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PubMed1986

Fetal surveillance in diabetic pregnancy. I. Predictive value of the nonstress test.

Ninety-nine consecutive diabetic pregnancies (101 infants) were monitored with altogether 2672 nonstress tests (NSTs) from about 30 weeks of gestation until parturition. In 96% of the women the last NST was performed within 2 days of delivery. Fifty-nine percent had normal NSTs throughout pregnancy. Only 3.7% of the 2 672 tests were classified as pathological. When performed within 2 days antepartum, a normal NST predicted the 1-min Apgar score to be greater than or equal to 7 in 92%, and at 5 and 10 min in 99%. When all NSTs ever performed were included, the predictive value improved to 100%. The baby's first cry within 1 min after birth was predicted in 96%. Furthermore, the predictive value of a normal NST regarding the absence of ominous intrapartum cardiotocographic (CTG) patterns, normal pulmonary function and normal metabolic balance, was about 80%. The perinatal mortality was 1%. The specificity was in general good (86-96%), whereas the predictive value of pathological tests and the sensitivity almost without exception were poor. It is concluded that the very low rate of pathological NSTs indicates that obstetric interventions were made soon after the occurrence of the first sign of fetal jeopardy. Only then, and with meticulous care, is it possible to obtain good results. A normal NST is an excellent predictor of a normal Apgar score at 5 and 10 min, and also very good for a normal 1-min Apgar and an early cry from the baby. The predictive value is quite acceptable concerning the intrapartum CTG and the neonatal course likewise regarding the pulmonary function and metabolic balance.(ABSTRACT TRUNCATED AT 250 WORDS)

Apgar Score↗
PubMed2005

The long-term predictive accuracy of the short synacthen (corticotropin) stimulation test for assessment of the hypothalamic-pituitary-adrenal axis.

CONTEXT: The high-dose short Synacthen (corticotropin) test (SST) is widely used to investigate suspected secondary adrenal insufficiency, but concern remains about falsely reassuring results. OBJECTIVE: Our objective was to evaluate the long-term safety of the SST. METHOD: We retrospectively evaluated the clinical outcome in 178 patients who achieved 30-min cortisol values in the lowest 15th percentile of normal healthy responses. Thirty patients were later excluded because of missing case notes (20 patients) or unsubstantiated pituitary pathology (10 patients). The remaining 148 patients were divided into two groups: group 1, patients with cortisol response between the 5th and 15th percentiles of normal response (551-635 nmol/liter, 98 patients); and group 2, patients with borderline response between the 2.5th and 5th percentiles (510-550 nmol/liter, 50 patients). Patients did not receive routine glucocorticoid therapy, but those in group 2 were advised to take hydrocortisone in case of intercurrent illness. RESULTS: The median follow-up period from the initial SST was 4.2 yr (range, 4 months to 7 yr). A total of 137 patients showed no clinical or biochemical evidence of adrenal insufficiency during follow-up. Of the remaining 11 patients, seven became hypoadrenal after subsequent pituitary surgery or radiotherapy, one patient in group 1 developed adrenal insufficiency at 2 yr, and one patient in group 2 developed adrenal insufficiency at 6 months. The other two patients who were in group 2 had clinical diagnostic uncertainty. CONCLUSION: The high-dose SST is safe for the purpose of excluding clinically significant secondary adrenal insufficiency and is indicated as the first line of investigation for this purpose.

Adenoma↗
PubMed2004

[Preoperative prediction of creatinine clearance by using serum creatinine].

BACKGROUND: Creatinine clearance (Ccr) is an efficient index of renal function. However, measurement of Ccr is not routinely performed for preoperative patients. To predict preoperative renal impairment, we estimated the preoperative Ccr by using serum creatinine (sCr) and other laboratory findings. METHODS: 702 patients served as the training samples and other 128 patients as the validation samples. (1) Values of sCr and BUN to predict lower Ccr levels were developed from the training samples. In the combination of sCr and BUN, we selected the optimal combination in receiver operating characteristics curve. This value was applied to the validation samples. (2) The predictive equation was derived from the training samples by multiple regression analysis, and it was compared with the equations previously reported. RESULTS: (1) The optimal sensitivity and specificity for predicting Ccr less than 30 ml x min(-1) x 1.48 m(-2) were 60% and 84%, respectively. (2) Among the equations to predict Ccr, our equation showed the highest correlation coefficient (r), and the smallest differences between predicted and measured Ccr. CONCLUSIONS: We determined the values of sCr and BUN to predict renal impairment and derived predictive equation. Our equation was the best to assess the preoperative renal function.

