This study aimed to ascertain the association between self-reported pain intensity and vital signs in both emergency department (ED) patients and a subgroup of patients with diagnosed conditions known to produce significant pain.

We performed a retrospective analysis of real-time, archived data from an electronic medical record system at an urban teaching hospital and regional community hospital. We included consecutive ED patients ≥16 years old who had a self-reported pain intensity ≥1 as measured during triage, from March 2005 to December 2012. The primary outcome was vital signs for self-reported pain intensity levels (mild, moderate, severe) on an 11-point verbal numerical scale. Changes in pain intensity levels were also compared to variations in vital signs. Both analyses were repeated on a subgroup of patients with diagnosed conditions recognized to produce significant pain: fracture, dislocation, or renal colic.

We included 153,567 patients (mean age of 48.4±19.3 years; 55.5% women) triaged with pain (median intensity of 7/10±3). Of these, 8.9% of patients had diagnosed conditions recognized to produce significant pain. From the total sample, the difference between mild and severe pain categories was 2.7 beats/minutes (95% CI: 2.4−3.0) for heart rate and 0.13 mm Hg (95% CI: -0.26−0.52) for systolic blood pressure. These differences generated small effect sizes and were not clinically significant. Results were similar for patients who experienced changes in pain categories and for those conditions recognized to produce significant pain.

Health care professionals cannot use vital signs to estimate or substantiate self-reported pain intensity levels or changes over time.

We aimed to compare recalled information on medication use, self-care activities and pain intensity among primary care low back pain consulters with diary records of the same events.

Concerns are often expressed regarding the validity of recalled information about past experience of health events such as pain or its treatment. Comparing with information collected using daily diaries is one method of validating recalled findings.

Patients completed diaries recording their medication use, self-care activities and pain intensity each day for two weeks. Immediately following this period, patients completed questionnaires asking for recall of their medication use, self-care activities and least, worst, usual and current pain for the previous two weeks. The recalled information obtained from the questionnaires was compared with data from the daily diaries using intraclass correlation coefficients (ICC) and κ, with one-sided 95% confidence intervals.

All 29 participants returned 11 or more diaries. Validity of questionnaire-based recall for medication use and self-care activities was good, with everyone who reported use in the diaries also reporting this on the questionnaires (both κ = 1.0). However, some specific medications (eg, diclofenac) were over-reported in the questionnaires, and some self-care activities (eg, exercises) were under-reported. Combinations of pain intensity ratings were more accurate than single ratings; the mean of the recalled least, usual and current pain intensities was closest to the diary ratings (ICC 0.94, mean difference 0.13). The generalisability of these findings to other settings, recall periods and patient groups remains to be established.