Assessment of the Minimum Clinically Important Difference in the Timed Up and Go Test After Surgery for Lumbar Degenerative Disc Disease

Neurosurgery. 2017 Mar 1;80(3):380-385. doi: 10.1227/NEU.0000000000001320.


Background: The Timed Up and Go Test (TUG Test) has previously been described as a reliable tool to evaluate objective functional impairment in patients with degenerative disc disease.

Objective: The aim of this study was to assess the minimum clinically important difference (MCID) of the TUG Test.

Methods: The TUG Test (measured in seconds) was correlated with validated patient-reported outcome measures (PROs) of pain intensity (Visual Analog Scale for back and leg pain), functional impairment (Oswestry Disability Index, Roland Morris Disability Index), and health-related quality of life measures (Short Form-12 and EuroQol 5D). Three established methods were used to establish anchor-based MCID values using responders of the following PROs (Visual Analog Scale back and leg pain, Oswestry Disability Index, Roland Morris Disability Index, EuroQol 5D index, and Short Form-12 Physical Component Summary) as anchors: (1) average change, (2) minimum detectable change, and (3) change difference approach.

Results: One hundred patients with a mean ± SD age of 56.2 ± 16.1 years, 57 (57%) male, 45 patients undergoing microdiscectomy, 35 undergoing lumbar decompression, and 20 undergoing fusion surgery were studied. The 3 MCID computation methods revealed a range of MCID values according to the PRO used from 0.9 s (Oswestry Disability Index based on the change difference approach) to 6.0 s (EuroQol 5D index based on the minimum detectable change approach), with a mean MCID of 3.4 s for all measured PROs.

Conclusion: The MCID for the TUG Test time is highly variable depending on the computation technique used. The average TUG Test MCID was 3.4 s using all 3 methods and all anchors.

Keywords: Degenerative disc disease; Low back pain; Lumbar spine surgery; MCID; Objective outcome measurement; Postoperative outcome; Timed Up and Go Test.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Decompression, Surgical*
  • Disability Evaluation*
  • Disabled Persons
  • Diskectomy*
  • Female
  • Humans
  • Intervertebral Disc Degeneration / surgery*
  • Lumbar Vertebrae / surgery
  • Male
  • Middle Aged
  • Pain Measurement / methods
  • Quality of Life*
  • Treatment Outcome
  • Visual Analog Scale