Blood Urea Nitrogen↗
PubMedDate not supplied

Predictive validity of the Q16 questionnaire: a comparison between reported symptoms and neurobehavioral tests.

The correspondence between the answers to the Q16 questions regarding memory and attention-concentration and relevant neurobehavioral performance test scores has been evaluated. The sensitivity, specificity and diagnostic validity of Q16 have been assessed, taking the relevant neurobehavioral test score as a reference diagnostic criterion, the lower quartile of performance being considered as a poor response. The group under study consisted of 74 volunteers (24 females), aged 40 years on average (SD:7.5) and recruited among styrene-exposed workers and healthy controls. The test battery included the logical memory (short- and long-term) and the verbal learning (short- and long-term) tests of the Wechsler Adult Intelligence Scale (WAIS). The answers to the Q16 questions were poorly related to the performance: self-perceived forgetfulness showed a limited agreement with the long-term logical memory test (r=-0.23, p<0.05). The number of false negatives (no symptom but low test scores) was generally high, giving rise to a very low sensitivity of the questionnaire, despite a relatively high specificity. Accordingly, the positive diagnostic validity was low (<30%), whereas the negative diagnostic validity was high (>80%). Different methods used to investigate subtle neurological changes give rise to inconsistencies between self-perceived disturbances and objective measurements of relevant functions. Owing to its low sensitivity and positive diagnostic value, the Q16 cannot be recommended as a screening tool among workers occupationally exposed to neurotoxic chemicals.

Adult↗
PubMed2002

[Comparison of two score models in predicting prognosis and renal outcome in acute renal failure].

OBJECTIVE: To compare the value of ATN-ISI (acute tubular necrosis-individual severity index) and APACHE II (acute physiology and chronic health evaluation) score models in predicting mortality and renal outcome in patients with acute renal failure (ARF). METHODS: 422 in-hospital patients with ARF were retrospectively analysed, the value in predicting prognosis and renal outcome of these two score models was compared. Renal outcome was observed three times, i.e. >or= 30 days, >or= 45 days and >or= 60 days after the occurrence of ARF and discriminant analysis was used in the study. RESULTS: The scores of the two models both correlated significantly with the mortality of patients with ARF. When ATN-ISI scores were >or= 0.85, the mortality was 100% and it was the same with APACHE II when the scores were >or= 35. The areas under ROC curve of APACHE II and ATN-ISI were 0.817 +/- 0.021 and 0.880 +/- 0.018 respectively, suggesting good model discriminantion. For the correctly classificated rate of renal outcome, ATN-ISI was better than APACHE II at any time. When ATN-ISI scores were >or= 0.75, patients were dialysis dependent. When the scores were >or= 0.58 but less than 0.75, the patient's renal function did not recover but was not dialysis dependent; when the scores were < 0.58, the patients's renal function would recover. When APACHE II scores were >or= 26, patients were dialysis dependent. There was no cut-off score point to separate renal function recovery from renal dysfunction. However, when APACHE II scores were <or= 22, 19.6% of the patients had renal dysfunction and 80.4% of them had renal function recovered. CONCLUSION: Both the score models are of value in predicting mortality and renal outcome in patients with ARF. ATN-ISI score model was better than APACHE II.

APACHE↗
PubMed2000

Frontotemporal dementia and neuropsychology: the value of missing values.

