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PubMed1990

A discriminant analysis of severe alcohol consumption among older persons.

A cross-sectional study among older persons (N = 1034) utilized multivariate stepwise discriminate analysis to determine the predictive value of variables affecting alcohol intake. Fifteen per cent of our study sample was classified as severe drinkers. Alcohol consumption before age 40, smoking, male gender and marital status were predictors of severe drinking. In addition, the unimpaired Older Americans Resource and Services (OARS) objective summary ratings for physical status and activities of daily living (ADL) were associated with severe drinking. Assessing the factors that predict alcohol consumption may help to identify initially those persons at possible risk, lending to heuristic and theoretical alcohol prevention policies among the aged.

Activities of Daily Living↗
PubMed2006

Classification of malignant gliomas by infrared spectroscopic imaging and linear discriminant analysis.

Infrared (IR) spectroscopy provides a sensitive molecular fingerprint for tissue without external markers. Supervised classification models can be trained to identify the tissue type based on the spectroscopic fingerprint. Infrared imaging spectrometers equipped with multi-channel detectors combine the spectral and spatial information. Tissue areas of 4 x 4 mm(2) can be analyzed within a few minutes in the macroscopic imaging mode. An approach is described to apply this methodology to human astrocytic gliomas, which are graded according to their malignancy from one to four. Multiple IR images of three tissue sections from one patient with a malignant glioma are acquired and assigned to the six classes normal brain tissue, astrocytoma grade II, astrocytoma grade III, glioblastoma multiforme grade IV, hemorrhage, and other tissue by a linear discriminant analysis model which was trained by data from a single-channel detector. Before the model is applied here, the spectra are shown to be virtually identical. The first specimen contained approximately 95% malignant glioma regions, that means astrocytoma grade III or glioblastoma. The smaller percentage of 12-34% malignant glioma in the second specimen is consistent with its location at the tumor periphery. The detection of less than 0.2% malignant glioma in the third specimen points to a location outside the tumor. The results were correlated with the cellularity of the tissue which was obtained from the histopathologic gold standard. Potential applications of IR spectroscopic imaging as a rapid tool to complement established diagnostic methods are discussed.

Artificial Intelligence↗
PubMed1990

Sex determination from the hyoid bone by means of discriminant analysis.

Sex diagnosis of skeletal remains represents one of the main problems in the forensic osteological practice. The purpose of the paper was to apply discriminant analysis as the method of its solution--in the set of measurements carried out on the hyoid bone. Classical procedure by R. A. Fisher yielded the set of linear discriminant functions applicable also in cases of injured bones, which is the relatively frequent situation. Information efficiency of the method proved to be quite satisfactory--in case of complete set of all six measurement level of misclassification should not reach over four per cent of the items to diagnose.

Female↗
PubMed1989

[Discriminant analysis concerning the background factors of dental caries prevalence in young child-patients visiting the pedodontic clinic of Ohu University Dental Hospital].

In order to get the appropriate clinical information for dental caries prevention, 38 boys and 30 girls who visited the pedodontic clinic of Ohu University Dental Hospital were surveyed for 3 years, they ranged from 2 to 5 years of age. They had all deciduous teeth and were classified into 4 groups, desirable, light, moderate and severe, on the basis of the longitudinal changes of the dental caries attack patterns, after 1 year and 3 years, which is used at the dental health examination of 3-year old children in Japan. The relationships between the groups and the investigations from documents of their past history, health and usual condition of living at their first visit to the hospital were analysed by means of discriminant analysis of the first class of Hayashi's quantifying theory. The results were as follows: 1. O caries attack patterns at 2 years of age transmitted to all caries attack patterns except B patterns at 3 years, and O caries attack patterns at 3 and 4 years never transmitted to C patterns at 5 years. 2. The desirable group having no change in the caries attack patterns was 64.7%, at 2 to 3 years, but was 25.1% and decreased markedly at 2 to 5 years. The severe group transmitting to C caries attack patterns was 17.7% at 2 to 3 years, but was 42.6% and increased remarkably at 2 to 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗
PubMed2006

Classification of malignant gliomas by infrared spectroscopy and linear discriminant analysis.

