Retiability　Improvement　and　Economic　Evaluation　of　a　Health　Examination Using　the　Schmidt　Orthogonalization　Method

Abstract

The　objective　of　this　study　is　to　improve　the　reliability　of　the　final　diagnosis　for a　health　examination.　For　this　type　of　study,　the　inverse　matrix　of　a　correlation matrix　is　calculated,　followed　by　the　use　of　an　orthogonal　array　to　select　the contributing　variables　(also　called　items).　In　this　study　however,　the　Schmidt orthogonalization　method　was　used　to　select　the　important　variables　for reliability　improvement　and　cost　reduction.　As　a　result,　the　Signal-to-Noise　ratio increased　by　12.6　db　after　reducing　the　number　of　variables　from　141　to　79. Naturally,　the　reliability　of　diagnosis　was　improved.　Moreover,　the　Loss Function　was　used　for　its　economic　evaluation.