OBJECTIVE: To investigate the effect of missing values due to behavioural disturbances on the neuropsychological test profile in frontotemporal dementia (FTD). The neuropsychological examination of patients with FTD poses a methodological problem. In many patients it is impossible to administer a complete test battery, due to behavioural disturbances inherent to the disease. This study describes the test behaviour of patients with FTD, the number of missing values due to disturbed test behaviour, and its influence on neuropsychological test results. METHODS: Thirty one patients with probable FTD were administered a neuropsychological test battery including measures of memory, intelligence, and executive functioning. Moreover, patients were rated on a global deterioration scale and a test behaviour scale, constructed for this study. RESULTS: The more disturbing the test behaviour, the less tests were assessable, leading to many missing values. The most disturbing features were "positive symptoms" of FTD, such as perseveration and stimulus boundedness. The effect of test behaviour was largest for tests measuring executive functions and reasoning capabilities. The replacement of the missing values due to behavioural disturbances by the lowest score also showed the largest effect on tests of executive function and reasoning abilities. CONCLUSION: Data imputation of missing values due to test behaviour disturbances provides a more differentiated picture of cognitive deficits in FTD.

Adult↗
PubMed2000

Development and standardization of the Self-regulation Skills Interview (SRSI): a new clinical assessment tool for acquired brain injury.

The Self-regulation Skills Interview (SRSI) is a clinical tool designed to measure a range of metacognitive skills essential for rehabilitation planning, monitoring an individual's progress, and evaluating the outcome of treatment interventions. The results of the present study indicated that the SRSI has sound interrater reliability and test-retest reliability. A principle components analysis revealed three SRSI factors: Awareness, Readiness to Change, and Strategy Behavior. A comparison between a group of 61 participants with acquired brain injury (ABI) and a group of 43 non-brain-injured participants indicated that the participants with ABI had significantly lower levels of Awareness and Strategy Behavior, but that level of Readiness to Change was not significantly different between the two groups. The significant relationship observed between the SRSI factors and measures of neuropsychological functioning confirmed the concurrent validity of the scale and supports the value of the SRSI for post-acute assessment.

Adult↗
PubMed1994

Predictive value of blood clotting tests in cardiac surgical patients.

This study prospectively evaluated numerous tests of clotting function in 897 consecutive adult cardiac surgical patients over 18 months. This included coronary operation, valve replacement, and reoperative patients. The tests included activated clotting time, activated partial thromboplastin time, prothrombin time, thrombin time, fibrinogen, fibrin/fibrinogen degradation products, platelet count, and Duke's earlobe bleeding time. Other variables such as age, sex, and cardiopulmonary bypass duration were included in the multivariate analysis. Statistically significant correlations were found between 16-hour mediastinal drainage and activated partial thromboplastin time, fibrinogen, activated clotting time, fibrin/fibrinogen degradation products, platelet count, and prothrombin time. Scatter plots indicate that these relationships, although statistically significant, had little predictive value and were largely significant as a result of the large number of patients in each group, which permitted weak correlations to reach statistical significance. The best multivariate model constructed could explain only 12% of the observed variation in postoperative blood loss. Because the predictive values of the tests are so low, it does not appear sensible to screen patients routinely using these clotting tests shortly after cardiopulmonary bypass.

Adult↗
PubMed2000

Accuracy of regression equation prediction across the range of estimated premorbid IQ.

Linear regression is often used to predict psychological criterion variables such as premorbid IQ. The prevailing method of evaluating the accuracy of prediction indicates poor accuracy for both high and low criterion values. These results have led to the conclusion that the equations are not applicable for predicting scores beyond about one standard deviation from the mean. The apparent inaccuracy at the extremes, however, is an artifact of inappropriate analysis. An alternative analysis method is described and used to re-analyze two sets of data. Empirical results show that both high and low WAIS-R IQ scores, predicted using versions of the NART, agree with actual measured IQ scores as accurately as do predicted scores near the mean. In addition, confidence intervals were only 5% larger for more extreme predicted values than for values near the mean, which would be of minor clinical consequence. The practical constraint on prediction of extreme values arises not from the regression technique, but from the limited range of the predictor variable(s). The two reviewed IQ prediction equations would, however, have adequate range for a high percentage of individuals.

Humans↗
PubMed1999

Assessment in general practice: the predictive value of written-knowledge tests and a multiple-station examination for actual medical performance in daily practice.

