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31.
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Introduction: The Sustained Attention to Response Task (SART) helps to quantify vigilance impairments. Previous studies, in which five SART sessions on one day were administered, demonstrated worse performance during the first session than during the others. The present study comprises two experiments to identify a cause of this phenomenon. Method: Experiment 1, counting eighty healthy participants, assessed effects of repetition, napping, and time of day on SART performance through a between-groups design. The SART was performed twice in the morning or twice in the afternoon; half of the participants took a 20-minute nap before the second SART. A strong correlation between error count and reaction time (RT) suggested effects of test instruction. Participants gave equal weight to speed and accuracy in Experiment 1; therefore, results of 20 participants were compared to those of 20 additional participants who were told to prefer accuracy (Experiment 2). Results: The average SART error count in Experiment 1 was 10.1; the median RT was 280 ms. Neither repetition nor napping influenced error count or RT. Time of day did not influence error count, but RT was significantly longer for morning than for afternoon SARTs. The additional participants in Experiment 2 had a 49% lower error count and a 14% higher RT than the participants in Experiment 1. Error counts reduced by 50% from the first to the second session of Experiment 2, irrespective of napping or time of day. Conclusions: Preferring accuracy over speed was associated with a significantly lower error count. The data suggest that a worse performance in the first SART session only occurs when instructing participants to prefer accuracy, which is caused by repetition, not by napping or time of day. Note: We advise that participants are instructed to prefer accuracy over speed when performing the SART and that a full practice session is included.  相似文献   
33.
《Sleep medicine》2014,15(1):138-143
BackgroundThe status of night-to-night variability for periodic limb movements in sleep (PLMS) has not been clarified. With this in mind, we investigated the validity of PLMS measurement by actigraphy with the PAM-RL device in Japanese patients with suspected restless legs syndrome (RLS) or periodic limb movement disorder (PLMD) and the night-to-night variability of PLMS among the subjects.MethodsForty-one subjects (mean age, 52.1 ± 16.1 years) underwent polysomnography (PSG) and PAM-RL measurement simultaneously. Thereafter, subjects used the PAM-RL at home on four more consecutive nights.ResultsThe correlation between PLMS index on PSG (PLMSI-PSG) and PLM index on PAM-RL (PLMI-PAM) was 0.781 (P < .001). When the PLMSI cutoff value on PSG was set at 15 episodes per hour, the cutoff value for predicting this PLMSI level was 16.0 episodes per hour. When the condition was set to the level in which the mean interclass correlation coefficient reached ⩾0.9, the number of required nights for repeated measurements was 26 nights for subjects with PLMI of <15 episodes per hour and three nights for those with PLMI ⩾15 episodes per hour on PAM-RL.ConclusionsPAM-RL is thought to be valuable for assessing PLMS even in Japanese subjects. Recording of PAM-RL for three or more consecutive nights may be required to ensure the screening reliability of a patient with suspected pathologically frequent PLMS.  相似文献   
34.
The current study aimed at developing and conducting a preliminary validation a novel social functioning measure for people with early psychosis. The First Episode Social Functioning Scale (FESFS) was developed to cover many domains specific to this population in their contemporary reality. The self-report version of the FESFS was administered to 203 individuals receiving services in first episode clinics. Scores of the GAF, SOFAS, Social Functioning Scale and BPRS were also obtained for parts of the sample to calculate convergent and discriminant validity. A subgroup also answered the FESFS at several time points during treatment in order to determine sensibility to change. Principal component factor analyses and internal consistency analyses revealed the following nine factors with alphas ranging from 0.63 to 0.80: Friendships and social activities, Independent living skills, Interacting with people, Family, Intimacy, Relationships and social activities at work, Work abilities, Relationships and social activities at school, Educational abilities. Convergent and discriminant validity were demonstrated, as well as sensitivity to change. Clinical and research utility of the FESFS are discussed.  相似文献   
35.
