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PubMed1998

Inter- and intraquinolone predictors of antimicrobial effect in an in vitro dynamic model: new insight into a widely used concept.

Earlier efforts to search for pharmacokinetic and bacteriological predictors of fluoroquinolone antimicrobial effects (AMEs) have resulted in conflicting findings. To elucidate whether these conflicts are real or apparent, several predictors of the AMEs of two pharmacokinetically different antibiotics, trovafloxacin (TRO) and ciprofloxacin (CIP), as well as different dosing regimens of CIP were examined. The AMEs of TRO given once daily (q.d.) and CIP given q.d. and twice daily (b.i.d.) against Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae were studied in an in vitro dynamic model. Different monoexponential pharmacokinetic profiles were simulated with a TRO half-life of 9.2 h and a CIP half-life of 4.0 h to provide similar eightfold ranges of the area under the concentration-time curve (AUC)-to-MIC ratios, from 54 to 432 and from 59 to 473 (microg x h/ml)/(microg/ml), respectively. In each case the observation periods were designed to incorporate full-term regrowth phases in the time-kill curves, and the AME was expressed by its intensity (IE; the area between the control growth and time-kill and regrowth curves up to the point at which the viable counts of regrowing bacteria are close to the maximum values observed without drug). Species-independent linear relationships were established between IE and log AUC/MIC, log AUC above MIC (log AUCeff), and time above the MIC (Teff). Specific and nonsuperimposed IE versus log AUC/MIC or log AUCeff relationships were inherent in each of the treatments: TRO given q.d. (r2 = 0.97 and 0.96), CIP given q.d. (r2 = 0.98 and 0.96), and CIP given b.i.d. (r2 = 0.95 and 0.93). This suggests that in order to combine data sets obtained with individual quinolones to examine potential predictors, one must be sure that these sets may be combined. Unlike AUC/MIC and AUCeff, the IE-Teff relationships plotted for the different quinolones and dosing regimens were nonspecific and virtually superimposed (r2 = 0.95). Hence, AUC/MIC, AUCeff and Teff were equally good predictors of the AME of each of the quinolones and each dosing regimen taken separately, whereas Teff was also a good predictor of the AMEs of the quinolones and their regimens taken together. However, neither the quinolones nor the dosing regimens could be distinguished solely on the basis of Teff whereas they could be distinguished on the basis of AUC/MIC or AUCeff. Thus, two types of predictors of the quinolone AME may be identified: intraquinolone and/or intraregimen predictors (AUC/MIC, AUCeff and Teff) and an interquinolone and interregimen predictor (Teff). Teff may be able to accurately predict the AME of one quinolone on the basis of the data obtained for another quinolone.

Anti-Infective Agents↗

PubMed2006

Electrocardiographic predictors of incident congestive heart failure and all-cause mortality in postmenopausal women: the Women's Health Initiative.

BACKGROUND: Information is limited about ECG predictors of the risk of incident congestive heart failure (CHF), particularly in women without overt manifestations of cardiovascular disease (CVD). METHODS AND RESULTS: We evaluated hazard ratios for incident CHF and all-cause mortality using Cox regression in 38,283 participants of the Women's Health Initiative (WHI) during a 9-year follow-up. All risk models were adjusted for demographic and available clinical and therapeutic variables (multivariable-adjusted models). A backward selection procedure was used to identify dominant predictors among those that were significant as individual ECG predictors. Eleven ECG variables were significant predictors of incident CHF, with none of them having a significant interaction with baseline CVD status. From 6 dominant ECG predictors, wide QRS/T angle had a nearly 3-fold increased risk in multivariable-adjusted single ECG variable models. Two other repolarization variables, STV5 depression and high TV1 amplitude, and 2 QRS-related variables, QRS non-dipolar voltage and myocardial infarction (MI) by ECG, were all associated with &2-fold increase of incident CHF risk. Overall, 11 of the 12 ECG variables were significant predictors of all-cause mortality. Four variables had a significant interaction with CVD status requiring stratification. Three among these 4 were strong, dominant predictors in the CVD group: ECG MI, wide QRS/T angle, and low TV5 amplitude had risk increase from >2-fold to 3-fold, with considerably lower risks in the CVD-free group. CONCLUSIONS: Several repolarization variables in postmenopausal women are predictors of the risk of incident CHF and all-cause mortality as important as old ECG MI.

