Reliability and validity of a Portuguese version of the Young Mania Rating Scale

The reliability and validity of a Portuguese version of the Young Mania Rating Scale were evaluated. The original scale was translated into and adapted to Portuguese by the authors. Definitions of clinical manifestations, a semi-structured anchored interview and more explicit rating criteria were added to the scale. Fifty-five adult subjects, aged 18 to 60 years, with a diagnosis of Current Manic Episode according to DSM-III-R criteria were assessed using the Young Mania Rating Scale as well as the Brief Psychiatric Rating Scale in two sessions held at intervals from 7 to 10 days. Good reliability ratings were obtained, with intra-class correlation coefficient of 0.97 for total scores, and levels of agreement above 0.80 (P < 0.001) for all individual items. Internal consistency analysis resulted in an alpha = 0.67 for the scale as a whole, and an alpha = 0.72 for each standardized item (P < 0.001). For the concurrent validity, a correlation of 0.78 was obtained by the Pearson coefficient between the total scores of the Young Mania Rating Scale and Brief Psychiatric Rating Scale. The results are similar to those reported for the English version, indicating that the Portuguese version of the scale constitutes a reliable and valid instrument for the assessment of manic patients.

The validity and 4-year test-retest reliability of the Brazilian version of the Eating Attitudes Test-26

In a cross-sectional study conducted four years ago to assess the validity of the Brazilian version of the Eating Attitudes Test-26 (EAT-26) for the identification of abnormal eating behaviors in a population of young females in Southern Brazil, 56 women presented abnormal eating behavior as indicated by the EAT-26 and the Edinburgh Bulimic Investigation Test. They were each matched for age and neighborhood to two normal controls (N = 112) and were re-assessed four years later with the two screening questionnaires plus the Composite International Diagnostic Interview (CIDI). The EAT results were then compared to diagnoses originating from the CIDI. To evaluate the temporal stability of the two screening questionnaires, a test-retest design was applied to estimate kappa coefficients for individual items. Given the prevalence of eating disorders of 6.2%, the CIDI psychiatry interview was applied to 161 women. Of these, 0.6% exhibited anorexia nervosa and 5.6%, bulimia nervosa (10 positive cases). The validity coefficients of the EAT were: 40% sensitivity, 84% specificity, and 14% positive predictive value. Cronbach's coefficient was 0.75. For each EAT item, the kappa index was not higher than 0.344 and the correlation coefficient was lower than 0.488. We conclude that the EAT-26 exhibited low validity coefficients for sensitivity and positive predictive value, and showed a poor temporal stability. It is reasonable to assume that these results were not influenced by the low prevalence of eating disorders in the community. Thus, the results cast doubts on the ability of the EAT-26 test to identify cases of abnormal eating behaviors in this population.

Cost-effective analysis of different algorithms for the diagnosis of hepatitis C virus infection

We compared the cost-benefit of two algorithms, recently proposed by the Centers for Disease Control and Prevention, USA, with the conventional one, the most appropriate for the diagnosis of hepatitis C virus (HCV) infection in the Brazilian population. Serum samples were obtained from 517 ELISA-positive or -inconclusive blood donors who had returned to Fundação Pró-Sangue/Hemocentro de São Paulo to confirm previous results. Algorithm A was based on signal-to-cut-off (s/co) ratio of ELISA anti-HCV samples that show s/co ratio ³95% concordance with immunoblot (IB) positivity. For algorithm B, reflex nucleic acid amplification testing by PCR was required for ELISA-positive or -inconclusive samples and IB for PCR-negative samples. For algorithm C, all positive or inconclusive ELISA samples were submitted to IB. We observed a similar rate of positive results with the three algorithms: 287, 287, and 285 for A, B, and C, respectively, and 283 were concordant with one another. Indeterminate results from algorithms A and C were elucidated by PCR (expanded algorithm) which detected two more positive samples. The estimated cost of algorithms A and B was US$21,299.39 and US$32,397.40, respectively, which were 43.5 and 14.0% more economic than C (US$37,673.79). The cost can vary according to the technique used. We conclude that both algorithms A and B are suitable for diagnosing HCV infection in the Brazilian population. Furthermore, algorithm A is the more practical and economical one since it requires supplemental tests for only 54% of the samples. Algorithm B provides early information about the presence of viremia.

