The size of the treatment effect: do patients and proxies agree?

Background: This study examined whether MS patients and proxy respondents agreed on change in disease impact, which was induced by treatment. This may be of interest in situations when patients suffer from limitations that interfere with reliable self-assessment, such as cognitive impairment.Methods: MS patients and proxies completed the Multiple Sclerosis Impact Scale (MSIS-29) before and after intravenous steroid treatment. Analyses focused on patient-proxy agreement between MSIS-29 change scores. Transition ratings were used to measure the patient's judgement of change and whether this change was reflected in the MSIS-29 change of patients and proxies. Receiver operating characteristic (ROC) analyses were also performed to examine the diagnostic properties of the MSIS-29 when completed by patients and proxies.Results: 42 patients and proxy respondents completed the MSIS-29 at baseline and follow-up. Patient-proxy differences between change scores on the physical and psychological MSIS-29 subscale were quite small, although large variability was found. The direction of mean change was in concordance with the transition ratings of the patients. Results of the ROC analyses of the MSIS-29 were similar when completed by patients (physical scale: AUC = 0.79, 95% CI: 0.65 - 0.93 and 0.66, 95% CI: 0.48 - 0.84 for the psychological scale) and proxies (physical scale: 0.80, 95% CI: 0.72 - 0.96 and 0.71, 95% CI: 0.56 - 0.87 for the psychological scale)Conclusion: Although the results need to be further explored in larger samples, these results do point towards possible use of proxy respondents to assess patient perceived treatment change at the group level

Longitudinal proxy measurements in multiple sclerosis: patient-proxy agreement on the impact of MS on daily life over a period of two years

Background: The use of self- report measurements in clinical settings is increasing. However, in patients with limitations that interfere with reliable self- assessment such as cognitive impairment or mood disturbances, as may be the case in multiple sclerosis ( MS), data collection might be problematic. In these situations, information obtained from proxy respondents ( e. g. partners) may replace self- ratings. The aim of this study was to examine the value of proxy ratings at separate points in time and to assess patient- proxy agreement on possible changes in disease impact of MS. Methods: Fifty- six MS patients and their partners completed the Multiple Sclerosis Impact Scale ( MSIS- 29) at baseline and follow- up, two years later. Patient- proxy agreement was assessed at both time points by calculating intraclass correlation coefficients ( ICCs), exact and global agreement and the mean directional differences between groups. Agreement of change over time was assessed by calculating ICCs between change scores. In parallel, global ratings of both patients and proxy respondents of the extent to which the patient had improved or deteriorated over the past two years were collected to validate possible changes on the MSIS- 29. Results: At both time points, agreement on the physical scale was higher than agreement on the psychological scale ( ICCs at baseline were 0.81 for the physical scale and 0.72 for the psychological scale; at follow- up, the ICC values were 0.86 and 0.65 respectively). At follow- up, statistically significant mean differences between patients and proxies were noted for the physical scale (- 4.8 +/- 12.7, p = 0.006) and the psychological scale (- 8.9 +/- 18.8, p = 0.001). Agreement between change scores on the MSIS- 29 was fair ( ICC < 0.60). Our analyses suggest that the validity of measuring changes over time might be better for proxy respondents compared to patients. Conclusion: Proxy respondents could act as a reliable source of information in cross- sectional studies. Moreover, results suggested that agreement on change over time might be better for proxy respondents compared to patients. Although this remarkable finding should be interpreted cautiously because of several limitations of the study, it does plead for further investigation of this important topic

Towards computerizing intensive care sedation guidelines: design of a rule-based architecture for automated execution of clinical guidelines

<p>Abstract</p> <p>Background</p> <p>Computerized ICUs rely on software services to convey the medical condition of their patients as well as assisting the staff in taking treatment decisions. Such services are useful for following clinical guidelines quickly and accurately. However, the development of services is often time-consuming and error-prone. Consequently, many care-related activities are still conducted based on manually constructed guidelines. These are often ambiguous, which leads to unnecessary variations in treatments and costs.</p> <p>The goal of this paper is to present a semi-automatic verification and translation framework capable of turning manually constructed diagrams into ready-to-use programs. This framework combines the strengths of the manual and service-oriented approaches while decreasing their disadvantages. The aim is to close the gap in communication between the IT and the medical domain. This leads to a less time-consuming and error-prone development phase and a shorter clinical evaluation phase.</p> <p>Methods</p> <p>A framework is proposed that semi-automatically translates a clinical guideline, expressed as an XML-based flow chart, into a Drools Rule Flow by employing semantic technologies such as ontologies and SWRL. An overview of the architecture is given and all the technology choices are thoroughly motivated. Finally, it is shown how this framework can be integrated into a service-oriented architecture (SOA).</p> <p>Results</p> <p>The applicability of the Drools Rule language to express clinical guidelines is evaluated by translating an example guideline, namely the sedation protocol used for the anaesthetization of patients, to a Drools Rule Flow and executing and deploying this Rule-based application as a part of a SOA. The results show that the performance of Drools is comparable to other technologies such as Web Services and increases with the number of decision nodes present in the Rule Flow. Most delays are introduced by loading the Rule Flows.</p> <p>Conclusions</p> <p>The framework is an effective solution for computerizing clinical guidelines as it allows for quick development, evaluation and human-readable visualization of the Rules and has a good performance. By monitoring the parameters of the patient to automatically detect exceptional situations and problems and by notifying the medical staff of tasks that need to be performed, the computerized sedation guideline improves the execution of the guideline.</p