This study compares the predictive values of written-knowledge tests and a standardized multiple-station examination for the actual medical performance of general practitioners (GPs) in order to select effective assessment methods to be used in quality-improvement activities. A comprehensive assessment was performed in four phases. First, 100 GPs from the southern part of the Netherlands were assessed by a general medical knowledge test and by a knowledge test on technical skills. Second, in order to check for time-order effects, participants were randomly divided into two groups of 50 each, comparable on scores of both knowledge tests and on professional characteristics. Finally, both groups went through a multiple station examination using standardized patients and a practice video assessment of real surgery, but in opposite orders. Consultations were videotaped and assessed by well-trained peer observers. The drop-out rate was 10%. In both groups the predictive value of medical knowledge tests, ranging from 0.43 to 0.56 (Pearson correlation disattenuated), proved to be comparable with the predictive value of the multiple-station examination for actual performance (0.33-0.59). The overall explained variance of scores of the practice video assessment, measured by multiple regression analysis with performance scores as dependent variables and scores on the knowledge tests and the multiple-station examination as independent variables was moderate (19%). A time-order effect showed in only one direction: from practice video assessment to the multiple-station examination. The GP's professional characteristics did not contribute to the explanation of variation in performance. Medical knowledge tests can predict actual clinical performance to the same extent as a multiple-station examination. Compared with a station examination, a knowledge test may be a good alternative method for assessment the procedures of a large number of practising GPs.

Clinical Competence↗
PubMed2001

Diagnostic value of skin-prick and patch tests and serum eosinophil cationic protein and cow's milk-specific IgE in infants with cow's milk allergy.

The diagnosis of cow's milk allergy is based on a clinical response to an elimination-challenge test with cow's milk. We studied the usefulness of the skin-prick and patch tests and measurement of cow's milk-specific IgE and eosinophil cationic protein in serum as diagnostic tools for cow's milk allergy in a cohort of 6209 unselected infants followed from birth for the development of cow's milk allergy. Of the 239 infants challenged with cow's milk, 118 showed a positive and 121 a negative response at a mean age of 6.9 months. A positive reaction to a skin-prick test with cow's milk (> or = 3 mm) was seen in 72 (61%) and 29 (24%) infants with positive and negative challenges, elevated serum cow's milk-specific IgE (> or = 0.7 kU/L) in 52 (45%) and 15 (13%) infants, a positive reaction to patch test with cow's milk protein fractions in 26 (26%) and eight (8%) infants, and elevated serum eosinophil cationic protein (> or = 20 microg/L) in 22 (21%) and seven (13%) infants, respectively. Parallel use of the four tests with the above-mentioned cut-off values correctly classified 73% of the infants with a sensitivity of 0.76 and a specificity of 0.67. An immediate reaction to cow's milk challenge correlated with skin prick test positivity and elevated serum milk-specific IgE, and tended to correlate with patch test positivity. No single test or parallel use of the four tests could predict the challenge outcome acceptably in this prospectively followed, unselected cohort of 6209 infants. A positive reaction to one or more tests needs to be confirmed by a challenge test and a negative response to all four tests does not rule out the possibility of cow's milk allergy.

Blood Proteins↗
PubMed2001

Pitfalls of irritant patch testing using different test chamber sizes.

BACKGROUND: Test chambers for irritant patch testing are usually larger than those used in allergic patch testing. In general, larger areas show stronger skin reactions than smaller areas. OBJECTIVE: This study investigated whether this difference is of practical relevance, when a model irritant is applied in small and large Finn chambers and evaluated by measurement of transepidermal water loss (TEWL). METHODS: Patch testing was performed with 2 concentrations of sodium lauryl sulfate (SLS) (0.25% and 0.5%) on forearms of healthy volunteers. Large (inner diameter, 12 mm) and small (inner diameter, 8 mm) chambers were used. RESULTS: A variance analysis (3 factors, 2-tailed) showed that the test outcome, as assessed by TEWL, was strongly dependent on SLS test concentration and test chamber size. The larger chambers gave approximately 30% to 50% higher values than the smaller. CONCLUSIONS: This may be explained by the fact that with the small chambers, the adjacent small area of nontreated skin was also assessed by the evaporimeter, biasing the results. A formula estimating TEWL value of the large chamber from values of the small chambers has been proposed.

