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Results for “Logistic Models”

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At least 883 records · Page 49Linked to original sources

PubMed1999

Epidemiological study of the risk factors of rampant caries in Shanghai children.

OBJECTIVE: To explore the risk factors associated with rampant caries and to provide suggestions for prevention and clinical treatment. METHODS: On the basis of a field survey, case-control study was performed to isolate variables possibly related to rampant caries in children. Data analysis was performed with individual analysis and multiple unconditional logistic regression. Four logistic models were developed. RESULTS: The risk factors of rampant caries were cariogenic foods and bottle-feeding with sugar containing bovine milk; an increased risk of caries was also associated with duration of breast-feeding. CONCLUSION: Overuse of cariogenic foods and unsuitable patterns of infant feeding were the most important risk factors associated with rampant caries.

Bottle Feeding↗

PubMed1994

The relationship between employer health insurance characteristics and the provision of employee assistance programs.

Workplace drug and alcohol abuse imposes substantial costs on employers. In response, employers have implemented a variety of programs to decrease substance abuse in the workplace, including drug testing, health and wellness programs, and employee assistance programs (EAPs). This paper focuses on the relationship between enterprises' organizational and health insurance characteristics and the firms' decisions to provide EAPs. Using data from the 1989 Survey of Health Insurance Plans (SHIP), sponsored by the Health Care Financing Administration (HCFA), we estimated the prevalence of EAPs by selected organizational and health insurance characteristics for those firms that offer health insurance to their workers. In addition, we estimated logistic models of the enterprises' decisions to provide EAPs as functions of the extent of state substance abuse and mental health insurance mandates, state-level demographic variables, and organizational and health insurance characteristics. Our results suggest that state mandates and demographic variables, as well as organizational and health insurance characteristics, are important explanatory variables of enterprises' decisions to provide EAPs.

Centers for Medicare and Medicaid Services, U.S.↗

PubMed1995

[A case-control study of life styles associated with myocardial infarction].

Preclinical events, especially life styles associated with myocardial infarction (MI), were evaluated in a case-control study. A total of 56 male cases were studied along with matched (1:2) controls. Cases were diagnosed at the Department of Cardiovascular Medicine, Hokkaido University School of Medicine and its related hospitals. Cases were matched to two controls each according to sex, age (+/- 3 year) and residence in central Hokkaido. Preclinical life events (diet, alcohol and smoking, working environment, health behaviors, social life etc.) were inquired in a one-to-one personal structurized interview. In order to evaluate univariate effects and the combined effects of the major multivariate variables, unconditional logistic model was used. The 14 independent variables revealing significant associations with MI were screened in the four areas of lifestyles, 1) diet: more consumption of rice-based non-fat sweets, less consumption of vegetable salads, irregular meal times, 2) alcohol and smoking: non-drinker as well as excessive drinker of alcohol, more than 30 cigarettes per day, 3) working environment, social association and personality: more than 10 hours work per day, feelings not shared with family about work, difficulty in reorientation during concentration, being easily moved to tears and 4) health-promotion, leisure and life style: not eager to watch TV programs on health, not eager to read health articles in newspaper, irregular sleep times, not watching TV in leisure time. Combined odds ratios were calculated in a multivariate logistic analysis, which disclosed phenomenal elevation of the risks in those having more lifestyle factors associated with MI.

Aged↗

PubMed2002

The relationship between oral health status and Body Mass Index among older people: a national survey of older people in Great Britain.