ObjectiveExisting instruments for assessing health literacy skills in parents have limited scope to inform the design and evaluation of health literacy interventions. In this study we aimed to develop and validate a new performance-based measure of health literacy for Australian parents, the Parenting Plus Skills Index (PPSI). The instrument aimed to assess functional, communicative and critical health literacy skills.MethodsThe PPSI was developed in three phases: 1) Modified Delphi Expert Panel to provide feedback on 34 initial items; 2) Evaluation of psychometric properties of each item using a multidimensional item response theory model in a sample of Australian adults of parenting age (20−44 years) (N = 500); 3) Assessment of subset of items in an independent sample (N = 500).ResultsFollowing the three phases, 13 items were included in the final instrument. Participants scored on average 8.9/13 (69 %). The instrument demonstrated acceptable reliability (r = 0.70) and was significantly correlated with other performance-based health literacy instruments.ConclusionsThe PPSI is a validated 13-item performance-based instrument that assesses health literacy skills for parents in an Australian setting.Practice implicationsThe PPSI fills an important gap in available health literacy instruments that may be useful for facilitating development and evaluation of health literacy interventions.  相似文献   
36.
ObjectiveLegionella pneumophila serogroup 1 (Lp1) sequence type (ST) 1 is globally widespread in the environment and accounts for a significant proportion of Legionella infections, including nosocomial Legionnaires' disease (LD). This study aimed to design a sensitive and specific detection method for Lp ST1 that will underpin epidemiological investigations and risk assessment.MethodsA total of 628 Lp genomes (126 ST1s) were analyzed by comparative genomics. Interrogation of more than 900 accessory genes revealed seven candidate targets for specific ST1 detection and specific primers and hydrolysis probes were designed and evaluated. The analytical sensitivity and specificity of the seven primer and probe sets were evaluated on serially diluted DNA extracted from the reference strain CIP107629 and via qPCR applied on 200 characterized isolates. The diagnostic performance of the assay was evaluated on 142 culture-proven clinical samples from LD cases and a real-life investigation of a case cluster.ResultsOf seven qPCR assays that underwent analytical validation, one PCR target (lpp1868) showed higher sensitivity and specificity for ST1 and ST1-like strains. The diagnostic performance of the assay using respiratory samples corresponded to a sensitivity of 95% (19/20) (95% CI (75.1–99.9)) and specificity of 100% (122/122) (95% CI (97–100)). The ST1 PCR assay could link two out of three culture-negative hospitalized LD cases to ST1 during a real-time investigation.ConclusionUsing whole genome sequencing (WGS) data, we developed and validated a sensitive and specific qPCR assay for the detection of Lp1 belonging to the ST1 clonal complex by amplification of the lpp1868 gene. The ST1 qPCR is expected to deliver an added value for Lp control and prevention, in conjunction with other recently developed molecular assays.  相似文献   
37.
BackgroundImproving healthcare for people with chronic conditions requires clinical information systems that support integrated care and information exchange, emphasizing a semantic approach to support multiple and disparate Electronic Health Records (EHRs). Using a literature review, the Australian National Guidelines for Type 2 Diabetes Mellitus (T2DM), SNOMED-CT-AU and input from health professionals, we developed a Diabetes Mellitus Ontology (DMO) to diagnose and manage patients with diabetes. This paper describes the manual validation of the DMO-based approach using real world EHR data from a general practice (n = 908 active patients) participating in the electronic Practice Based Research Network (ePBRN).MethodThe DMO-based algorithm to query, using Semantic Protocol and RDF Query Language (SPARQL), the structured fields in the ePBRN data repository were iteratively tested and refined. The accuracy of the final DMO-based algorithm was validated with a manual audit of the general practice EHR. Contingency tables were prepared and Sensitivity and Specificity (accuracy) of the algorithm to diagnose T2DM measured, using the T2DM cases found by manual EHR audit as the gold standard. Accuracy was determined with three attributes – reason for visit (RFV), medication (Rx) and pathology (path) – singly and in combination.ResultsThe Sensitivity and Specificity of the algorithm were 100% and 99.88% with RFV; 96.55% and 98.97% with Rx; and 15.6% and 98.92% with Path. This suggests that Rx and Path data were not as complete or correct as the RFV for this general practice, which kept its RFV information complete and current for diabetes. However, the completeness is good enough for this purpose as confirmed by the very small relative deterioration of the accuracy (Sensitivity and Specificity of 97.67% and 99.18%) when calculated for the combination of RFV, Rx and Path. The manual EHR audit suggested that the accuracy of the algorithm was influenced by data quality such as incorrect data due to mistaken units of measurement and unavailable data due to non-documentation or documented in the wrong place or progress notes, problems with data extraction, encryption and data management errors.ConclusionThis DMO-based algorithm is sufficiently accurate to support a semantic approach, using the RFV, Rx and Path to define patients with T2DM from EHR data. However, the accuracy can be compromised by incomplete or incorrect data. The extent of compromise requires further study, using ontology-based and other approaches.  相似文献   
38.
Temporomandibular disorders (TMD) screeners assume significant item overlap with the screening questionnaire proposed by the American Academy of Orofacial Pain (AAOP).