Age Distribution↗

PubMed1993

Predictors of asthma and wheezing in adults. Grain farming, sex, and smoking.

We investigated predictors for asthma and wheeze in 1,634 men and women in the age group 20 to 65 yr from the town of Humboldt, Saskatchewan. On the basis of questionnaire responses, subjects were classified into mutually exclusive groups as asthmatic (n = 62), wheezing (n = 444), asymptomatic (n = 908), and symptomatic (n = 220) groups. After excluding the symptomatic group, we used polytomous logistic regression models to determine predictors of asthma and wheezing. Significant predictors for asthma were grain farming (odds ratio [OR] = 1.9, 95% confidence interval [Cl]: 1.1-3.5; p = 0.03) and sex (OR = 1.9, Cl: 1.1-3.2; p = 0.03; males compared with females). Significant predictors for wheezing were smoking (former smoker: OR = 1.8, Cl: 1.3-2.5, p < 0.001; current smoker: OR = 5.0, Cl: 3.8-6.7, p < 0.001; in comparison to nonsmoker) and grain farming (OR = 1.7, Cl: 1.3-2.4, p < 0.001). Age, level of education, and physical activity at work were not significant predictors for asthma or wheezing. None of the interaction effects between the predictors was significant. When stratified by sex, grain farming was a significant predictor of asthma in men but not in women. Nevertheless, smoking and grain farming were significant predictors of wheezing in both men and women. Our study raises the possibility that grain farming might be a risk factor for asthma and asthma-like symptoms.

Adult↗

PubMed2005

Predictors of antidepressant use among older adults: have they changed over time?

OBJECTIVE: Antidepressant use increased substantially among older adults with the introduction of the new-generation medications such as the selective serotonin reuptake inhibitors. The authors analyzed data from two follow-up intervals-1986-1987 to 1989-1990 (interval 1) and 1992-1993 to 1996-1997 (interval 2)-from a community-based cohort of 4,162 older adults to determine predictors of future antidepressant use. METHOD: Information on antidepressant use, demographic and health characteristics, and categories of depressive symptoms-positive affect, negative affect, somatic complaints, and interpersonal problems-were obtained. Logistic regression was used to control simultaneously for multiple variables predicting antidepressant use during the two intervals. Repeated-measures logistic regression (with generalized estimating equations) was employed to model the probability of antidepressant use, with adjustment for the effect of time. RESULTS: Prior antidepressant use and white race were strong predictors of future use during both intervals. Negative affect was the only additional significant predictor of use during interval 1. In contrast, low positive affect scores, cognitive impairment, and poorer health were additional significant predictors during interval 2. In a repeated-measures model, race, prior antidepressant use, poor health, low positive affect scores, and somatic complaints varied as predictors over time. Negative affect and cognitive impairment were consistent predictors over time. CONCLUSIONS: The predictors of antidepressant use by older adults changed over time, with health-related measures of quality of life, such as positive affect, health status, and somatic complaints, becoming more prominent as predictors of use.

Affect↗

PubMed2006

A multi-class predictor based on a probabilistic model: application to gene expression profiling-based diagnosis of thyroid tumors.

BACKGROUND: Although microscopic diagnosis has been playing the decisive role in cancer diagnostics, there have been cases in which it does not satisfy the clinical need. Differential diagnosis of malignant and benign thyroid tissues is one such case, and supplementary diagnosis such as that by gene expression profile is expected. RESULTS: With four thyroid tissue types, i.e., papillary carcinoma, follicular carcinoma, follicular adenoma, and normal thyroid, we performed gene expression profiling with adaptor-tagged competitive PCR, a high-throughput RT-PCR technique. For differential diagnosis, we applied a novel multi-class predictor, introducing probabilistic outputs. Multi-class predictors were constructed using various combinations of binary classifiers. The learning set included 119 samples, and the predictors were evaluated by strict leave-one-out cross validation. Trials included classical combinations, i.e., one-to-one, one-to-the-rest, but the predictor using more combination exhibited the better prediction accuracy. This characteristic was consistent with other gene expression data sets. The performance of the selected predictor was then tested with an independent set consisting of 49 samples. The resulting test prediction accuracy was 85.7%. CONCLUSION: Molecular diagnosis of thyroid tissues is feasible by gene expression profiling, and the current level is promising towards the automatic diagnostic tool to complement the present medical procedures. A multi-class predictor with an exhaustive combination of binary classifiers could achieve a higher prediction accuracy than those with classical combinations and other predictors such as multi-class SVM. The probabilistic outputs of the predictor offer more detailed information for each sample, which enables visualization of each sample in low-dimensional classification spaces. These new concepts should help to improve the multi-class classification including that of cancer tissues.

