Does Patients' Perception of Improvement following a Pain Management Programme, Match Reported Minimally Clinically Important Differences?

Purpose

Clinical outcomes for patients attending a pain management programme were evaluated to determine whether patients who rated an improvement on a Global Impression of Change Score, achieved mean changes in BPI that were consistent with 'acceptable' change, and to determine mean changes on other outcomes in this population. It is suggested that a mean change of 2.09 in pain interference, as measured by the Brief Pain Inventory (BPI), could be considered acceptable to patients. Currently data is unavailable for changes in pain acceptance.

79 patients (48%) reported an improvement.
Complete 3 month data was available for 164 patients who received treatment.
Mean changes on the BPI in the improved cohorts of the PMP were 2.2
which mirrors the acceptable change.
Despite moderate to large effect sizes post treatment,
less than 50% of patients reported that these changes were acceptable.
Patients may require more detailed information about expected outcomes
following pain management programmes, as part of the informed consent process.

Approach

A battery of validated questionnaires were completed by patients attending a 36 hour (standard) interdisciplinary pain management programme at pre-treatment and three months post rehabilitation, between 2015 - 2017. The programme was based on the Acceptance and Commitment Therapy psychological model, with emphasis on enhancing psychological flexibility. The percentage of patients that scored between 5 and 7 (improved) on the Global Impression of Change Score was calculated. Pre and post mean and standard deviations (SD) were calculated on the Brief Pain Inventory - Interference Scale (BPI), Chronic Pain Acceptance Questionnaire (CPAQ-8), Generalised Anxiety Scale (GAD-7), Patient Health Questionnaire (PHQ-9) and the Tampa Scale of Kinesiophobia (TSK). Effect sizes were calculated, using a correlation co-efficient for inter-related measures.

Outcomes

Complete 3 month data was available for 164 patients who received treatment. 79 patients (48%) reported an improvement.

Mean pre-post changes (SD) in the improved / complete cohort were:

  • PHQ-9 13.5 (5.6) - 10.1 (6) / 13.9 (5.8) - 11.0 (6.5)
  • GAD - 7 9.6 (5.7) - 6.8 (5) / 10.3 (5.8) - 7.5 (5.4)
  • BPI 7.3 (1.7) - 5.1 (2.2) / 7.5 (1.9) - 5.4 (2.4)
  • TSK 37.5 (9.4) - 31.2 (9.4) / 38.4 99.4) - 33.2 (10.1)
  • CPAQ 19.6 (8.9) - 24.5 (9.4) / 18.8 (8.2) - 23.2 (9)

Effect sizes in the improved / complete cohort for the PMP were:

  • PHQ-9 (0.7 / 0.5)
  • GAD -7 (0.6 / 0.5),
  • BPI (1.2 / 0.9),
  • TSK (0.8 / 0.5),
  • CPAQ (0.8 / 0.5)

Mean changes on the BPI in the improved cohorts of the PMP were 2.2 which mirrors the acceptable change. Although effect sizes in the total cohorts were generally moderate to large, less than 50% of patients considered these changes as acceptable.

Implications

Patients perceptions of treatment needs to be explored at assessment so that they can make informed decisions about their care. An introductory session has been implemented for all patients attending the pain management programme which describes the programme in greater detail and any potential benefits.

Top three learning points

  1. Despite moderate to large effect sizes post treatment, less than 50% of patients reported that these changes were acceptable.
  2. Reductions in the BPI (suggestive of decreased pain interference)  were of greater magnitude than those reported in the National Pain Audit.
  3. Patients may require more detailed information about expected outcomes following pain management programmes, as part of the informed consent process.

Fund acknowledgements

Not applicable. 

Additional notes

This work was presented at Physiotherapy UK 2019

Please see the attached Innovations poster below. 

 

For further information about this work please contact Leila Heelas