Table 3 Examples of calculation of MCID or CID in pain scores in patients with painful spine conditions
Reference (treatment) | Method | Categories in anchor | Definition of MCID or CID for improvement | MCID or CID a |
|---|---|---|---|---|
Distribution-based approaches | ||||
Carreon 2013 (lumbar fusion surgery) [17] | MDC | N/A—no anchor used | MDC defines the MCID | 1.16 pt—back pain, 1.36 pt—leg pain |
Gum 2013 (lumbar fusion surgery) [18] | MDC | N/A—no anchor used | MDC defines the MCID | 0.20 pt—back pain, 0.23 pt—leg pain |
Anchor-based approaches | ||||
Gum 2013 (lumbar fusion surgery) [18] | ROC—health transition item on SF-36 | Much worse, somewhat worse, about the same, somewhat better, and much better | Change in pain score for patients being “somewhat better” (MCID) | 3.08 pt—back pain, 2.83 pt—leg pain |
Change in pain score for patients being “much better” (CID) | 5.32 pt—back pain, 4.98 pt—leg pain | |||
Carreon 2010 (cervical spine fusion) [19] | ROC—Health transition item of SF-36 | Much better, somewhat better, about the same, somewhat worse, much worse | Distinguish the “somewhat better” from the “about the same” patients (MCID) | 2.5 pt—arm and neck pain |
Copay 2008 (lumbar spine surgery) [20] | Anchor—satisfaction with results scale | Answers: definitively true, mostly true, don’t know, mostly false, or definitively false to the following five items: 1. “I can do the things I thought I would be able to do after surgery”; 2. “I was helped as much as I thought I would be by my surgery”; 3. “My pain was reduced as much as I expected it to be after surgery”; 4. “The benefits of my care outweighed the setbacks it caused me”; 5. “All things considered, I would have the surgery again for the same condition” | Patients classified as “satisfied” and “don’t know” | 1.2 pt—back pain, 1.6 pt—leg pain |
Solberg 2013 (lumbar discectomy) [21] | Anchor—global perceived scale of change | Completely recovered, much improved, slightly improved, no change, slightly worse, much worse, and worse than ever | Patient reporting to be “completely recovered” or “much better” (CID) | 2.5 pt—back pain, 3.5 pt—leg pain |
Parker 2013 (anterior cervical discectomy and fusion) [22] | ROC—NASS | 1) The treatment met my expectations; 2) I did not improve as much as I had hoped, but I would undergo the same treatment for the same outcome; 3) I did not improve as much as I had hoped, and I would not undergo the same treatment for the same outcome; and 4) I am the same or worse than before treatment | Patients with choice 1 classified as responders; choices 2–4 are non-responders (CID) | 4.0 pt—VAS neck pain, 4.0 pt—VAS arm pain |
Combination: NASS anchor + MDCb | 2.6 pt—VAS neck pain, 4.1 pt—VAS arm pain | |||