AIMS: To assess the relationship between oral health status and Body Mass Index. MATERIAL AND METHODS: This paper relates to the free-living sample (participants who lived in their own home, rather than an institution) of the National Diet and Nutrition Survey: people aged 65 years and older. SUBJECTS: 629 adults. DATA COLLECTION: A probability random national sample of adults who had a dental examination, an interview and an anthropometric examination. DATA ANALYSIS: Fisher's exact test and multivariate logistic modeling. FINDINGS: Being underweight was relatively uncommon in this population. People without teeth were significantly (P=0.05) more likely to be underweight than those with 11 or more teeth; 12.3% and 2.9%. A highly statistically significant (P=0.001) difference was observed in BMI between dentate people with 1-10 teeth and with more than 10 teeth; 24% and 2.9% were underweight. Dentate people with less than 21 natural teeth were on average more than 3 times more likely to be obese than those with 21-32 teeth (P=0.036). There was no significant difference in both the proportion of overweight and obese adults between those who were edentulous and dentate with 21 or more teeth. A similar pattern was observed when the number of posterior occluding pairs was compared with BMI categories. Results of multiple logistic regression were adjusted for the confounding effects of age, social class, region of origin and partial denture wearing. CONCLUSIONS: Older people in Britain with more than 20 teeth are more likely to have a normal Body Mass Index.

Aged↗

PubMed2001

Abnormal fetal heart rate tracing patterns during the first stage of labor: effect on perinatal outcome.

OBJECTIVE: The purpose of this study was to evaluate perinatal outcomes of infants who had pathologic fetal heart rate tracings during the first stage of labor, in comparison with pregnancies with normal tracings. STUDY DESIGN: The perinatal outcomes of 301 infants born at 37 to 42 weeks of gestation with pathologic fetal heart rate patterns during the first stage of labor were compared with 300 infants with normal fetal heart rate tracing patterns. The data were collected prospectively. Tracings were interpreted with the use of the National Institute of Child Health and Human Development fetal heart rate monitor guidelines. RESULTS: Hydramnios (odds ratio, 7.68; 95% CI, 1.75%-33.63%), oligohydramnios (odds ratio, 2.74; 95% CI, 1.01%-7.39%), and the presence of meconium-stained amniotic fluid (odds ratio, 1.91; 95% CI, 1.03%-3.3%) were independent factors that were associated with pathologic fetal heart rate monitoring during the first stage of labor in a multivariable analysis. The occurrences of umbilical arterial pH of <7.20, a 1-minute Apgar score of <7, a base deficit of 12 mmol/L or higher, and operative deliveries were significantly higher in the study group as compared with subjects with normal fetal heart rate monitoring. Late decelerations and severe variable decelerations (<70 bpm) during the first stage of labor were independent risk factors (odds ratio, 17.5; 95% CI, 1.61%-185.7% and odds ratio, 3.9; 95% CI, 1.36%-11.7%, respectively) that were associated with fetal acidosis (determined by both pH of <7.2 and a base deficit of 12 mmol/L or higher) in a multiple logistic model, controlled for hydramnios, oligohydramnios, meconium-stained amniotic fluid, augmentation by oxytocin, nulliparity, duration of first stage of labor, and birth weight. CONCLUSION: The operative delivery rate was higher among patients with abnormal first-stage fetal heart rate patterns. Late decelerations and severe variable decelerations were significant factors associated with fetal acidosis.

Apgar Score↗

PubMed2006

Predictors of mortality for lower respiratory infections in nursing home residents with dementia were validated transnationally.

BACKGROUND AND OBJECTIVE: Generalizability of clinical predictors for mortality from lower respiratory infection (LRI) in nursing home residents has not been assessed for residents with dementia. STUDY DESIGN AND SETTING: In prospective cohort studies of LRI in 61 nursing homes in the Netherlands (n = 541) and 36 nursing homes in Missouri, USA (n = 564), we examined 14-day and 1- and 3-month mortality in residents with dementia who were treated with antibiotics. RESULTS: A logistic model predicting 14-day mortality derived from Dutch data included eating dependency, elevated pulse, decreased alertness, respiratory difficulty, insufficient fluid intake, high respiratory rate, male gender, and pressure sores. After adjusting coefficients with the heuristic shrinkage factor, the 14-day model showed good discrimination and calibration in both datasets. The apparent c-statistic for the original Dutch model was 0.80 (after correction for optimism, it was 0.75); the c-statistic was 0.74 in the U.S. validation population. The models predicting 1- and 3-month mortality showed moderate performance. A scoring system for estimating 14-day mortality performed equally well as the original model. CONCLUSION: We identified a set of credible clinical predictors that are easily assessed and demonstrated validity in identifying residents at low risk of dying from LRI across different nursing home populations. This tool should inform decision-making for families and doctors.