The Arm Function in Multiple Sclerosis Questionnaire (AMSQ): Development and validation of a new tool using IRT methods

Purpose: We developed the Arm Function in Multiple Sclerosis Questionnaire (AMSQ) to measure arm and hand function in MS, based on existing scales. We aimed at developing a unidimensional scale containing enough items to be used as an itembank. In this study, we investigated reliability and differential item functioning of the Dutch version. Method: Patients were recruited from two MS Centers and a Dutch website for MS patients. We performed item factor analysis on the polychoric correlation matrix, using multiple fit-indices to investigate model fit. The graded response model, an item response theory model, was used to investigate item goodness-of-fit, reliability of the estimated trait levels (θ), differential item functioning, and total information. Differential item functioning was investigated for type of MS, gender, administration version, and test length. Results: Factor analysis results suggested one factor. All items showed p-values of the item goodness-of-fit statistic above 0.0016. The reliability was 0.95, and no items showed differential item functioning on any of the investigated variables. Conclusion: AMSQ is a unidimensional 31-item questionnaire for measuring arm function in MS. Because of a well fit in a graded response model, it is suitable for further development as a computer adaptive test. ▸ Implications for Rehabilitation • A new questionnaire for arm and hand function recommended in people with multiple sclerosis (AMSQ). • Scale characteristics make the questionnaire suitable for use in clinical practice and research. • Good reliability. • Further development as a computer adaptive test to reduce burden of (repetitive) testing in patients is feasible

Comparison of Different RNAi Experiments of Chromosome I Using Wild-Type Bristol N2 and <i>rrf-3</i>

<p>Differences between different laboratories or investigators and between experiments done within the same laboratory and by the same investigators are observed. Ovals represent the amount of bacterial clones that gave an RNAi phenotype in an experiment. Areas that overlap represent clones for which in both experiments an RNAi phenotype was detected. Differences and overlap between an RNAi experiment done with the <i>rrf-3</i> mutant strain and the data obtained by <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0000012#pbio-0000012-Fraser1" target="_blank">Fraser et al. (2000</a>) done with the standard laboratory strain, Bristol N2 (A); N2 and <i>rrf-3</i> tested at the same time within our laboratory (B); experiments done with N2 in two different laboratories: this study (‘NL') and <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.0000012#pbio-0000012-Fraser1" target="_blank">Fraser et al. (2000</a>) (C); two experiments done with the same strain, <i>rrf-3</i>, within our laboratory (D).</p

Validation and interpretation of the Dutch version of the Multiple Sclerosis Neuropsychological Screening Questionnaire

AbstractBackgroundThe Multiple Sclerosis Neuropsychological Screening Questionnaire (MSNQ) was developed for screening of MS patients at risk for cognitive impairment with a patient self-report (MSNQ-P) and an informant version (MSNQ-I). The objective of this study was to validate the Dutch versions and determine their interpretability.MethodsThe MSNQ was completed by 121 MS patients and their partners (informants). We investigated the factor structure, internal consistency and construct validity. Interrater reliability between MNSQ-P and MSNQ-I was investigated with the intraclass correlation coefficient (ICC) and Cohen's kappa. For interpretability of both MSNQ versions we calculated sensitivity, specificity and cut-off scores. Receiver operating characteristic (ROC) curves with related area under the curve (AUC) were used to evaluate the added value of combining both versions.ResultsWe found a unidimensional factor structure. Cronbach's alphas were 0.93 and 0.94 for MSNQ-P and MSNQ-I, respectively. The ICC was 0.59 and kappas were ≤0.50. No cut-off score could be defined for the MSNQ-P because of low sensitivity. For the MSNQ-I, sensitivity was 0.75 and specificity 0.71 (AUC 0.80). The cut-off score was 21. ROC curve analyses showed no added value of the MSNQ-P when used in combination with the MSNQ-I.ConclusionsThe MSNQ-I is preferred over the MSNQ-P to screen MS patients for cognitive impairment