Gliomas are the most frequent primary brain tumors. Their malignancies are graded from 1 to 4. Malignant gliomas are astrocytoma grade 3 and glioblastoma grade 4. An IR spectroscopic approach is presented to diagnose brain tissue at the molecular level probing chemical and structural properties without external markers. IR spectroscopic maps were recorded in transmission mode by sequential acquisition of IR spectra. Training spectra of various tissue types are selected from IR spectroscopic maps in accordance with histological assessment of hematoxylin and eosin stained parallel tissue sections. A decrease of the lipid-to-protein ratio in IR spectra is correlated with the malignancy of gliomas. This chemical property is described by the band intensity ratio 2850 to 1655 cm(-1). Two additional molecular descriptors are identified at 1545 cm(-1)/1655 cm(-1) and (1231 + 1450) cm(-1)/1655 cm(-1), which are associated with hemoglobin and collagen, respectively. This metric is used to train a classification model based on linear discriminant analysis. The model is applied to classify normal brain tissue, astrocytoma grade 2, astrocytoma grade 3, glioblastoma, hemorrhage, and leptomeninges in IR spectroscopic maps of cryosections from two glioma patients. As independent test samples, single IR spectra from cryosections of 51 patients are subjected to the classification model. Normal brain tissue is assigned with 100% accuracy; malignant gliomas are assigned with 93% accuracy. The high success rate demonstrates that IR spectroscopy can complement established methods such as histopathology or immunohistochemistry to characterize dried cryosections.

Astrocytoma↗
PubMed1990

Percutaneous transluminal angioplasty for atheromatous renal artery stenosis--blood pressure response and discriminant analysis of outcome predictors.

Percutaneous transluminal angioplasty was performed in 39 consecutive patients with atheromatous renal artery stenosis associated with hypertension. The mean blood pressure before angioplasty was 191/107 mmHg and this had dropped to a mean of 167/90 mmHg at the patient's most recent visit, representing a significant fall in both systolic (p less than 0.01) and diastolic pressures (p less than 0.001). The mean serum creatinine was 166.7 mumol/l before percutaneous transluminal angioplasty and 155.3 mumol/l at the most recent visit (not statistically significant). The mean number of anti-hypertensive drugs fell from 2.4 to 1.9 after percutaneous transluminal angioplasty (p less than 0.05). Three patients (eight per cent) were 'cured' (diastolic blood pressure less than 90 mmHg without medication), 25 (64 per cent) had 'improved' (diastolic blood pressure less than 109 mmHg, with a fall of more than 15 per cent) and 11 (28 per cent) had not improved. Logistic discriminant analysis showed that pre-percutaneous transluminal angioplasty diastolic blood pressure, age, serum creatinine and smoking habit together correctly predicted the outcome of percutaneous transluminal angioplasty in 90 per cent of patients, with four 'false positives' and no 'false negatives'. Ten patients suffered a total of 12 serious complications related to the procedure: one death in acute renal failure, one myocardial infarction, one severe hypotension just after the procedure, one deep vein thrombosis, one episode of transient ischaemia of the toes and seven groin haematomas. Thus percutaneous transluminal angioplasty for atheromatous renal artery stenosis rarely 'cures' hypertension, but improved blood pressure control is often achieved, albeit at the expense of troublesome complications. A prospective, randomized trial is needed to establish whether or not the improvement is due directly to percutaneous transluminal angioplasty.

Age Factors↗
PubMed1994

Predictive value of Müller maneuver, cephalometry and clinical features for the outcome of uvulopalatopharyngoplasty. Evaluation of predictive factors using discriminant analysis in 30 sleep apnea patients.

The success rate of uvulopalatopharyngoplasty (UPPP) in the treatment of obstructive sleep apnea is generally only 50-60%. In order to improve this, various predictive factors for the outcome of UPPP were studied, including the Müller maneuver and cephalometry. Thirty unselected consecutive patients with obstructive sleep apnea (median apnea index (AI) 26 apneas/h, range 5-78) underwent UPPP with standard tonsillectomy except in the case of small tonsils and using CO2 laser for the palatal resection. Polysomnographic control 5 months after surgery showed that 63% of all patients had obtained a reduction in AI > or = 50% including an AI < 20 after surgery. Tonsillectomy had no influence on the outcome. Further, the Müller maneuver did not predict the outcome, whereas cephalometry proved to be of good predictive value. Lowered position of the hyoid bone, increased cranio-cervical angle and shortening of the maxilla length were significantly associated with poor results of UPPP, as were overweight, narrowing of the hypopharynx, the severity of sleep apnea, and hypersomnia. However, in a discriminant analysis containing all these variables, the three cephalometric measurements together with hypersomnia were most closely associated with the outcome of UPPP. A predictive model containing these four variables could correctly classify 83% of the patients in the present study. The model had a false positive rate of 7% in predicting a successful outcome. This indicates that cephalometry is mandatory in the selection of UPPP candidates and that a predictive model containing some or all of the four variables may substantially improve the success rate.

Adult↗
PubMed1983

Discriminating analysis of "in vitro" prostaglandin release by myometrial and luminal sides of the ewe endometrium.

