Article

A successful outcome after lumbar discectomy indicates a
substantial improvement. To use the cutoffs for minimal clinically important
difference (MCID) as success criteria has a large potential bias, simply because
it is difficult to classify patients who report that they are "moderately
improved". We propose that the criteria for success should be defined by those
who report that they are "completely recovered" or "much better". Methods: A cohort of 692 patients were operated for lumbar disc herniation and followed for
one year in the Norwegian Registry for Spine Surgery.
The global perceived scale
of change was used as an external criterion, and success was defined as those who
reported that they were "completely recovered" or "much better". Criteria for
success for each of (1) the Oswestry disability index (ODI; score range 0-100
where 0 = no disability), (2) the numerical pain scale (NRS; range 0-10 where 0 =
no pain) for back and leg pain, and (3) the Euroqol
(EQ-5D; -0.6 to 1 where 1 =
perfect health) were estimated by defining the optimal cutoff point on receiver
operating characteristic curves. RESULTS: The cutoff values for success for the
mean change scores were 20 (ODI), 2.5 (NRS back), 3.5 (NRS leg), and 0.30
(EQ-5D). According to the cutoff estimates, the proportions of successful
outcomes were 66% for the ODI and 67% for the NRS leg pain scale. INTERPRETATION:
The sensitivity/specificity values for the ODI and leg pain were acceptable,
whereas they were very low for the EQ-5D. The cutoffs for success can be used as
benchmarks when comparing data from different surgical units.

Langue : ANGLAIS