EUROSPINE's tool of choice for low back pain evaluation

The development of the Core Outcome Measures Index-back (COMI-back) was an attempt to standardize patient-reported outcome measures to a few core items that were recommended by an international group of back pain researchers named the European Spine Study Group. The measure is part of EUROSPINE’s spine tango, an international registry to collect data from patient-reported outcome measures for clinical studies and research.

Although the questionnaire consists of only 6 questions, many dimensions are covered within this outcome measure (pain intensity, back-related function, symptom-specific well-being, general quality of life, social disability and work disability). The COMI-back questionnaire has been used in studies of patients with spinal deformities and lumbar spinal stenosis and has been proved a validated tool for back pain evaluation.


The questionnaire has been developed for low back pain evaluation. For instance, it has recently been used to gain knowledge about patient outcomes after spinal deformity treatment 1 and the surgical treatment of lumbar spinal stenosis 2 3.

Items - Dimensions - Completion time

In the core COMI-back, 1 question consists of 2 numerical rating scales to be answered from 0 to 10 and 5 questions to be answered by selecting 1 of 5 response options.

The EUROSPINE and Deutsche Wirbelsäulengesellschaft versions have 5 additional questions on pain quality and patient satisfaction with the treatment and outcome. The additional questions do not influence the COMI-back score.

The 6 items cover 5 dimensions: pain intensity (back and leg pain), back-related function, symptom-specific well-being, general quality of life and disability (social and work). The patient is asked to answer based on how he or she has felt for the last week, except for the disability dimensions, for which the patient is asked to answer based on how he or she has felt for the last 4 weeks.

There is no information in the literature on completion time. We estimate a time of approximately 5 minutes.

Scoring method

Each dimension receives a subscore. The higher of the 2 pain intensity scores forms the pain intensity dimension subscore. Each response for each of the other 5 questions is scored from 0 to 10:

response 1 (associated with the best possible health status): 0 points

response 2: 2.5 points

response 3: 5 points

response 4: 7.5 points

response 5 (associated with the most health limitations): 10 points

The average of the 2 disability scores forms the disability dimension subscore.
A total COMI score is determined by averaging the 5 dimension scores. There is no information on how to deal with missing data or skipped questions. 4

Scoring example:

Question 1: 5 and 4 points respectively (the higher value of 5 is used for scoring)

Question 2: response 4 (7.5 points)

Question 3: response 2 (2.5 points)

Question 4: response 2 (2.5 points)

Question 5: response 1 (0 points)

Question 6: response 4 (7.5 points)

COMI score: (5+7.5+2.5+2.5+((0+7.5)/2))/5 = 4.25

Score interpretation

The lower the score, the better the patient’s health.

The lowest possible score of 0 points is associated with no loss of health or function and no pain, whereas the maximum score of 10 points represents the most severe back pain and loss of function.

The COMI-back has been validated in several languages 5 6 7 8. An English source document is available on EUROSPINE’s website.
The questionnaire is available in several publications that have developed or validated the COMI-back 4. Versions with additional questions can be obtained on EUROSPINE’s website 9.
The EUROSPINE version is accessible via the spine tango program. Therefore, the user has to be a registered EUROSPINE member, but this is not linked to any registration costs or license fees. 9
The intention of the COMI-back was to create a standardized outcome measure that could improve the comparability of studies. Therefore, the items were scientifically chosen based on meta-analysis of back pain questionnaires and different generic instruments. The administration and completion of the tool are easy and time-saving.
International publications using the COMI-back are rare. Small ceiling and floor effects have been observed. Because of the small number of questions, it has to be assumed that the measure offers a superficial but not a detailed health evaluation, although it has showed good psychometric values in comparison with other low back pain tools. 7

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  1. The Core Outcome Measures Index (COMI) is a responsive instrument for assessing the outcome of treatment for adult spinal deformity.” European Spine Journal 25.8 (2016): 2638-2648.
  2. Röder, Christoph, et al. “Superior outcomes of decompression with an interlaminar dynamic device versus decompression alone in patients with lumbar spinal stenosis and back pain: a cross registry study.” European spine journal 24.10 (2015): 2228-2235.
  3. Munting, Everard, et al. “Patient outcomes after laminotomy, hemilaminectomy, laminectomy and laminectomy with instrumented fusion for spinal canal stenosis: a propensity score-based study from the Spine Tango registry.” European spine journal 24.2 (2015): 358-368.
  4. Mannion, Anne F., et al. “Could less be more when assessing patient-rated outcome in spinal stenosis?.” Spine 40.10 (2015): 710-718.
  5. Mannion, A. F., et al. “The Core Outcome Measures Index (COMI) is a responsive instrument for assessing the outcome of treatment for adult spinal deformity.” European Spine Journal 25.8 (2016): 2638-2648.
  6. Genevay, Stéphane, et al. “Reliability and validity of the cross-culturally adapted French version of the Core Outcome Measures Index (COMI) in patients with low back pain.” European Spine Journal 21.1 (2012): 130-137.
  7. Mannion, Anne F., et al. “Outcome assessment in low back pain: how low can you go?.” European Spine Journal 14.10 (2005): 1014-1026.
  8. Damasceno, L. H. F., et al. “Cross-cultural adaptation and assessment of the reliability and validity of the Core Outcome Measures Index (COMI) for the Brazilian-Portuguese language.” European Spine Journal 21.7 (2012): 1273-1282.