Development and preliminary validation of the focused analgesia selection test to identify accurate pain reporters

Abstract

Clinical trials of analgesics have been plagued with poor assay sensitivity due, in part, to variability in subjects’ pain reporting. Herein, we develop and evaluate the focused analgesia selection test (FAST), a method to measure patients’ pain reporting skills. Subjects with osteoarthritis of the hip, knee, and/or ankle with pain intensity of ≥3/10 on a 0–10 numerical rating scale were enrolled. Subjects underwent the FAST procedure, which consists of recording subjects’ pain reports in response to repeated administration of thermal noxious stimuli of various intensities applied on the arm with the Medoc® Thermal Sensory Analyzer II. Subjects also rated non-noxious stimuli consisting of visual contrast rating. After performing an exercise task, subjects also rated clinical pain and were asked to report whether their pain had increased, decreased, or stayed the same. Overall, 88 subjects were enrolled, and 83 were included in the analyses. FAST’s outcomes including the R2, intraclass correlation coefficient (ICC), and coefficient of variation (CoV) indicated that subjects’ pain reporting skills were widely distributed. Higher FAST ICC significantly predicted greater changes in clinical pain following exercise (p=0.017), whereas the visual contrast test did not predict postexercise pain. FAST is the first method that measures subjects’ pain reporting skills. Using FAST to enrich clinical trials with “good” pain reporters (with high FAST ICC) could increase assay sensitivity. Further evaluation of FAST is ongoing.

Validity of the cold pressor test and pain sensitivity questionnaire via online self-administration

“…In addition to supporting the validity of subjective and self-administered measures of pain sensitivity, our results also suggest that individuals differ in their ability to precisely and accurately rate pain, the latter measured by consistency with the observed factor structure, which aligns with other recent research [33,34]. However, apparent differences might also be explained by, for example, differences in general attentiveness or conscientiousness, rather than pain rating ability as such.…”

Accurate pain reporting training diminishes the placebo response: Results from a randomised, double-blind, crossover trial

“…In the first FAST study [ 13 ] the thermal version of the FAST was used in a cohort of osteoarthritis patients, while in the current study the mechanical FAST (and mechanical APRT) was utilized in a cohort of PDN patients. In both studies the FAST results correlated with changes in clinical pain, thus extending the external validity of this approach beyond stimulus modality and pain indication.…”

“…In a recent study, [ 13 ] we developed a method aimed to assess subjects’ pain reporting accuracy. The method (named FAST, the Focused Analgesia Selection Test) is based on recording subjects’ pain reports in a response to the administration of noxious stimuli of various intensities.…”

“…subjects’ pain reports accuracy). In this study [ 13 ] a cohort of 88 osteoarthritis of the hip, knee, and/or ankle subjects underwent the FAST, based on application of thermal noxious stimuli, at baseline, and then reported their current clinical pain before and after preforming an exercise (stairs climbing) aimed to induce changes in their clinical pain. Results demonstrated that pain reporting accuracy varied between subjects.…”

NEO6860, modality-selective TRPV1 antagonist: a randomized, controlled, proof-of-concept trial in patients with osteoarthritis knee pain

“…To be eligible, patients must have had a body mass index between 18.0 and 35.0 kg/m 2 ; a diagnosis of OA of the knee according to American College of Rheumatology guidelines (at least 3 of the following: patient age >50, morning stiffness <30 minutes, crepitus on active motion, bone tenderness, bone enlargement, or no palpable warmth of synovium); or grade I, II, or III Kellgren–Lawrence classification of an X-ray of the knee (performed 6 months or less before inclusion). Grade I patients were limited to a maximum of 50% of the total number of patients; a Numerical Rating Scale (NRS) score ≥4 (maximum 10) after staircase test (described below); a Western Ontario and McMaster Universities Osteoarthritis (WOMAC, 3.1 Index Likert, 24-hour recall questionnaire) pain subscale score ≥6 (maximum 20); and an R 2 of the Focused Analgesia Selection Task (FAST) 31 outcome value >0.65, indicating the patient's ability to report pain accurately (Most patients were recruited using the last 3 criteria, but some were included before final amendment using other cutoffs for pain intensity [PI], WOMAC, and FAST. In any case at least one pain assessment, PI or WOMAC, must have been above 40% of maximum value, and 0.65 was the lowest FAST cutoff value used during the study).…”