An original perifusion device which allows a discrimination between the 30 mn releases of prostaglandins F2 alpha and E2 by the luminal and the myometrial faces of sheep endometrium is described. Tissue was sampled on day 4, 14, 16 or 17 of the cycle and on day 14 or 17 of pregnancy. Total prostaglandin (PG) release measured with this device was in good agreement with PG's concentrations in media of in vitro endometrium incubations already described. Discrimination analysis of the PGs release by each side of the endometrial tissue during the 30 mn perifusion time revealed that PGF2 alpha concentrations of the perifusion medium issued from the lumen compartment were higher than those of the myometrial compartment in all physiological status where corpus luteum is active (including early pregnancy). Therefore in the ewe, it seems that luteal structure maintenance during early pregnancy is not due, as in the gilt, to a shift in PGF2 alpha secretion towards the uterine lumen.

Animals↗
PubMed1993

Discriminant analysis of symptom pattern and serum antibody titres in humidifier related disease.

BACKGROUND: The heterogeneous patterns of symptoms among factory workers exposed to aerosols from contaminated air humidifiers were analysed to assess the association between specific symptoms and the serum IgG antibody response to the humidifier water contaminants, and to test the ability of specific symptoms to predict this antibody response. METHODS: Symptoms from 88 factory workers were surveyed by a doctor administered questionnaire and compared with their serum IgG antibody titres to humidifier water contaminants quantified by enzyme immunoassay. RESULTS: The strength of association between individual symptoms and antibody showed that fever, shivering or chills, influenza-like symptoms, or headache were individually significantly associated with the presence and higher titres of antibody. This was also true for those subjects whose symptoms were most pronounced during the first day of the working week. Within each subject's full symptom profile there were significant associations between the description of chest tightness, breathlessness, and wheeze; between headache and influenza like symptoms; between fever and shivering or chills; and between intermittent onset and general tiredness. Discriminant analysis of the full symptom profiles showed that there was maximum information content in five independent parameters, namely, the descriptions of fever, headache, and chest tightness, the timing of their onset, and the readiness to describe miscellaneous symptoms in addition to those in the questionnaire. On the basis of these criteria 72% of subjects could be classified according to their antibody state. Cluster analysis with these five independent parameters described four symptom clusters: one associated with high median antibody levels, one with low, and two with zero median levels. These were, respectively: (1) fever with headache and chest tightness; (2) either no or few symptoms; (3) chest tightness and headache with intermittent onset; (4) headache and miscellaneous symptoms with intermittent onset. CONCLUSIONS: The association between serum antibody titres and specific symptom patterns may identify different categories of disease which constitute the spectrum known as humidifier related disease, and strengthens the hypothesis that antibody may be involved in the pathogenesis of some components of the disease.

Antibodies↗
PubMed1992

The EEG of the sleep onset period in insomnia: a discriminant analysis.

A period of rapid change in the wave components of the electroencephalogram (EEG) marks the transition from wake to sleep. Twenty-six insomniac and 28 control nights were studied in a discriminant analysis to determine whether this transitional state is modified in any way in subjects diagnosed for psychophysiological insomnia. A discriminant function was derived based on 20 insomniac and 22 normal nights. All 42 nights were correctly classified by this function. The sleep onset period, extending on the average over about 3 minutes, was characterized essentially by the beta and delta components of the EEG signal and by an activity index given by the ratio beta/delta, measured at the temporal lobe sites. Other variables included the subject's age and the magnitude of the changes occurring in the difference between activities in the right and left hemispheres. The variables contributing most to the discrimination were the activity index and beta, especially at the transitions from wake to stage 1 and from stage 1 to stage 2. The contribution of delta to the discrimination was less, but extended further in time to include stage 2 sleep. A test on the remaining six insomniac and six control nights gave a 75% classification accuracy, thus validating the derived discriminant function.

Adolescent↗
PubMed1980

Prediction of the histological type of glomerulonephritis. Multiple discriminant analysis of clinical and laboratory characteristics at time of diagnosis.

We performed a prospective study on 68 subjects with biopsy-proven clomerulonephritis using a discriminant analysis of 12 clinical and laboratory characteristics. Among these, the selectivity of proteinuria, the presence of hematuria and the plasma level of C3 proved to be the most useful. An equation based on these three variables discriminated without overlap between 17 patients with minimal change glomerulonephritis (MCGN) and 30 patients with either membranoproliferative or rapidly progressive glomerulonephritis. However, some overlap existed between MCGN and focal sclerosis or membranous glomerulonephritis. In addition, the formula seems to identify steroid-resistant patients with MCGN.

Adolescent↗
PubMedDate not supplied

Discriminant analysis indicates a single sperm protein (SP22) is predictive of fertility following exposure to epididymal toxicants.