Algorithms↗

PubMed2002

Predictors of outcome of long-term GnRH therapy in men with idiopathic hypogonadotropic hypogonadism.

GnRH treatment is successful in inducing virilization and spermatogenesis in men with idiopathic hypogonadotropic hypogonadism (IHH). However, a small subset of IHH men, poorly characterized to date, fail to reach a normal testicular volume (TV) and produce sperm on this therapy. To determine predictors of outcome in terms of TV and sperm count, we studied 76 IHH men (38% with anosmia) undergoing GnRH therapy for 12-24 months. The population was stratified according to the baseline degree of prior pubertal development: absent (group 1, n = 52), partial (group 2, n = 18), or complete (adult onset HH; group 3, n = 6). Cryptorchidism was recorded in 40% of group 1, 5% of group 2, and none in group 3. Pulsatile GnRH therapy was initiated at 5-25 ng/kg per pulse sc and titrated to attain normal adult male testosterone (T) levels. LH, FSH, T, and inhibin B (I(B)) levels were measured serially, and maximum sperm count was recorded. A longitudinal mixed effects model was used to determine predictors of final TV. LH (97%) and T (93%) levels were normalized in the majority of IHH men. Groups 2 and 3 achieved a normal adult testicular size (92%), FSH (96%), I(B) levels (93%), and sperm in their ejaculate (100%). However, given their prior complete puberty and thus primed gonadotropes and testes, group 3 responded faster, normalizing androgen production by 2 months and completing spermatogenesis by 6 months. In contrast, group 1 failed to normalize TV (11 +/- 0.4 ml) and I(B) levels (92 +/- 6 pg/ml) by 24 months, despite normalization of their FSH levels (11 +/- 2 IU/liter). Similarly, sperm counts of group 1 plateaued well below the normal range (median of 3 x 10(6)/ml) with 18% remaining azoospermic. The independent predictors of outcome of long-term GnRH therapy were: 1) the presence of some prior pubertal development (positive predictor; group effect (beta) = 4.3; P = 0.003); 2) a baseline I(B) less than 60 pg/ml (negative predictor; beta = -3.7; P = 0.009); and 3) prior cryptorchidism (negative predictor; beta = -1.8; P = 0.05). Notably, anosmia was not an independent predictor of outcome when adjusted for other baseline variables. Our conclusions are: 1) pulsatile GnRH therapy in IHH men is very successful in inducing androgen production and spermatogenesis; 2) normalization of the LH-Leydig cell-T axis is achieved more uniformly than the FSH-Sertoli cell-I(B) axis during GnRH therapy; and 3) favorable predictors for achieving an adult testicular size and consequently optimizing spermatogenesis are prior history of sexual maturation, a baseline I(B) greater than 60 pg/ml, and absence of cryptorchidism.

Adolescent↗

PubMed1998

Predictors for falls and fractures in the Longitudinal Aging Study Amsterdam.