Objective

To test the reliability and validity of the Portuguese version of AAOP questions for TMD screening among adolescents.

Material and Methods

Diagnoses from Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I were used as reference standard. Reliability was evaluated by internal consistency (KR-20) and inter-item correlation. Validity was tested by sensitivity, specificity, predictive values, accuracy and receiver operating characteristic (ROC) curves, the relationship between the true-positive rate (sensitivity) and the false-positive rate (specificity). Test-retest reliability of AAOP questions and intra-examiner reproducibility of RDC/TMD Axis I were tested with kappa statistics.

Results

The sample consisted of 1307 Brazilian adolescents (56.8% girls; n=742), with mean age of 12.72 years (12.69 F/12.75 M). According to RDC/TMD, 397 [30.4% (32.7% F/27.3% M)] of adolescents presented TMD, of which 330 [25.2% (27.6% F/22.2% M)] were painful TMD. Because of low consistency, items #8 and #10 of the AAOP questionnaire were excluded. Remaining items (of the long questionnaire version) showed good consistency and validity for three positive responses or more. After logistic regression, items #4, #6, #7 and #9 also showed satisfactory consistency and validity for two or more positive responses (short questionnaire version). Both versions demonstrated excellent specificity (about 90%), but higher sensitivity for detecting painful TMD (78.2%). Better reproducibility was obtained for the short version (k=0.840).

Conclusions

The Portuguese version of AAOP questions showed both good reliability and validity for the screening of TMD among adolescents, especially painful TMD, according to RDC/TMD.  相似文献   
39.
Aims/IntroductionThe purpose of the present study was to quantify errors in the diagnosis of diabetes for use in the national database, using a sufficient population size.Materials and methodsA claims database constructed by the JMDC (Tokyo, Japan), using standardized disease classifications and anonymous record linkage, was used in this validation study. We included patients with health insurance claims data from April 2005 to March 2019 in the JMDC claims database. We excluded patients without a record of specific health checkups in Japan. Sample size calculation was based on a 5% prevalence of diabetes and 0.4% absolute accuracy (i.e., 1,250,000 individuals), to calculate the sensitivity, specificity, positive predictive value and negative predictive value.ResultsIn total, 2,999,152 patients were included in this study, of which 165,515 were classified as having diabetes based on specific health checkups (validation cohort prevalence of 5.5%). The newly devised algorithm had three elements – the diagnosis‐related codes for diabetes without suspected flag, the medication codes for diabetes and then these two codes on the same record – and yielded a sensitivity of 74.6%, positive predictive value of 88.4% and Kappa Index of 0.80 (the highest values).ConclusionsIn future claims database studies, our validated algorithms will be useful as diagnostic criteria for diabetes.  相似文献   
40.
Schizotypal traits represent the behavioral expression of vulnerability to psychosis in general population. Among the most widely used measurement instruments, we could find the Schizotypal Personality Questionnaire (SPQ) (Raine, 1991). However, some aspects of its psychometric quality have yet to be analyzed. The main goal of the present study was to gather new sources of validity evidence of the SPQ scores in non-clinical young adults. The final sample was made up of 1123 college students (M=20.3 years; S.D.=2.6). The study of the internal structure using exploratory factor analysis revealed that SPQ items were grouped in a theoretical structure of seven second-order factors. Confirmatory factor analyses showed that the four-factor model (Paranoid) displayed better goodness-of-fit indices than the other hypothetical dimensional models tested. More complex measurement models, such as those tested using second-order confirmatory factor analyses and Exploratory Structural Equation Modeling, also showed adequate goodness-of-fit indices. The reliability of the SPQ scores ranged from 0.80 to 0.91. A total of 11 items showed differential functioning by gender. Advances in psychosis phenotype measurement open up new horizons to understand the structure and content of schizotypy.  相似文献   
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