In a previous study, we found that ethane dimethanesulphonate (EDS) compromised the fertilizing ability of proximal cauda epididymal sperm from the rat within 4 days of exposure, an effect that persisted in castrated, testosterone (T)-implanted animals, establishing direct action on the epididymis. This EDS-induced reduction in fertilizing ability was highly correlated with a quantitative decrease in specific sperm protein. Here we sought to determine whether the fertility of proximal cauda epididymal sperm recovered from animals exposed to a variety of male reproductive toxicants could be predicted by assessing quantitative changes in specific sperm protein(s), or whether more common endpoints (e.g., sperm motility, sperm morphology, serum and epididymal tissue T, cauda epididymal sperm reserves) also are required to predict fertility. Intact adult male rats were dosed with EDS (25 or 50 mg/kg), chloroethylmethanesulphonate (CEMS; 12.5 or 18.75 mg/kg), or epichlorohydrin (EPI; 3 or 6 mg/kg) daily for 4 days. Castrated, T-implanted rats were dosed with hydroxyflutamide (HFLUT; 12.5 or 25 mg/kg) daily for 5 days. On day 5, proximal cauda epididymal sperm were inseminated in utero into receptive, cervically stimulated adult females, and on day 9, fertility (implants/corpora lutea) was assessed. Fertility-was decreased by the higher dose of each toxicant (P < 0.05) and also by the lower dose of EPI and HFLUT. Likewise, an acidic 22 kDa sperm protein (SP22) was decreased quantitatively (P < 0.05) in silver-stained two-dimensional gels by the higher dose of each toxicant as well as by the lower dose of EPI and HFLUT. Although sperm motility and serum T were altered by specific exposures, these endpoints were not useful in predicting fertility. In contrast, SP22 was highly correlated (P < 0.0001; r2 = 0.83) with fertility. Indeed, the amount of SP22 correctly predicted 90% and 94% of the fertile (> 50% fertility) and subfertile (< 50 fertility) animals, respectively, when discriminant analysis was performed. Thus, the amount of SP22 in a cauda epididymal sperm sample may be a useful predictor of fertility in toxicant-treated animals.

Animals↗
PubMed1985

Factors associated with pulmonary infarction. A discriminant analysis study.

To determine the relative importance of multiple interrelated factors that have been considered to contribute to pulmonary infarction, the authors performed a discriminant analysis on consecutively autopsied patients with pulmonary embolism. From the clinic records of 45 individuals, the authors tabulated the underlying illness, history of valvular or ischemic heart disease, right and left ventricular failure, sepsis, shock, malignancy, premortem functional status, and the clinician's suspicion of pulmonary embolism. At postmortem examination, the authors measured and recorded the extent of emphysema, pneumonia, neoplasia, pulmonary vascular atherosclerosis; thickness and dilatation of both cardiac ventricles; the presence of valvular heart disease; the number, diameter, and amount of occlusion of the pulmonary arteries that contained thromboemboli; the extension of the clot, the size of the infarct; the Reid-Index; and the thickness of pulmonary and bronchial arterial wall. The major determinants of infarction were as follows: poor premortem functional status, the number of lobes having emboli, left ventricular failure, and the presence of lung cancer. The authors then tested the equation generated from these patients on 21 additional patients. The discriminant function correctly classified 81% of first group and predicted the occurrence of infarction in new patients with 70% accuracy. The size of the infarct was most correlated with the use of vasodilators and the embolic burden.

Aged↗
PubMed1987

Discriminant analysis in predicting survival of patients with cancer of the larynx or hypopharynx.

In order to assess the feasibility of computer-assisted prognostication, step-wise discriminant analysis was applied to data retrospectively obtained from 243 patients who underwent surgery for cancer of the larynx. In all, 62 variables were studied in each patient. Ninety-four out of 243 patients had complete information on the 62 variables studied. With data from these 94 patients a linear discriminant function was obtained, with an overall accuracy of 87.2%. The rate of correct prediction was 84.6% for cancer recurrence, and 88.2% for survival without recurrence. Only 11 variables of the 62 used for analysis were necessary to obtain these results. This paper confirms the usefulness of multivariate analysis in clinical practice.

Carcinoma, Squamous Cell↗
PubMed1980

Evaluation of biochemical and immunological parameters in patients with lung cancer by discrimination analysis.

Data obtained by biochemical and immunological tests in a group of healthy blood donors and a group of patients with lung cancer were subjected to discrimination analysis in order to find the minimum possible combination of methods which permit reliable differentiation of the two groups., It was revealed that the lymphocyte transformation after stimulation with PHA, the formation of E rosettes and the plasma level of glycoproteins permit complete differentiation between the group of patients and healthy controls. Based on the above three tests discrimination rules can be defined. If 52.73249--0.45913.ROS--0.40752. TRLY + 0.02790 GP greater than or equal to 0, the investigated subject can be included in the group of patients, when the values are smaller, the subject is healthy.

Alpha-Globulins↗