Aged↗

PubMed2003

Social support networks and type of neurotic symptom among adults in British households.

BACKGROUND: Current knowledge about associations between psychosocial factors and non-psychotic symptoms provide little information about their relationship to specific types of neurotic symptoms such as symptoms of fatigue, worry, phobic anxiety and obsessional symptoms. METHOD: The British National Survey of Psychiatric Morbidity was based on a cross-sectional random sample of 10,108 householders. Neurotic symptoms were established by lay interviewers using the revised fully structured Clinical Interview Schedule (CIS-R). Subjects were asked about perceived social support, the size of their close primary social network and sociodemographic attributes. To assess possible associations between specific types of neurotic symptoms and psychosocial risk factors multivariate Huber logistic models (a modified form of repeated measures design modelling) was used taking account of correlation between symptom types and sampling design including clustering. RESULTS: After controlling for sociodemographic factors the risk of having a high total CIS-R score (> or = 12) was approximately doubled for both types of poor social functioning. Specific types of neurotic symptoms were associated both with a small primary group and with inadequate perceived social support. Depression, depressive ideas and panic symptoms had a higher prevalence in multivariate models. Poverty was associated with low support. CONCLUSIONS: Associations with deficiencies in social support and self-reported neurotic symptoms are better explained by symptom type and in particular by depression than by the total number of symptoms. If confirmed by longitudinal study findings this knowledge could be used to inform the development of interventions to improve social support in order to reduce specific neurotic symptom types.

Adolescent↗

PubMed1999

Methods for analyzing referral patterns.

OBJECTIVE: To develop a sound method to identify patient and physician characteristics that influence specialty referrals. DESIGN: A retrospective cohort analysis of medical claims data from 1996 supplemented with surveys of primary care physicians. SETTING: A 600-member independent practice association in southeastern Michigan that provided care for 90,000 members of an HMO. PATIENTS: Five cohorts, each of 2,000 to 6,000 patients with diagnoses that could be referred to cardiologists, ophthalmologists, pulmonologists, orthopedists, or general surgeons. MAIN RESULTS: The referral rates for the different cohorts ranged from 1% to 7%. The discriminatory ability of the multivariate logistic models (c-statistic) ranged from 0.66 to 0.79. The likelihood of referral was associated with the patient's diagnoses and medications and with the referring physician's age, years out of medical school, satisfaction with the specialty being referred to, and the importance of making or confirming a diagnosis. CONCLUSIONS: Because these methods were not difficult to implement and the results were credible, we believe that other organizations should be able to use them.

Cohort Studies↗

PubMed1998

Factors associated with restraint use of children in fatal crashes.

OBJECTIVE: This study was designed to characterize the restraint use of children in fatal crashes and to determine factors that were related to child restraint use. METHODS: Crashes in which a vehicle occupant died were selected from the 1994 Fatal Analysis Reporting System data. Restraint use of children (0-9 years) in these crashes was characterized and examined in relation to vehicle and driver characteristics. RESULTS: Restraint use declined with increasing age of children and increasing number of occupants. Restraint use was also lower in older vehicles, in pickups and large vans, between 3 AM and 6 AM, and in rural areas. Driver characteristics associated with lower restraint use of child passengers included unrestrained drivers, younger drivers, and alcohol use at the time of crash. Driver restraint use was the strongest predictor of child restraint use. Differences in restraint use by age of the child, number of occupants, time, urban/rural area, and driver restraint use persisted in a logistic model. CONCLUSION: Restraint use in crashes is substantially lower than that in observational studies, suggesting that these studies are not reflective of high-risk conditions for crashes in which children are involved. Child occupant protection counseling must stress restraint use under all conditions of travel. Local, state, and national efforts must be aimed at increasing family occupant protection for the entire family.

