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PubMed1991

Inaccuracy of height information on driver's licenses.

Height is an important variable in identification. In cases involving decreased individuals, height is measured directly on the corpse or estimated from the skeleton. This postmortem measurement or estimation is then compared with antemortem records, usually the driver's license. The accuracy of the license information, however, has been questioned. To assess the accuracy of driver's license information, volunteers' statures were measured, and then these figures were compared with those printed on the subjects' licenses. Even in our comparatively young, well-educated sample, the license height was significantly greater than the measured height. Some inaccuracies may be caused by failure to update license information when new licenses are issued, but some inaccuracies may be from personal deception. The implications of these results for forensic anthropology cases are discussed.

Analysis of Variance↗
PubMed1991

Robust estimation of the variance in moment methods for extra-binomial and extra-Poisson variation.

When faced with data in the form of overdispersed counts or proportions, moment methods allow consistent parameter estimation when only the form of the mean and variance is specified. If the variance form is misspecified, these methods still yield consistent parameter estimates, though with lower efficiency, and the variances of the estimates will be inconsistent. A variance correction is available that yields consistent variance estimates in these circumstances. The asymptotic and small-sample efficiencies of this correction are calculated, and its performance under variance misspecification is studied. A group-randomized breast self-examination prevention study that is now underway serves as a focal point for the study of these properties. The use of the variance correction in modelling is illustrated on a teratology data set.

Analysis of Variance↗
PubMed1991

Modelling sub-binomial variation in the frequency of sex combinations in litters of pigs.

In some samples of pig litters, the number of males per litter exhibits significant sub-binomial dispersion: there are fewer unisexual and more "sex-balanced" litters than expected under a binomial model. It is argued here that the explanation is that the sex of zygotes may be subject to hormonal control with the consequence that, within a litter, the zygotes do not all have the same probability of being male. This variation in probability is approximated by a quadratic function of the time during oestrus that a zygote is formed so as to parallel the variation in maternal hormone levels. Other explanations are examined briefly, but each seems to have serious weaknesses.

Analysis of Variance↗
PubMedDate not supplied

A study of children's taste and visual preferences in dentifrices.

Variables and gimmicks can make choosing a dentifrice for a child complicated. Various flavors, colors, shapes, consistency, labelling, and type of dispensers provide a constellation of choices for the consumer. This study sought to determine whether children actually prefer the dentifrices designed for them. Visually the child-oriented products were preferred; modern containers were preferred over the traditional. In terms of taste, however, "child-flavored" dentifrices were not preferred over the regular flavor of the same brand, when one is tasted after the other.

Binomial Distribution↗
PubMed1991

Health promotion behaviors of private practice dental hygienists.

Today, there is increased emphasis in oral healthcare on health promotion and disease prevention. This is consistent with the focus of the dental hygiene profession. The purpose of this study was to investigate the health promotion behaviors of private practice dental hygienists within the ADHA District X region (Colorado, Montana, Utah, Wyoming). Statistical analysis procedures (frequencies, tests of statistical significance, and factor analysis) were performed on the questionnaire responses of 817 respondents who were employed in private practice settings. The results indicated that most respondents spent approximately five to 10 minutes on oral hygiene instruction (OHI) during a prophylaxis appointment, and focused on a variety of "traditional instructional" activities (e.g., discussing brushing and flossing, plaque control, caries, and periodontal disease). The majority of the respondents were satisfied with the amount of time they spent on OHI. When asked what factors limited the amount of time spent on OHI, the respondents most often cited "lack of interest on the part of the patient." Most respondents indicated there was no separate fee charged for OHI, even if separate OHI appointments were scheduled. The factor analysis indicated that some low-frequency behaviors (e.g., use of disclosants) were related more strongly to the concept of health promotion than were some high-frequency behaviors (e.g., use of a periodontal probe). The results of this study indicate that although health promotion services are provided frequently by dental hygienists, these services may not be provided consistently in the most effective way. Future research efforts could investigate the health promotion behaviors of private practice hygienists across the nation with a revised questionnaire to determine more adequately the status of these behaviors.

