Interrater reliability of Engel, International League Against Epilepsy, and McHugh seizure outcome classifications following vagus nerve stimulator implantation

Clinical article

Restricted access

Object

Interrater reliability as measured by the kappa (κ) statistic is a widely used and valuable tool to measure the robustness of a scoring system. Seizure frequency reduction is a central outcome measure following vagus nerve stimulation (VNS). A specific VNS scoring system has been proposed by McHugh, but its interrater reliability has not been tested. The authors assessed its interrater reliability and compared it with that of the Engel and International League Against Epilepsy (ILAE) systems.

Methods

Using the Engel, ILAE, and McHugh scoring systems, 3 observers independently rated the medical records of children who had undergone vagus nerve stimulator implantation between January 2001 and April 2011 at the Southampton University Hospital. The interrater agreements were then calculated using the κ statistic.

Results

Interrater reliability for the McHugh scale (κ0.693) was very good and was superior to those of the Engel (κ0.464) and ILAE (κ0.491) systems for assessing outcome in patients undergoing VNS.

Conclusions

The authors recommend considering the McHugh scoring system when assessing outcomes following VNS.

Abbreviations used in this paper:ILAE = International League Against Epilepsy; VNS = vagus nerve stimulation.

Article Information

Address correspondence to: Fenella J. Kirkham, F.R.C.P.C.H., Department of Child Health, Southampton General Hospital, Southampton, United Kingdom. email: fk@soton.ac.uk.

Please include this information when citing this paper: published online July 20, 2012; DOI: 10.3171/2012.6.PEDS11424.

© AANS, except where prohibited by US copyright law.

Headings

References

  • 1

    Altman DG: Practical Statistics for Medical Research LondonChapman and Hall1990

  • 2

    Burakgazi AZBurakgazi-Dalkilic ECaputy AJPotolicchio SJ: The correlation between vagus nerve stimulation efficacy and partial onset epilepsies. J Clin Neurophysiol 28:3803832011

    • Search Google Scholar
    • Export Citation
  • 3

    Cohen J: A coefficient of agreement for nominal scales. Educ Psychol Meas 20:37461960

  • 4

    Cramer JABen Menachem EFrench J: Review of treatment options for refractory epilepsy: new medications and vagal nerve stimulation. Epilepsy Res 47:17252001

    • Search Google Scholar
    • Export Citation
  • 5

    Durnford AJRodgers WKirkham FJMullee MAWhitney APrevett M: Very good inter-rater reliability of Engel and ILAE epilepsy surgery outcome classifications in a series of 76 patients. Seizure 20:8098122011

    • Search Google Scholar
    • Export Citation
  • 6

    Engel J JrVan Ness PCRasmussen TBOjemann LMOutcome with respect to epileptic seizures. Engel J Jr: Surgical Treatment of the Epilepsies ed 2New YorkRaven Press1993. 609621

    • Search Google Scholar
    • Export Citation
  • 7

    Englot DJChang EFAuguste KI: Vagus nerve stimulation for epilepsy: a meta-analysis of efficacy and predictors of response. A review. J Neurosurg 115:124812552011

    • Search Google Scholar
    • Export Citation
  • 8

    Franzoni EGentile VColonnelli MCBrunetto DCecconi IIero L: VNS in drug resistant epilepsy: preliminary report on a small group of patients. Ital J Pediatr 36:302010

    • Search Google Scholar
    • Export Citation
  • 9

    Kabir SMRajaraman CRittey CZaki HSKemeny AAMcMullan J: Vagus nerve stimulation in children with intractable epilepsy: indications, complications and outcome. Childs Nerv Syst 25:109711002009

    • Search Google Scholar
    • Export Citation
  • 10

    McHugh JCSingh HWPhillips JMurphy KDoherty CPDelanty N: Outcome measurement after vagal nerve stimulation therapy: proposal of a new classification. Epilepsia 48:3753782007

    • Search Google Scholar
    • Export Citation
  • 11

    Mikati MAAtaya NFEl-Ferezli JCBaghdadi TSTurkmani AHComair YG: Quality of life after vagal nerve stimulator insertion. Epileptic Disord 11:67742009

    • Search Google Scholar
    • Export Citation
  • 12

    Wieser HGBlume WTFish DGoldensohn EHufnagel AKing D: ILAE Commission Report. Proposal for a new classification of outcome with respect to epileptic seizures following epilepsy surgery. Epilepsia 42:2822862001

    • Search Google Scholar
    • Export Citation
  • 13

    Wieser HGOrtega MFriedman AYonekawa Y: Long-term seizure outcomes following amygdalohippocampectomy. J Neurosurg 98:7517632003

    • Search Google Scholar
    • Export Citation

TrendMD

Metrics

Metrics

All Time Past Year Past 30 Days
Abstract Views 183 183 24
Full Text Views 52 50 0
PDF Downloads 127 115 0
EPUB Downloads 0 0 0

PubMed

Google Scholar