Accidents, Traffic↗

PubMed2000

Gene-covariate interaction between dysplastic nevi and the CDKN2A gene in American melanoma-prone families.

The CDKN2A gene has been implicated in cutaneous malignant melanoma pathogenesis. Although CDKN2A mutations confer substantial risk for melanoma, clinicoepidemiological covariates including dysplastic nevi (DN), total nevi, and solar injury also enhance melanoma risk. To examine the relationship between CDKN2A and these three risk factors, we conducted combined segregation/linkage analysis using the class D regressive logistic model, as implemented in the computer program REGRESS. Genetic and covariate data were collected on 20 American melanoma-prone families, 13 of which had cosegregating CDKN2A mutations. Two types of analyses were conducted. The missing-indicator method used a missing-value indicator, set to 1 for unknown and 0 for known covariate status, and a second variable set to 1 for exposed and 0 for unexposed or unknown. The second method, complete-cases method, coded subjects with missing covariates as unknown for the affection status. The results for both analyses were very similar. Overall, there was a significant improvement in the likelihood when DN, total nevi or both covariates were added to the base model, which included dominant transmission of the CDKN2A gene and a linear increase of risk with the logarithm of age on the logit scale. In contrast, inclusion of solar injury did not significantly improve the likelihood for the base model. Significant evidence for a gene-covariate interaction was detected between DN and CDKN2A when DN was the only covariate in the model (missing-indicator method or complete-cases method) or when both DN and total nevi were in the model (complete-cases method only). Interestingly, in both methods, the odds ratio (OR) for DN was greater in subjects without mutations (OR, 20.1; 95% confidence interval, 4.8-92.8) versus those with CDKN2A mutations (OR, 3.3; 95% confidence interval, 1.1-10.0; complete-cases method). The CDKN2A-DN interaction illustrates the complex etiology of melanoma and needs to be confirmed in a larger sample of families.

Adolescent↗

PubMed2001

Expectant treatment of ectopic pregnancies: clinical and sonographic predictors.

OBJECTIVE: We identified the potential clinical and sonographic predictors of the spontaneous resolution of ectopic pregnancies. SUBJECTS AND METHODS: We performed a prospective study of 78 consecutive patients with a transvaginal sonographic diagnosis of ectopic pregnancy who had either two consecutive quantitative measurements of their beta subunit of human chorionic gonadotropin (beta-hCG) more than 24 hrs apart or an embryo with a heart beat. We evaluated the patient's age, time from the last menstrual period, beta-hCG level, size of ectopic pregnancy, presence of a gestational sac or embryonic elements, vascularity on color Doppler sonography, peak systolic velocity, and resistive index of ectopic pregnancy at the time of presentation as potential independent predictors of the final outcome. Logistic regression was performed to identify the independent predictors. RESULTS: Forty-six patients had declining beta-hCG levels, and 32 ectopic pregnancies showed an embryo with a heart beat or had steady or rising beta-hCG levels. Univariate analysis indicated that a longer time from the last menstrual period (older ectopic pregnancies), lower beta-hCG levels, and the absence of gestational sac are statistically more significantly seen in ectopic pregnancies with declining beta-hCG levels (p < 0.05). Resistive index of ectopic pregnancy reached borderline significance (p = 0.05). In a multiple logistic model, the same variables were independent predictors of outcome (p < 0.05). Resistive index was also a predictor (p = 0.09). CONCLUSION: Longer times from the last menstrual period, lower beta-hCG levels, absence of gestational sacs, and higher resistive indexes of ectopic pregnancy at the time of presentation appear to be independent predictors of the spontaneous resolution of ectopic pregnancy.

Adult↗

PubMed2003

Designing a Brief Alzheimer Screen (BAS).