The objective of this study was to identify easily measurable predictors for falls, recurrent falls, and fractures using a population-based prospective cohort study of 1469 elderly, born before 1931, in three regions of the Netherlands. The baseline at-home interview was in 1992. In 1995, falls experienced in the preceding year and fractures over the preceding 38-month period were registered. In a period of 1 year, 32% of the participants fell at least once, and 15% fell two or more times. The rate of recurrent falls was similar in men and women up until the age of 75 years. The total number of fractures was 85, including 23 wrist fractures, 12 hip fractures, and 9 humerus fractures. The incidence density per 1000 person-years for any fracture was 25.1 (95% confidence interval [CI], 18.9-31.4) for women and 8.2 (95% CI, 4.5-12.0) for men, respectively. Multiple logistic regression identified urinary incontinence, impaired mobility, use of analgetics, and use of antiepileptic drugs as the predictors most strongly associated with recurrent falls. Female gender, living alone, past fractures, inactivity, body height, and use of analgetics proved to be the predictors most strongly associated with fractures. The probabilities of recurrent falls were 4.7% (95% CI, 2.9-7.5%) to 59. 2% (95% CI, 24.1-86.9%) with zero to four predictors, respectively. The probability of fractures ranged from 0.0% (95% CI, 0.0-0.4%) without any of the identified predictors to 12.9% (95% CI, 4.4-32. 2%) with all six predictors present. Our study shows that the risk of recurrent falls and of fractures can be predicted using up to, respectively, four and six easily measurable predictors. This study emphasizes the importance of impaired mobility and inactivity as predictors for falls and fractures.

Accidental Falls↗

PubMed2005

Stent-assisted angioplasty of intracranial vertebrobasilar atherosclerosis: midterm analysis of clinical and radiologic predictors of neurological morbidity and mortality.

BACKGROUND AND PURPOSE: Initial reports of stent-assisted angioplasty for intracranial vertebrobasilar atherosclerosis suggest this is a feasible treatment, but there have been little data regarding predictors of success or failure. We analyzed a series of patients for independent predictors of neurologic morbidity and mortality. METHODS: Patient charts and angiograms from 39 patients who underwent intracranial angioplasty and stent placement of vertebrobasilar stenoses were retrospectively reviewed to obtain clinical and detailed angiographic data on potential predictors of neurologic morbidity and mortality. Univariate analyses of these predictors were performed with either Fisher's exact test or simple logistic regression. Multivariate analysis was subsequently performed on the statistically significant predictors. RESULTS: Complete clinical data were obtained for 39 patients, and angiographic review was possible for 35 of them. Angiography revealed severe intracranial vertebral (n = 18), basilar (n = 15), or basilar and vertebral (n = 2) stenoses. Two patients (5.1%) died in the periprocedural period, nine patients (23.1%) had neurologic complications, and one patient (2.6%) had transient neurologic symptoms. Univariate analysis revealed female sex, diabetes, and failure of coumadin or heparin therapy were associated with neurologic morbidity, whereas female sex, Mori B lesion, and length-to-stenosis ratio were associated with mortality. The presence of diabetes was the only independent predictor of neurologic morbidity and mortality. CONCLUSION: Because of the limited number of patients available for analysis, the only independent predictor of neurologic morbidity and mortality was diabetes, but several other predictors showed trends that deserve further review in future series.

Angioplasty↗

PubMed1991

Predictors of functional outcome and resource utilization in inpatient rehabilitation.

Consecutive patients (n = 1,289) discharged from two inpatient rehabilitation facilities were prospectively examined to determine the extent to which rehabilitative outcomes, functionally based progress, and associated resource utilization (in terms of rehabilitation length of stay) can be concomitantly predicted using the Tufts/New England Medical Center functional assessment tool and bivariate and multivariate statistical comparisons. A high percentage (greater than 50%) of statistically significant associations between the predictor variables and seven outcome measures were seen. The R2s corresponding to these associations were generally small and resistant to enhancement by commonly accepted statistical manipulations. Consequently, they are, in general, of limited predictive value for determining functional prognosis or resource utilization among rehabilitation inpatients. Although functionally based predictors appear to be the best predictors of functional progress, their effectiveness as predictors of other domains (eg, discharge outcome and rehabilitation length of stay) is variable. The implication is that a prospective payment system using such an array of predictors and directed primarily at cost containment is likely to overlook potentially important gains in functional progress and patient outcome. Furthermore, the functionally based predictors, taken individually, varied in effectiveness as predictors among facilities, and, taken collectively, they varied in effectiveness as predictors for different diagnostic groupings within a facility. The inconsistency of predictions according to the various domains appears to further limit their application to a prospective payment model.

Activities of Daily Living↗

PubMed2006

Maximum likelihood estimation of marginal pairwise associations with multiple source predictors.