Adolescent↗
PubMed1995

The predictive value of cerebrospinal fluid dynamic tests in patients with th idiopathic adult hydrocephalus syndrome.

OBJECTIVE: To evaluate the predictive value of the cerebrospinal fluid (CSF) tap test and CSF outflow conductance in the selection of patients with the idiopathic adult hydrocephalus syndrome, defined exclusively on a clinical basis, for shunt surgery. DESIGN: A prospective, consecutive case series. All patients were assessed before surgery and at 3 months after shunt placement. Preoperatively, CSF pressure, conductance, and CSF formation rate were assessed by a constant-pressure infusion method. Improvement in gait and cognitive functions after removal of CSF was noted (ie, with the CSF tap test). Postoperatively, the infusion method was used to evaluate shunt function. SETTING: Tertiary, academic referral center. PATIENTS: Thirty-five patients with idiopathic adult hydrocephalus (normal-pressure hydrocephalus) syndrome based on conservative clinical criteria. No predictive tests were used for inclusion. All patients had a typical gait disturbance and a communicating hydrocephalus. Twenty-eight patients also had dementia or incontinence, or both. INTERVENTION: The CSF diversion (Cordis, [Orbis-Sigma]) valve, six patients; Hakim's standard system (Cordis Hakim standard system), 29 patients. OUTCOMES OF SURGERY: Serial videotaping of gait, a comprehensive neuropsychologic battery, and the Bartel index of activities of daily life. RESULTS: Gait was improved in 25 (72%) of the 35 patients, whereas the Bartel index remained unchanged. The conditions of five of seven patients with gait disturbance as the sole symptom improved. The spatial function (37% improved) and the findings from the Fuld object memory tests (29% improved) were significantly improved. Shunt dysfunction could not explain the lack of effect of an operation in the remaining patients. It should be noted that these results obtained at 3 months postoperatively may not be applicable in a long-term perspective. The CSF outflow conductance or CSF tap test were not able to identify those patients who would or would not benefit from a CSF diversion procedure. However patients had a lower conductance and a higher CSF pressure than did control subjects. CONCLUSIONS: Considerable improvement in gait was seen, but cognitive function was little affected. The CSF tap test or conductance does not provide additional information that is necessary to distinguish between patients whose conditions will or will not respond to shunting, when selection for surgery is based on conservative clinical criteria.

Activities of Daily Living↗
PubMedDate not supplied

Syphilis serology testing: a comparative study of Abbot Determine, Rapid Plasma Reagin (RPR) card test and Venereal Disease Research Laboratory (VDRL) methods.

Blood from 2100 women attending the antenatal clinic of the Port Moresby General Hospital (PMGH) and the 9 Mile urban clinic of Port Moresby was tested for syphili using the laboratory-based Venereal Disease Research Laboratory (VDRL) syphilis serology test and two clinic-based syphilis tests, Abbot Determine and Abbot Syfacard-RR (Rapid Plasma Reagin (RPR) card test). The Abbot Determine and the Syfacard-R tests were compared with the VDRL test, the gold standard in this study. The validation test results of Determine versus VDRL were as follows: sensitivity 92.0%; specificity 94.6%; the predictive value of a positive test 42.6%; and the predictive value of a negative test 99.6%. The validation tests for RPR versus VDRL were as follows: sensitivity 56.3% specificity 96.5%; predictive value of a positive test 41.2%; and the predictive value of a negative test 98.1%. The RPR test costs 3.5 kina (about one US dollar) a test, the VDRL less than 1 kina a test whilst the Determine test kit costs about 5 kina a test. When laboratory time, salaries and other supplies are costed the Determine test is expected to cost relatively much less. Our recommendation is that the Determine test be made available in areas of the country where VDRL is unavailable or where logistics do not allow for test results to be available early enough to make a difference to the care of th pregnant woman and her fetus.

Evaluation Studies as Topic↗