CONTEXT: With advances in the treatment of Alzheimer's disease (AD), clinical focus has shifted to early patient identification. Memory recall tests and category fluency distinguish normal individuals from early AD patients. OBJECTIVE: Develop a brief test for general practitioners to screen for AD. Design. Examination of items from the MMSE and category fluency. SETTING AND PARTICIPANTS: A Brief Alzheimer Screen (BAS) was developed from cognitive assessments on 406 normal subjects and 342 mild AD patients in the CERAD (Consortium to Establish a Registry for AD) dataset. The derived measure was then applied to a second validation sample. MAIN OUTCOME MEASURE: Logistic regression was used to derive a predictive equation, which was then applied to two validation samples to estimate sensitivity and specificity. RESULTS: The resulting logistic model for discriminating between mild AD and controls included: recall of 3 words, number of animals named in 30 seconds, date, and spelling of WORLD backwards, (p < 0.001 for each) accounting for 77% of the variance. When applied to the validation samples, sensitivity and specificity were over 99% and 87%, respectively. CONCLUSIONS: These data support the use of the BAS as a potential screen of patients over 60 years of age.

Aged↗

PubMedDate not supplied

Factors influencing mortality of acute intestinal infarction associated with SIRS.

BACKGROUND/AIMS: In patients with acute mesenteric ischemia, early diagnosis is considered to improve the prognosis by preventing the occurrence of systemic inflammatory response syndrome (SIRS). However, it remains unclear which factors affect the mortality once advanced ischemia and SIRS develop in cases of delayed diagnosis. The aim of this study was to investigate the predictors of in-hospital mortality in the late stage of acute mesenteric ischemia. METHODOLOGY: We retrospectively studied 66 consecutive patients who had acute intestinal infarction associated with SIRS between 1986 and 2002. They included 19 of acute mesenteric thromboembolism and 47 cases of postoperative adhesions or an incarcerated hernia. A multivariate logistic model was used to identify important factors for in-hospital death among the background data. Two models were constructed with/without the cause of intestinal obstruction as a variable, since it might affect the prognosis. RESULTS: The results suggested that concomitant cardiac morbidity, high serum amylase level, and thrombocythemia are important factors for in-hospital mortality of acute intestinal infarction, regardless of the cause of intestinal infarction. CONCLUSIONS: Our results indicated that the prognosis is strongly influenced by associated cardiac morbidity and abnormal coagulopathy in the advanced stage of mesenteric ischemia.

Acute Disease↗

PubMedDate not supplied

A measure of mortality risk for elderly patients with acute myocardial infarction.

The objective of this study was to derive and validate a simple scoring system that predicts risk of short-term mortality in elderly patients hospitalized with acute myocardial infarction (AMI) and to compare this derived score with the MedisGroups admission severity score. A myocardial infarction severity score (MISS) was derived from a database of clinical information abstracted using MedisGroups and follow-up information on 30-day mortality status. The MISS was validated and compared with the MedisGroups Admission Severity Groups (ASGs) in a separate database. The derivation set included 2,037 Medicare patients 65 years old or older with confirmed AMI who were randomly selected from patients discharged from hospitals in seven states during 1985. The validation set consisted of 6,323 patients from the 1988 MedisGroups comparative database who were at least 65 years of age and had confirmed AMI. Multivariate logistic regression analysis found a set of nine abnormal patient characteristics that independently predict 30-day mortality. There was good agreement between mortality rates predicted by the logistic model and observed mortality rates in the validation population. This regression model was then simplified to an additive score where eight of the characteristics were weighted as one point and one characteristic was weighted as two points. The MISS is the sum of the points for each patient. In the validation dataset, the 1,373 patients with the lowest MISS scores had a mortality rate of 4.6% and the 400 patients with the highest MISS scores had a mortality rate of 64%.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1996

An adolescent tobacco-use prevention trial in orthodontic offices.

