suggest that, among many individuals, weekly recalled pain might be just as useful as momentary data collected through electronic data entry. PERSPECTIVE: Some believe that remembered pain is problematic because of recall bias and that data from frequent momentary pain ratings with electronic diaries are more valid. This study demonstrates that recalled pain is as valid as momentary data for many patients.

Electronic diaries for monitoring chronic pain: 1-year validation study.

Electronic data collection for monitoring pain has become increasingly popular in clinical research. However, no direct comparison has been made between electronic diaries and self-report paper diaries or phone interviews. We asked 36 patients with chronic low back pain to monitor their pain for 1 year; 20 of them used both a palmtop computer and paper diaries, and 16 used paper diaries alone. All patients were called once a week and asked to rate their pain. Regression analyses with a measurement error model were run on hourly pain scores recorded by both palmtop computer and paper diaries. Ratings of pain intensity were highly reliable between data recorded with a palmtop computer and with data from paper diaries. Patients who monitored their pain with the palmtop computer entered data on average 6.75 times a week and were 89.9% compliant with daily monitoring throughout the year. Two-way messaging available through the palmtop computer seemed to encourage continued use of the device. Internal consistency of reporting and correlations with phone reports and standardized measures were highly significant, suggesting that data from electronic diaries are both reliable and valid. Patients using electronic diaries preferred them to paper diaries and showed much higher rates of compliance and satisfaction over the 1-year trial.