Research Article Open Access

Time Clustering of the Occurrence of Sleep Apnea

Nur Zakiah Mohd Saat1
  • 1 Department of Biomedical Science, Faculty of Allied Health Science, University Kebangsaan Malaysia, Kuala Lumpur, Malaysia


Problem statement: In this study, the inequality of apnea rates during sleep was investigated. Approach: This study used a database comprising 13 patients with apnea problems. The data was extracted from the MIT-BIH database. The Lorenz curve and Gini index were used to determine the inequality of apnea rates. In order to test for cluster, random or regular patterns of apnea, an index of runs was used. Results: The Lorenz curve showed that the distribution of apnea events for every 10% period of sleep varied between each patient. The Gini index ranged between 0.148 and 0.614. Most of the patients had a Gini coefficient lower than 0.5. The index of runs was between 0.115 and 0.353, which indicates that most patients had a regular pattern of apnea and that it is not random. Conclusion: The distribution of the apnea is almost equal and most patients have regular patterns of occurrence of apnea.

American Journal of Applied Sciences
Volume 8 No. 11, 2011, 1081-1085


Submitted On: 11 August 2011 Published On: 23 September 2011

How to Cite: Saat, N. Z. M. (2011). Time Clustering of the Occurrence of Sleep Apnea. American Journal of Applied Sciences, 8(11), 1081-1085.

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  • Apnea
  • gini index
  • lorenz
  • inequality
  • run index