OBJECTIVES: This study examined the effect of an orthodontist-delivered tobacco-use prevention program for adolescents. METHODS: Southern California orthodontic offices were randomly assigned to experimental (n = 77) and control (n = 77) groups. Randomly selected adolescents were interviewed at baseline and 2 years later (n = 15,644). Experimental offices received tobacco prevention training, anti-tobacco materials, and 50 cents for each anti-tobacco "prescription" written. RESULTS: The 30-day tobacco use 2-year incidence rates for the control and experimental groups were 12.6% and 12.0%, respectively; incidence rates for using tobacco more than 100 times were 7.6% and 6.8%. Differences between the groups did not reach significance. Mean prescription compliance was 64.4%. A multivariate logistic model, showed a significant dose response: patients who received more prescriptions had lower incidence rates than those who received few or none (10% vs 14%). CONCLUSIONS: Training, payment, and support did not ensure clinician compliance with prevention services. The dose effect suggests that replication under conditions that would ensure clinician compliance and statistical power would more thoroughly test clinicians' ability to prevent tobacco use.

Adolescent↗

PubMed1983

Characteristics of first pregnancy in relation to early breast cancer. A case-control study.

We examined some characteristics of first pregnancy in 314 female breast cancer patients whose disease was diagnosed at < 45 years of age and who were identified through a population-based cancer registry in New York State and in 314 control women identified through birth records. Preeclampsia was reported less frequently on the birth records of the first recorded pregnancy in the cases than in those of the controls, with a relative risk of 0.28 (0.05 < p < 0.10, from logistic model). We examined this finding on preeclampsia with particular reference to immunologic mechanisms, but further studies are needed on larger samples. Twinning and maternal Rh factor, also relevant to immunologic factors, were not significantly associated with a higher risk of breast cancer. Among the women whose first pregnancy resulted in a live birth, length of gestation (which is correlated with maternal estriol levels) did not differ between the cases and controls.

Adult↗

PubMed2002

Evaluation of the Society for Coronary Angiography and Interventions' lesion classification system in 14,133 patients with percutaneous coronary interventions in the current stent era.

We recently showed that the ACC/AHA coronary lesion classification could be simplified with no loss of predictive value (SCAI I = patent/non-C; SCAI II = patent/C; SCAI III = occluded/non-C; SCAI IV = occluded/C). We now test this system in a database reflecting current stent usage. Data from 14,133 patients with single-native-vessel interventions recorded in the Society for Coronary Angiography and Interventions (SCAI) Registry from July 1996 to July 1999 were analyzed. Stents were used in 60.2% of procedures. Logistic models predicting angiographic success suggested a slight, clinically insignificant preference for the SCAI classification (c-statistic = 0.692 vs. 0.670). Models using clinical variables to predict major complications were superior to models using only lesion classification. Lesion characteristics were related to outcomes primarily in elective (not acute myocardial infarction) patients. In the current PCI device era, the simpler SCAI classification using 7 variables predicted interventional success and complications as well as or better than the ACC/AHA system requiring 26.

Aged↗

PubMed1994

Pancreatic resection for periampullary carcinoma in the elderly.

The effect of pancreatic resection for periampullary carcinoma in the elderly was studied by comparing the pre- and perioperative factors affecting survival in 102 patients less than 70 years of age (group A) with those in 28 patients 70 years and older (group B). Concomitant cardiac and pulmonary diseases were significantly more frequent in group B (P < 0.05), but the difference in routine laboratory data was not significant. The overall operative mortality was 7% (7/102) in group A and 18% (5/28) in group B, while the actuarial 5-year survival rates were 31% in group A and 23% in group B, these differences not being significant. A multivariate analysis using a logistic model showed that blood loss was the greatest risk factor for early postoperative death in the elderly patients, whereas anastomotic dehiscence and postoperative bleeding were significant factors in the younger patients. Thus, we conclude that age is not a contraindication to pancreaticoduodenectomy which offers the only hope for long-term survival in patients with periampullary carcinoma; however, meticulous dissection to minimize blood loss is especially important in elderly patients.

Actuarial Analysis↗