105 CHAPTER SIX
106 6.3 LIMITATION OF THE STUDY
QT interval and dispersion can only be measured accurately in good quality ECG recordings, this study made efforts to exclude ECGs of poor quality.
Some limitation in QT measurement occurred as result of distortion of the ECG tracings from vibration of the ringing phone and this made measurement difficult.
In frankly abnormal ECGs, QT interval and dispersion measurement were technically difficult.
M- Mode directed cardiac chamber measurements using leading edge to leading edge method may give rise to inaccurate measurements in cases of regional abnormalities and may also result in magnification of small errors in measurements with consequent overestimation in LV mass.
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122 APPENDIX I INFORMATION SHEET
Title of study: The effect of electromagnetic fields emitted from mobile phones on QT interval and dispersion among hypertensive patients.
Researcher: Dr Oluwole A.O, Cardiology Unit, Dept. of Medicine, OOUTH, Sagamu.
Background: Many people now use and possess GSM handsets (mobile phones) to enable them communicate with other phone users. Some preferred to keep their handset in their chest pockets close to the heart while others keep theirs in the trousers’ pockets.
The mobile phone releases some form of energy to enable it connect with other phones.
This study is being done to determine whether the energy released from mobile phones have any effect on the heart and also to determine whether this possible effect differs based on phone location.
Any risk involved? According to the World Health Organization (WHO), the energy released from mobile phone pose no health risk to humans. There is no risk to your life if you agree to participate in the study.
What is involved? You will be expected to answer few questions about your health and phone habits, get examined and have some ECGs (tracings of the heart activity) done with the phone on your chest and at the level of your hip.
Confidentiality: Your identity and participation in this study will be treated as confidential.
The information provided and your result will not be disclosed to any third party other than the purpose of this medical research.