Study on workloads of human care worker with the introduction of IT system - the characteristics of work loads by observational research and the suggestions for KAIZEN

The purpose of this study was to clarify the characteristic of workloads on human care worker with the introduction of IT system, and suggested the support measures for KAIZEN in Japan. The investigation method is workflow line and hearing with a focus on work observation. The objects were 8 human care workers of the acute hospital that introduced an electronic system. By the introduction of the electronic chart, the nurse station sojourn time decreased, sickroom sojourn time increased, and time about direct nursing care to a patient increased. In addition, access to patient information became easy, and the offer of the health care service based on correct information came to be possible in real time. By The point of workflow line, it was effect that moving lengths decreased in order to install the electronic chart in patients' rooms. Though, it was a problem that it hasn't formed where to place the instruments such as sphygmomanometer, clinical thermometer and others.     

Development of the workflow kine systems for support on KAIZEN

In this paper, we introduce the new workflow line system consisted of the location and image recording, which led to the acquisition of workflow information and the analysis display. From the results of workflow line investigation, we considered the anticipated effects and the problems on KAIZEN. Workflow line information included the location information and action contents information. These technologies suggest the viewpoints to help improvement, for example, exclusion of useless movement, the redesign of layout and the review of work procedure. Manufacturing factory, it was clear that there was much movement from the standard operation place and accumulation residence time. The following was shown as a result of this investigation, to be concrete, the efficient layout was suggested by this system. In the case of the hospital, similarly, it is pointed out that the workflow has the problem of layout and setup operations based on the effective movement pattern of the experts. This system could adapt to routine work, including as well as non-routine work. By the development of this system which can fit and adapt to industrial diversification, more effective "visual management" (visualization of work) is expected in the future.     

Estimation of Benchmark Dose of Lifetime Cadmium Intake for Adverse Renal Effects Using Hybrid Approach in Inhabitants of an Environmentally Exposed River Basin in Japan

The aim of this study is to estimate the reference level of lifetime cadmium intake (LCd) as the benchmark doses (BMDs) and their 95% lower confidence limits (BMDLs) for various renal effects by applying a hybrid approach. The participants comprised 3,013 (1,362 men and 1,651 women) and 278 (129 men and 149 women) inhabitants of the Cd‐polluted and nonpolluted areas, respectively, in the environmentally exposed Kakehashi River basin. Glucose, protein, aminonitrogen, metallothionein, and β₂‐microglobulin in urine were measured as indicators of renal dysfunction. The BMD and BMDL that corresponded to an additional risk of 5% were calculated with background risk at zero exposure set at 5%. The obtained BMDLs of LCd were 3.7 g (glucose), 3.2 g (protein), 3.7 g (aminonitrogen), 1.7 g (metallothionein), and 1.8 g (β₂‐microglobulin) in men and 2.9 g (glucose), 2.5 g (protein), 2.0 g (aminonitrogen), 1.6 g (metallothionein), and 1.3 g (β₂‐microglobulin) in women. The lowest BMDL was 1.7 g (metallothionein) and 1.3 g (β₂‐microglobulin) in men and women, respectively. The lowest BMDL of LCd (1.3 g) was somewhat lower than the representative threshold LCd (2.0 g) calculated in the previous studies. The obtained BMDLs may contribute to further discussion on the health risk assessment of cadmium exposure.     

Distribution and density functions of the feasible generalized ridge regression estimator

In this paper, we derive the distribution and density functions of the feasible generalized ridge regression (GRR) estimator. It is shown that when the absolute value of a regression coefficient is close to zero, the distribution of the feasible GRR estimator is bimodal and has thinner tails than that of the OLS estimator.     

On small sample properties of the mixed regression predictor under misspecification

This paper relaxes the Mittelhammer's (1981) assumption that the value of the true variance is known in the mixed regression model and examines the small sample, properties of the feasible mixed regression predictor under misspecification. The paper shows that the feasible mixed regression predictor is not always superior to the ordinary least squares predictor in terms of the weak mean square error when there exist omitted variables in the model. Further it shows that misspecificstion works favorably for the ordinary least squares predictor.     

On the use of the Box-Cox transformation in a linear regression with a lagged dependent variable

In this paper, we show a maximum likelihood estimation procedure in the Box-Cox model when a lagged dependent variable is included among explanatory variables and the first observation of the dependent variable is random. It is shown in a numerical example that a test of a coefficientof the lagged dependent variable is sensitive to whether the first observation of the dependentvariable is random or not.     

PMSE performance of two different types of preliminary test estimators under a multivariate t error term

Abstract

In this paper, assuming that the error terms follow a multivariate t distribution, we derive the exact formula for the predictive mean squared error (PMSE) of two different types of pretest estimators. It is shown analytically that one of the pretest estimator dominates the SR estimator if a critical value of the pretest is chosen appropriately. Also, we compare the PMSE of the pretest estimators with the MMSE, AMMSE, SR and PSR estimators by numerical evaluations. Our results show that the pretest estimators dominate the OLS estimator for all combinations when the degrees of freedom is not more than 5.     

The exact risk performance of a pre-test estimator in a heteroskedastic linear regression model under the balanced loss function

We examine the risk of a pre-test estimator for regression coefficients after a pre-test for homoskedasticity under the Balanced Loss Function (BLF). We show analytically that the two stage Aitken estimator is dominated by the pre-test estimator with the critical value of unity, even if the BLF is used. We also show numerically that both the two stage Aitken estimator and the pre-test estimator can be dominated by the ordinary least squares estimator when “goodness of fit” is regarded as more important than precision of estimation.     

Sleep disturbance as a clinical sign for severe hypogonadism: efficacy of testosterone replacement therapy on sleep disturbance among hypogonadal men without obstructive sleep apnea

Objective: The present subanalysis of the EARTH study investigates the effects of one year testosterone replacement therapy (TRT) on sleep disturbance among hypogonadal men without obstructive sleep apnea.

Methods: Sleep disturbance was defined as three or more points in question 4 of the aging males symptoms (AMS) questionnaire. All participants completed the AMS scale, International Prostatic Symptoms Score (IPSS), Sexual Health Inventory for Men (SHIM) and Short Form 36 (SF-36) health survey at baseline and after 12?months. Sexual symptoms were also evaluated based on three AMS subscores (Q15, 16 and 17).

Results: We identified 100 patients with sleep disturbance, of whom 48 (24 each in the TRT and control groups) were ultimately included for analysis. All SF-36 categories , AMS scale, IPSS and SHIM score subdomains were significantly worse in patients with sleep disturbance than in those without disturbance. Statistically significant differences in sleep disturbance, erectile symptoms, sexual desire and some domains of the SF-36 were observed between the TRT and control groups after 12?months.

Conclusion: Sleep disturbance may be one of the clinical signs for severe hypogonadism. Moreover, TRT improved sleep conditions, sexual function and quality of life among hypogonadal men with sleep disturbance.     

The exact distribution and density functions of a pre-test estimator of the error variance in a linear regression model with proxy variables

We consider a linear regression model when some independent variables are unobservable, but proxy variables are available instead of them. We derive the distribution and density functions of a pre-test estimator of the error variance after a pre-test for the null hypothesis that the coefficients for the unobservable variables are zeros. Based on the density function, we show that when the critical value of the pre-test is unity, the coverage probability in the interval estimation of the error variance is maximum.