Sample Size Calculation For Research Studies In Ophthalmology
نویسنده
چکیده
S size is a crucial component of research design. More often researchers want sample size to be justified on non statistical grounds. For example, a researcher may say that I could get only these many cases in the specified time period so as a statistician do something to make the study valid in spite of whatever sample size I have used. Similarly, financial constraint is sometimes cited an excuse for not having attained a given sample size. Others view sample size as a biggest hurdle in their conduct of a methodologically correct research. So let us simplify the issue of sample size once forever.
منابع مشابه
Sample size in studies on diagnostic accuracy in ophthalmology: a literature survey.
AIM To assess the sample sizes used in studies on diagnostic accuracy in ophthalmology. Design and sources: A survey literature published in 2005. METHODS The frequency of reporting calculations of sample sizes and the samples' sizes were extracted from the published literature. A manual search of five leading clinical journals in ophthalmology with the highest impact (Investigative Ophthalmo...
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