Researchers interested in the association of a predictor with an outcome will often collect information about that predictor from more than one source. Standard multiple regression methods allow estimation of the effect of each predictor on the outcome while controlling for the remaining predictors. The resulting regression coefficient for each predictor has an interpretation that is conditional on all other predictors. In settings in which interest is in comparison of the marginal pairwise relationships between each predictor and the outcome separately (e.g., studies in psychiatry with multiple informants or comparison of the predictive values of diagnostic tests), standard regression methods are not appropriate. Instead, the generalized estimating equations (GEE) approach can be used to simultaneously estimate, and make comparisons among, the separate pairwise marginal associations. In this paper, we consider maximum likelihood (ML) estimation of these marginal relationships when the outcome is binary. ML enjoys benefits over GEE methods in that it is asymptotically efficient, can accommodate missing data that are ignorable, and allows likelihood-based inferences about the pairwise marginal relationships. We also explore the asymptotic relative efficiency of ML and GEE methods in this setting.

Depression↗

PubMed2004

Identifying predictors of treatment response.

This article provides a rationale for considering predictors of growth in a treatment group as inadequate to identifying predictors of treatment response. When we interpret predictors of growth in a treatment group as synonymous with predictors of treatment response, we implicitly attribute all of the treated children's growth to the treatment, an untenable assumption under most conditions. We also contend that the use of standard scores in predictors of growth studies does not allow us to differentiate growth from treatment, from growth from other factors. We present two research methodologies that are appropriate methods of identifying predictors of treatment response: (a) single-subject experimental logic utilized to identify the specific participants in which treatment responses (not just growth) were found, combined with follow-up group comparison logic to identify the characteristics on which responders and nonresponders differ, and (b) statistical interactions among child/family/context characteristics and randomly assigned group membership. Principles for selecting potential predictors of treatment response are provided.

Child↗

PubMedDate not supplied

Psychosocial predictors of different stages of cigarette smoking among high school students.

BACKGROUND: Current research on the etiology of cigarette smoking has largely focused on the identification of psychosocial predictors of tobacco onset. Few data are available on the predictors of different stages of smoking among adolescents. The present study examines the psychosocial predictors of different stages of smoking, including trial, experimental, and regular use, among high school students. METHOD: The predictor variables were measured when the students were in the 7th grade. Logistic regression was used to predict different smoking stages at grade 12. RESULTS: The results show that four domains of psychosocial variables, including social and interpersonal factors, attitudinal and belief factors, intrapersonal factors, and use of other substances, predicted one or more stages of smoking. The important correlates of transition from trial to experimental use (all P value <0.001) included friends' smoking and approval, cigarette offers by friends, smoking intentions, school grade, and alcohol and marijuana use. The significant predictors of the transition from experimental to regular use included only parental smoking (P < 0.01) and family conflicts (P < 0.05). We found some gender differences in these predictors. CONCLUSIONS: Psychosocial predictors may differ by different stages of smoking.

Adolescent↗

PubMed1998

Predictors of hospital mortality and mechanical ventilation in patients with cervical spinal cord injury.

PURPOSE: The objective of this study was to identify predictors of death and mechanical ventilation in patients with traumatic cervical spinal cord injury. METHODS: From 1981 to 1994, 72 patients with traumatic cervical spinal cord injury resulting in neurological deficits were identified in this retrospective study. For each patient, neurological and associated injuries, physiological variables, complications, hospital mortality and the need for mechanical ventilation were recorded. Univariate and multivariate logistic regression analyses were done to identify predictors of mortality and the need for mechanical ventilation. RESULTS: Fifteen patients (21%) died in the first three months after injury. Univariate analyses identified age, heart disease, neurological level at C4 and above, GCS < or = 13, forced vital capacity and cough, to be associated with mortality. Multivariate logistic regression identified age (P = 0.01), neurological level (P = 0.03) and GCS (P = 0.05) as independent predictors of mortality. In 41 patients (57%), the lungs were mechanically ventilated. Univariate analyses identified. The following predictors of the need for mechanical ventilation: neurological level at C5 and above, complete cord lesions, copious sputum, pneumonia and lung collapse. Multivariate logistic regression identified copious sputum (P = 0.01) and pneumonia (P = 0.01) as independent predictors of the need for mechanical ventilation. CONCLUSION: Age, neurological level and GCS are independent predictors of mortality in patients with traumatic cervical spinal cord injury. Copious sputum and pneumonia are independent predictors of the need for mechanical ventilation.