Analysis of Variance↗
PubMed1991

Poisson approximation to a negative binomial process in the surveillance of rare health events.

The Poisson approximation to a negative binomial process is evaluated regarding the surveillance of rare health events in the framework of the "Sets" scheme. This scheme defines an alarm in terms of "distance" between consecutive events of interest. The system's parameters are determined by minimizing the expected delay for an alarm when a given increase in the event rate has occurred, subject to a restriction on the rate of false alarms. It is shown that the main consequence of the Poisson approximation lies in an increase of the false alarm probability with respect to the assigned one, whilst influence on the expected delay for a true alarm is lower. It is, however, found that over a large range of practical instances, the Poisson assumption provides a reasonable description of the negative binomial process.

Binomial Distribution↗
PubMed1990

[Doppler echocardiographic evaluation of right heart pressure in children with ventricular septal defect].

Thirty seven children with ventricular septal defects (VSD) alone or associated with other malformations were examined by Doppler echocardiography to evaluate systolic right ventricular pressure (SRVP) non-invasively. All patients underwent cardiac catheterisation within 48 hours of the Doppler estimation. The maximum interventricular pressure gradient could be assessed in 32 patients (86%) from the recording of the maximum velocity of the VSD jet using the simplified Bernoulli formula. The SRVP was calculated by subtracting the maximum interventricular pressure gradient from the systolic blood pressure measured by sphygmomanometry. The SRVP estimated by continuous wave Doppler ranged from 24 to 108 mmHg (mean: 60 mmHg) compared with 20 to 109 mmHg (mean: 64 mmHg) at catheterisation. Two types of correlation were sought: 1) between the maximum interventricular pressure gradient measured by Doppler echo and the peak-to-peak LV-RV pressure gradient (r = 0.95; SD = 6 mmHg; Y = 1.03 x X + 1.3); 2) and between the SRVP measured by Doppler and by catheterisation (r = 0.94; SD = 6 mmHg; Y = 1.06 x X + 7.7). These results show that the maximum velocity of the interventricular jet and thereby the SRVP may be accurately measured by Doppler echocardiography in the majority of patients with VSD.

Adolescent↗
PubMed1990

Statistical analysis of the genotoxicity study results.

One of the methods used in the genotoxicity study of chemical compounds is micronucleus test in vivo. There is no clear consensus as to which statistical method is most suitable to study the frequency of occurrence of micronucleated polychromatic erythrocytes. This paper proposes two statistical tests: approximate normal test and conditional binomial test (Kastenbaum & Bowman).

Analysis of Variance↗
PubMed1990

[Efficacy of influenza vaccination--the detection of a seeming efficacy].

In Japan, influenza vaccination has been offered to schoolchildren as a collective preventive program with parents given the right to participate or not participate in this program since 1987. Literature on the efficacy of influenza vaccination including the research report by the Ministry of Health and Welfare (1987) which proposed the continuation of the collective immunization program were examined. In almost all of the papers supportive of vaccination, approaches by which the final conclusions of the efficacy of vaccination were obtained have been found to be scientifically marginal in design and analysis. In order to further investigate these problems, a reanalysis of the data from recent studies by Satomi and Mori (1989) was conducted. A significant efficacy of the influenza vaccination could not be detected from this analysis, strongly suggesting that what appeared to be an efficacy in many papers may have been produced as a result of the confounding by the "healthiness" of the study population.

Binomial Distribution↗
PubMed1990

Approximate interval estimation of the difference in binomial parameters: correction for skewness and extension to multiple tables.

Recently, Beal (1987, Biometrics 43, 941-950) found Mee's modification of Anbar's approximate interval estimation for the difference in binomial parameters to be a good choice in small sample sizes. As this method can be derived from the score theory of Bartlett, it is easily corrected for skewness. Exact numerical evaluation shows that this correction is not as important for this case as for the ratio of binomial parameters (Gart and Nam, 1988, Biometrics 44, 323-338). The score theory is also used to extend this method to the stratified or multiple-table case. Thus, good approximate interval estimates for differences, ratios, and odds ratios of binomial parameters can all be derived from the same general theory.

