Assessing the Construct Validity and Internal Reliability of the Screening Tool Test Your Memory in Patients with Chronic Pain

PLoS One. 2016 Apr 27;11(4):e0154240. doi: 10.1371/journal.pone.0154240. eCollection 2016.

Abstract

Patients with chronic pain often complain about cognitive difficulties, and since these symptoms represent an additional source of suffering and distress, evaluating the cognitive status of these patients with valid and reliable tests should be an important part of their overall assessment. Although cognitive impairment is a critical characteristic of pain, there is no specific measure designed to detect these effects in this population. The objective was to analyze the psychometric properties of the "Test Your Memory" (TYM) test in patients with chronic pain of three different origins. A cross-sectional study was carried out on 72 subjects free of pain and 254 patients suffering from different types of chronic pain: neuropathic pain (104), musculoskeletal pain (99) and fibromyalgia (51). The construct validity of the TYM was assessed using the Mini-Mental State Examination (MMSE), Hospital Anxiety and Depression Scale (HADs), Index-9 from MOS-sleep, SF-12, and through the intensity (Visual Analogical Scale) and duration of pain. An exploratory factor analysis was also performed and internal reliability was assessed using Cronbach's alpha. After adjusting for potential confounders the TYM could distinguish between pain and pain-free patients, and it was correlated with the: MMSE (0.89, p<0.001); HAD-anxiety (-0.50, p<0.001) and HAD-depression scales (-0.52, p<0.001); MOS-sleep Index-9 (-0.49, p<0.001); and the physical (0.49, p < .001) and mental components (0.55, p < .001) of SF-12. The exploratory structure of the TYM showed an 8-factor solution that explained 53% of the variance, and Cronbach's alpha was 0.66. The TYM is a valid and reliable screening instrument to assess cognitive function in chronic pain patients that will be of particular value in clinical situations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Chronic Pain / complications*
  • Cognition
  • Cognitive Dysfunction / complications
  • Cognitive Dysfunction / diagnosis*
  • Cross-Sectional Studies
  • Female
  • Fibromyalgia / complications*
  • Humans
  • Male
  • Memory
  • Middle Aged
  • Musculoskeletal Pain / complications*
  • Neuralgia / complications*
  • Psychometrics / methods*
  • Reproducibility of Results

Grant support

This study was funded by the Grünenthal Foundation with an unrestricted grant for data collection and analysis. The authors are also grateful to the External Chair of Pain for the funding that allowed them to carry out this research, collaboration between the University of Cádiz and the Grünenthal Foundation. No member of Grünenthal Foundation staff had any role in the interpretation of data, in the writing of the report or in the decision to submit the paper for publication to the journal.