Comparison of the reliability of multifocal visual evoked cortical potentials generated by pattern reversal and pattern pulse stimulation

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.

Reliability and validity of heart rate variability threshold assessment during an incremental shuttle-walk test in middle-aged and older adults

Studies on the assessment of heart rate variability threshold (HRVT) during walking are scarce. We determined the reliability and validity of HRVT assessment during the incremental shuttle walk test (ISWT) in healthy subjects. Thirty-one participants aged 57 ± 9 years (17 females) performed 3 ISWTs. During the 1st and 2nd ISWTs, instantaneous heart rate variability was calculated every 30 s and HRVT was measured. Walking velocity at HRVT in these tests (WV-HRVT1 and WV-HRVT2) was registered. During the 3rd ISWT, physiological responses were assessed. The ventilatory equivalents were used to determine ventilatory threshold (VT) and the WV at VT (WV-VT) was recorded. The difference between WV-HRVT1 and WV-HRVT2 was not statistically significant (median and interquartile range = 4.8; 4.8 to 5.4 vs4.8; 4.2 to 5.4 km/h); the correlation between WV-HRVT1 and WV-HRVT2 was significant (r = 0.84); the intraclass correlation coefficient was high (0.92; 0.82 to 0.96), and the agreement was acceptable (-0.08 km/h; -0.92 to 0.87). The difference between WV-VT and WV-HRVT2 was not statistically significant (4.8; 4.8 to 5.4 vs 4.8; 4.2 to 5.4 km/h) and the agreement was acceptable (0.04 km/h; -1.28 to 1.36). HRVT assessment during walking is a reliable measure and permits the estimation of VT in adults. We suggest the use of the ISWT for the assessment of exercise capacity in middle-aged and older adults.

Differentiating origins of outflow tract ventricular arrhythmias: a comparison of three different electrocardiographic algorithms

Our objective is to evaluate the accuracy of three algorithms in differentiating the origins of outflow tract ventricular arrhythmias (OTVAs). This study involved 110 consecutive patients with OTVAs for whom a standard 12-lead surface electrocardiogram (ECG) showed typical left bundle branch block morphology with an inferior axis. All the ECG tracings were retrospectively analyzed using the following three recently published ECG algorithms: 1) the transitional zone (TZ) index, 2) the V2 transition ratio, and 3) V2 R wave duration and R/S wave amplitude indices. Considering all patients, the V2 transition ratio had the highest sensitivity (92.3%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (93.9%). The latter finding had a maximal area under the ROC curve of 0.925. In patients with left ventricular (LV) rotation, the V2 transition ratio had the highest sensitivity (94.1%), while the R wave duration and R/S wave amplitude indices in V2 had the highest specificity (87.5%). The former finding had a maximal area under the ROC curve of 0.892. All three published ECG algorithms are effective in differentiating the origin of OTVAs, while the V2 transition ratio, and the V2 R wave duration and R/S wave amplitude indices are the most sensitive and specific algorithms, respectively. Amongst all of the patients, the V2 R wave duration and R/S wave amplitude algorithm had the maximal area under the ROC curve, but in patients with LV rotation the V2 transition ratio algorithm had the maximum area under the ROC curve.

RELIABILITY AND SOCIAL KNOWLEDGERELEVANT RESPONSIBILITY

Knowledge seems to need the admixture of de facto reliability and epistemic responsibility. But philosophers have had a hard time in attempting to combine them in order to achieve a satisfactory account of knowledge. In this paper I attempt to find a solution by capitalizing on the real and ubiquitous human phenomenon that is the social dispersal of epistemic labour through time. More precisely, the central objective of the paper is to deliver a novel and plausible social account of knowledge-relevant responsibility and to consider the merits of the proposed combination of reliability and responsibility with respect to certain cases of unreflective epistemic subjects.