Binomial Distribution↗
PubMedDate not supplied

[Use of NSAIDS in dentistry: double blind controlled study of Diflunisal versus ASA].

As a conclusion to the results obtained during our studies, we can say that both drugs provided fast and accurate antalgic anti-inflammatory characteristics. Diflunisal has however shown a slightly more powerful and larger lasting antalgic action which provides a higher tolerance level than the drug which was used as a comparison.

Adolescent↗
PubMed1990

Declining serum cholesterol levels prior to diagnosis of colon cancer. A time-trend, case-control study.

We report the results of a 10-year, time-trend, case-control study in which serum cholesterol level was determined at several points in time preceding the diagnosis of colon cancer in a population of individuals who sought general checkups at an ambulatory care screening facility. Each of the 69 patients with colon cancer (32 men and 37 women) was matched with a control patient who was randomly selected. At the time of diagnosis, the patients with colon cancer had significantly lower serum cholesterol values than control patients (5.56 +/- 0.31 mmol/L [SEM] vs 6.47 +/- 0.34 mmol/L). This difference did not vary with sex or Dukes' stage of the cancer. The percent of matched pairs in which the cancer patient had a lower serum cholesterol level increased from 42% at 10 years prior to cancer diagnosis to 77% at diagnosis. The ratio of serum cholesterol at each period to the level at time of diagnosis demonstrated an average decline of 13% during the 10 years prior to diagnosis for case patients vs an average rise of 2% in the same period for control patients. We conclude that individuals in whom colorectal cancer develops share the same level of serum cholesterol as the general population initially, but during the 10 years preceding the cancer demonstrate a decline in serum cholesterol level that is opposite to the rising level seen with age in the general population.

Aged↗
PubMed1990

[Small group tests against Victor types and syndromes].

Victor's recent alternative model for configural frequency analysis (CFA) estimates expected frequencies for hypothesized type cells from a quasi-independence log-linear model. The tests against types use chi-square components. A comparison with the binomial test shows that the standard errors of the chi-square components can be too small when samples are small. From simulation results formulas for the standard error that consider sample size are derived. The paper shows that these formulas do not suggest nonconservative decisions. Empirical data examples from legasthenia research illustrate the methodological findings.

Analysis of Variance↗
PubMedDate not supplied

Accuracy of the simplified Bernoulli relationship in measuring pressure gradients across stenosis.

In order to test the validity of the modified Bernoulli equation in predicting pressure gradients across stenotic regions, we have constructed an in-vitro model and studied the influence of the length and of the severity of the stenosis. Under physiological conditions, simultaneous pressure gradients are estimated by both Doppler and direct pressure manometer techniques. Measurements of the pressure gradients (in the range 10-150 mmHg) by the two techniques show that the Doppler estimation using the modified Bernoulli equation underestimated the pressure transducer gradient measurements for every length of stenosis, this underestimation being greater than 45% for very severe stenosis.

Arterial Occlusive Diseases↗
PubMed1988

Controlled breeding in the Asiatic buffalo (Bubalus bubalis).

Recent developments in exogenous hormone therapy to control and facilitate breeding in domestic buffalo cows (B. bubalis) are reviewed. Oestrus in domestic animals was synchronized satisfactorily during the normal breeding season by both of the standard treatments with prostaglandins or progestagens initially developed for use in Bos taurus cattle. Anoestrous cyclic cows treated with prostaglandin showed synchronized oestrus and conception rates similar to those recorded in normal cyclic animals, though the responses may have depended to some extent on increased intensity of observation of oestrus. Seasonally acyclic animals treated with progestagens and pregnant mare serum gonadotrophin also showed synchronized oestrus and conception rates equivalent to those recorded in cyclic animals, but these observations did not include prepubertal heifers or cows in the early stages of post-partum anoestrus. Controlled breeding did not overcome a general problem of low conception rates at spontaneous oestrus. Further investigations of controlled breeding should incorporate other management strategies, such as better feeding and reduced heat stress, which are known also to improve buffalo reproduction.

Animals↗