Adolescent↗

PubMed2000

ACC/AHA guidelines as predictors of postoperative cardiac outcomes.

PURPOSE: Recently, the American College of Cardiology - American Heart Association (ACC-AHA) published guidelines and an associated algorithm for preoperative cardiovascular evaluation of patients undergoing non-cardiac surgery. Our purpose was to (i) test guideline's ability to predict adverse cardiac events within seven days after surgery, (ii) determine whether medical clinical predictors or surgical risks was a better predictor of cardiac events. METHODS: Retrospective review of 119 cardiology and anesthesia consultations over 15 mo, ending March 31, 1998. Patients were classified into their respective medical clinical predictor and surgical risk groups, as outlined in ACC-AHA guidelines. Associations between the medical predictor and surgical risk scores and adverse cardiac outcomes were quantified via multiple logistic regression analysis. Two outcomes were employed. Outcome I, included: myocardial infarction/ischemia; angina; congestive heart failure, arrhythmia or death. Outcome 2 expanded the definition to include "cancellation of surgery due to cardiac risk" as a negative cardiac outcome. RESULTS: Diabetes, Canadian Cardiovascular Class (CCS) III or IV angina, and MI within six months before surgery were strongly associated with the two cardiac outcomes. For outcome 1 and 2, medical predictors and surgical risks, considered simultaneously, performed with a sensitivity of 93% and specificity of 46-51%. When considered separately, major clinical medical predictors had a sensitivity of 87-89%, while surgical risks showed a specificity of 89% in predicting the two outcomes. CONCLUSION: Medical predictors in ACC-AHA classification scheme were highly sensitive whereas surgical risks were more specific in predicting adverse post-operative cardiac events. Prospective study is needed to confirm these observations.

Adult↗

PubMed2000

Predictors of fractures in elderly women.

In a prospective study of 348 apparently healthy women, aged 70 years and over (mean 80.3 years), we examined bone mineral density (BMD), biochemical markers of bone metabolism, and some easily measurable predictors in relation to hip and osteoporotic fractures. In addition, we constructed risk profiles for hip and osteoporotic fractures. At baseline, BMD at both hips, using dual-energy X-ray absorptiometry, body height and body weight were measured. At the same time, serum and urine samples were obtained for biochemical analysis. Serum samples were analyzed for vitamin D metabolites, sex hormone binding globulin, serum intact parathyroid hormone, osteocalcin, alkaline phosphatase, phosphate, albumin, calcium and creatinine. In 2 h fasting urine, hydroxyproline, type I collagen crosslinked N-telopeptide (NTx) and calcium excretion were measured. Furthermore, easily measurable predictors, such as previous fracture, body mass index (BMI) and mobility were assessed. During the follow-up period (mean duration 5.0 years), hip and any osteoporotic fracture (wrist, humerus or hip fracture) occurred in 16 and 33 participants, respectively. Data were analyzed using Cox regression analysis. BMD of the trochanter (per 1 SD decrease) and previous fracture were most strongly associated with hip fractures (adjusted relative risk (RR) = 3.0, 95% confidence interval (CI): 1.4-6.6; RR = 4.2, 95% CI: 1.5-11.6, respectively) and osteoporotic fractures (RR = 1.8, 95% CI: 1.1-2.8; RR = 2.9, 95% CI: 1.5-5.7, respectively). Previous fracture, BMI and mobility were identified as easily measurable predictors for hip fractures, whereas previous fracture, use of loop diuretics and age were predictors for osteoporotic fractures in the risk profile model. The risk of fractures can be predicted with three easily measurable predictors. This study confirms the importance of previous fracture as a predictor for hip fractures and other fractures. It also shows that the use of loop diuretics is a predictor for osteoporotic fractures.

Activities of Daily Living↗

PubMed1996

Statistical comparison of established T-cell epitope predictors against a large database of human and murine antigens.

