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Published on: October 8, 2012
Low inter-examiner agreement of the Friedman staging system indicating limited value in patient selection
Joar Sundman1,2, Johan Fehrm3,4, Danielle Friberg5
1Department of Clinical Science, Intervention and Technology, Karolinska institutet, 171 77, Stockholm, Sweden. joar.sundman@gmail.com.
Purpose:
The Friedman staging system is a clinical method for selecting patients with obstructive sleep apnoea who are likely to benefit from uvulopalatopharyngoplasty. The objective of this study was to evaluate the system by determining its inter-examiner agreement.
Methods:
Twelve patients with obstructive sleep apnoea were examined by 14 doctors. The Friedman stage was derived from tonsil size and tongue position, and a Cohen's kappa analysis was performed to assess inter-examiner agreement.
Results:
One hundred and sixty-eight ratings were performed. The median kappa for tongue position was 0.32 (first and third quartiles: 0.21 and 0.44) and was 0.62 (0.50 and 0.63) for tonsil size. The median kappa for the Friedman stage was 0.38 (0.24 and 0.55), which corresponds to only a slight or fair agreement.
Conclusion:
The Friedman staging system demonstrated a low inter-examiner agreement, indicating that the system is an uncertain method for selecting patients for uvulopalatopharyngoplasty.
Level Of Evidence:
2B.
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