Patients were found to score worse on average on 4 commonly used chronic pain questionnaires when they had a greater number of pain sites, were unemployed. or had injury compensation cases, or when their pain was the result of a motor vehicle accident or injury at work or home, according to a study published in Pain.
To improve interpretation of aggregate scores on chronic pain questionnaires in clinical trial and clinical practice settings, the researchers collected data from 13,343 heterogeneous patients (average age, 52.7 years) who were seen at one of 36 pain clinics in Australia and New Zealand. Included patients had completed a standardized assessment tool: the Brief Pain Inventory, the Depression Anxiety and Stress Scales (DASS), the Pain Self-Efficacy Questionnaires, or the Pain Catastrophizing Scale.
The mean Brief Pain Inventory severity score in this cohort was 6.4 on a 0 to 10 scale (ie, moderate to severe), and the mean interference score was 7.0. The mean DASS depression score was 20.2 on a 0 to 42 scale (ie, moderate to severe), the mean DASS anxiety score was 14.0 (ie, moderate), and the mean DASS stress score was 21.0 (ie, moderate). The mean Pain Self-Efficacy Questionnaires score was 20.7 on a 0 to 60 scale, and the mean Pain Catastrophizing Scale scores for rumination, magnification, helplessness, and total were 10.0, 5.9, 14.1, and 29.8, respectively, on a 0 to 52 scale.
Men were found to have worse scores than women on some of the questionnaires. Scores tended to worsen with age until the 31 to 50 age range, after which scores were found to improve. Scores also worsened with an increased number of pain sites and in patients who were unemployed, were involved in injury compensation cases, or had a triggering event related to a motor vehicle accident or an injury at work or home.
Limitations to this study include a lack of data on patients with chronic pain who could not complete the questionnaires because of language constraints or low literacy.
“The large size of this dataset and the widespread source of the data indicate these data can be used to interpret an individual’s score as well as the mean of a sample of individuals for each sub-scale of the 4 questionnaires reported, taking into account information about sex, age, or pain sites,” noted the study authors.
Nicholas MK, Costa DSJ, Blanchard M, Tardif H, Asghari A, Blyth FM. Normative data for common pain measures in chronic pain clinic populations: closing a gap for clinicians and researchers [published online January 25, 2019]. Pain. doi: 10.1097/j.pain.0000000000001496