Identification of T-cell epitopes within a protein antigen is an important tool in vaccine design. The T-cell epitope prediction schemes often are exploited by workers but have proved unreliable in comparison with experimental techniques. We compared published T-cell epitope predictors against two databases of human and murine T-cell epitopes. Each predictor was assessed against random cyclic permutations of epitopes in order to determine significance. Predictor performance was expressed in terms of two parameters, specificity and sensitivity. Specificity is an expression of the quality of predictions, whereas sensitivity is an expression of the quantity of epitopes predicted. Against the human data set, the strip-of-hydrophobic helix algorithm [Stille et al., Molec. Immun. 24, 1021-1027 (1987)] was the only significant predictor (p < 0.05), whereas against murine data only, the Roth2 pattern [Rothbard and Taylor, EMBO J. 7, 93-100 (1988)] was significant (p < 0.05). Not only were the majority of algorithms no better than random against both data sets, against the murine data two schemes were significant (p < 0.05) anti-predictors. This report indicates which predictors are relevant statistically and is the first to describe anti-predictors which can themselves be useful in the identification of T-cell epitopes.

Algorithms↗

PubMed2006

Predictors for response to rehabilitation in patients with hip or knee osteoarthritis: a comparison of logistic regression models with three different definitions of responder.

OBJECTIVE: To identify pre-treatment predictors of who will benefit from a 3-4-week comprehensive rehabilitation intervention in patients with osteoarthritis (OA) of the knee or hip. METHODS: A prospective cohort study with assessments at admission to the clinic and after 6 months was conducted. Two hundred and fifty patients from the rehabilitation clinic Rehaclinic Zurzach, Switzerland, were included. Three different measures of response to a 3-4-week comprehensive rehabilitation intervention were used: one indirect measure (minimal clinically important difference (MCID) in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) global score=18% improvement), one direct measure (transition question) and a combination of both criteria. Responders were predicted by a sequential logistic regression analysis with nine personal variables, five lifestyle risk factors, seven psychological status variables and the WOMAC global baseline score. RESULTS: The set of statistically significant predictors was dependent on the definition of response. The comparison of predictors that were statistically significant in any of the prediction models showed similar odds ratios (ORs) for the majority of predictors across three regression models with the different response definitions as dependent variable. Female gender, absence of depressive symptoms (dep), history of complementary medicine (cm) and low comorbidity (com) were the most stable predictors and had ORs above 2.0 (female) and above 1.5 (dep, cm, com) across the three regression models with different response definitions. CONCLUSION: A set of predictors for the outcome of rehabilitation in patients with OA was identified. If these predictors could be confirmed in future research, this knowledge might help to adopt and individualize the treatment of patients who are, at present, less likely to respond.

Aged↗

PubMed1998

Ultrasonographic and clinical predictors of intussusception.

OBJECTIVE: The objective of this study was to determine the positive and negative clinical predictors of intussusception and the correlation of ultrasonography and air enema in establishing this diagnosis. STUDY DESIGN: This was a prospective descriptive cohort study. SETTING: This study was performed in a tertiary care pediatric emergency department. PARTICIPANTS: Eighty-eight of 245 candidates were assessed for clinical predictors of intussusception. All 245 cases were examined for correlation between ultrasonography and air enema. INTERVENTIONS: A questionnaire, ultrasonography, and air enema were used. RESULTS: Thirty-five of the 88 patients assessed for clinical predictors were positive for intussusception. Significant positive predictors were right upper quadrant abdominal mass (positive predictive value [PPV] 94%), gross blood in stool (PPV 80%), blood on rectal examination (PPV 78%), the triad of intermittent abdominal pain, vomiting, and right upper quadrant abdominal mass (PPV 93%, p = 0.0001), and the triad with occult or gross blood per rectum (PPV 100%, p = not significant). Significant negative predictors were a combination of > or = 3 of 10 clinically significant negative features (negative predictive value 77%, p = 0.035). Of the total 245 cases, intussusception (as confirmed by doughnut, target, or pseudokidney sign) was ruled out by ultrasonography in 97.4%. Alternate ultrasound findings comprised 27% of negative cases. CONCLUSIONS: Excellent positive predictors of intussusception were identified prospectively. Although no reliable negative predictors were found, patients at low risk may be screened by ultrasonography.

Air↗