Sample size requirements for case-control study designs

Sample size requirements for case-control study designs: correction

1. Add the phrase "within each stratum" to the last sentence in the section preceding the section titled "Interac-tion". In the PDF version this is at line 5 in the first column of page 4. The whole sentence should read: "Con-sequently, it is not required that F controls be linked with each case, only that the total number of controls be F times the total number of cases within each stratum." 2...

Sample size requirements for case-control study designs

BACKGROUND Published formulas for case-control designs provide sample sizes required to determine that a given disease-exposure odds ratio is significantly different from one, adjusting for a potential confounder and possible interaction. RESULTS The formulas are extended from one control per case to F controls per case and adjusted for a potential multi-category confounder in unmatched or ma...

Sample size requirements in case-only designs to detect gene-environment interaction.

With advances in molecular genetic technology, more studies will examine gene-environment interaction in disease etiology. If the primary purpose of the study is to estimate the effect of gene-environment interaction in disease etiology, one can do so without employing controls. The case-only design has been promoted as an efficient and valid method for screening for gene-environment interactio...

Sample Size Requirements for Feedforward Neural Networks

We estimate the number of training samples required to ensure that the performance of a neural network on its training data matches that obtained when fresh data is applied to the network. Existing estimates are higher by orders of magnitude than practice indicates. This work seeks to narrow the gap between theory and practice by transforming the problem into determining the distribution of the...

Main Risk Factors for Ectopic Pregnancy: A Case-Control Study in A Sample of Iranian Women