You-Shan Feng

Systematic literature review and validity evaluation of the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Functional Composite (MSFC) in patients with multiple sclerosis.

BackgroundThere are a number of instruments that describe severity and progression of multiple sclerosis and they are increasingly used as endpoints to assess the effectiveness of therapeutic interventions. We examined to what extent the psychometric properties of two accepted instruments – EDSS and MSFC – meet methodological standards and the value they have in clinical trials.MethodsWe conducted a systematic literature search in relevant databases [MEDLINE (PubMed), ISI Web of Science, EMBASE, PsycINFO & PSYNDEX, CINAHL] yielding 3,860 results. Relevant full-text publications were identified using abstract and then full-text reviews, and the literature was reviewed.ResultsFor evaluation of psychometric properties (validity, reliability, sensitivity of change) of EDSS and MSFC, 120 relevant full-text publications were identified, 54 of them assessed the EDSS, 26 the MSFC and 40 included both instruments. The EDSS has some documented weaknesses in reliability and sensitivity to change. The main limitations of the MSFC are learning effects and the z-scores method used to calculate the total score. However, the methodological criterion of validity applies sufficiently for both instruments.For use in clinical studies, we found the EDSS to be preferred as a primary and secondary outcome measure in recent studies (50 EDSS, 9 MSFC).ConclusionsRecognizing their strengths and weaknesses, both EDSS and MSFC are suitable to detect the effectiveness of clinical interventions and to monitor disease progression. Almost all publications identify the EDSS as the most widely used tool to measure disease outcomes in clinical trials. Despite some limitations, both instruments are accepted as endpoints and neither are discussed as surrogate parameters in identified publications. A great advantage of the EDSS is its international acceptance (e.g. by EMA) as a primary endpoint in clinical trials and its broad use in trials, enabling cross-study comparisons.

Self-perceived quality of life predicts mortality risk better than a multi-biomarker panel, but the combination of both does best

BackgroundAssociations between measures of subjective health and mortality risk have previously been shown. We assessed the impact and comparative predictive performance of a multi-biomarker panel on this association.MethodsData from 4,261 individuals aged 20-79 years recruited for the population-based Study of Health in Pomerania was used. During an average 9.7 year follow-up, 456 deaths (10.7%) occurred. Subjective health was assessed by SF-12 derived physical (PCS-12) and mental component summaries (MCS-12), and a single-item self-rated health (SRH) question. We implemented Cox proportional-hazards regression models to investigate the association of subjective health with mortality and to assess the impact of a combination of 10 biomarkers on this association. Variable selection procedures were used to identify a parsimonious set of subjective health measures and biomarkers, whose predictive ability was compared using receiver operating characteristic (ROC) curves, C-statistics, and reclassification methods.ResultsIn age- and gender-adjusted Cox models, poor SRH (hazard ratio (HR), 2.07; 95% CI, 1.34-3.20) and low PCS-12 scores (lowest vs. highest quartile: HR, 1.75; 95% CI, 1.31-2.33) were significantly associated with increased risk of all-cause mortality; an association independent of various covariates and biomarkers. Furthermore, selected subjective health measures yielded a significantly higher C-statistic (0.883) compared to the selected biomarker panel (0.872), whereas a combined assessment showed the highest C-statistic (0.887) with a highly significant integrated discrimination improvement of 1.5% (p < 0.01).ConclusionAdding biomarker information did not affect the association of subjective health measures with mortality, but significantly improved risk stratification. Thus, a combined assessment of self-reported subjective health and measured biomarkers may be useful to identify high-risk individuals for intensified monitoring.

L-Carnitine-supplementation in advanced pancreatic cancer (CARPAN) - a randomized multicentre trial

BackgroundCachexia, a >10% loss of body-weight, is one factor determining the poor prognosis of pancreatic cancer. Deficiency of L-Carnitine has been proposed to cause cancer cachexia.FindingsWe screened 152 and enrolled 72 patients suffering from advanced pancreatic cancer in a prospective, multi-centre, placebo-controlled, randomized and double-blinded trial to receive oral L-Carnitine (4 g) or placebo for 12 weeks. At entry patients reported a mean weight loss of 12 ± 2,5 (SEM) kg. During treatment body-mass-index increased by 3,4 ± 1,4% under L-Carnitine and decreased (−1,5 ± 1,4%) in controls (p < 0,05). Moreover, nutritional status (body cell mass, body fat) and quality-of-life parameters improved under L-Carnitine. There was a trend towards an increased overall survival in the L-Carnitine group (median 519 ± 50 d versus 399 ± 43 d, not significant) and towards a reduced hospital-stay (36 ± 4d versus 41 ± 9d,n.s.).ConclusionWhile these data are preliminary and need confirmation they indicate that patients with pancreatic cancer may have a clinically relevant benefit from the inexpensive and well tolerated oral supplementation of L-Carnitine.

Rückenschmerz und Sozialschicht bei Berufstätigen

BACKGROUND Little empirical evidence is available on differential associations between social status indicators and back pain in Germany. This study therefore systematically evaluated associations between different indicators of social status and back pain. METHODS In total 4,412 employed adults, aged 18 to 65 years participated in a postal survey in 5 regions of Germany. The point prevalence and 1-year prevalence of back pain were assessed as well as the level of disabling back pain. Educational level, professional category and household income served as measures of social status. Associations between social status and back pain have been assessed cross-sectionally using Poisson regression. RESULTS Educational level was the best predictor for back pain among the assessed social status indicators. Adults with a low educational level had almost a 4-fold risk of reporting disabling back pain compared to subjects with a high educational level. Associations were highest for disabling back pain and attenuated strongly over the point prevalence towards the 1-year prevalence. DISCUSSION Back pain cannot generally be regarded as a symptom of a low social status. However, social inequality is of major importance regarding the prediction of severe back problems. A better understanding of mediating factors is essential for the prevention and therapy.

[Back pain and social status among the working population: what is the association? Results from a German general population survey].

BACKGROUND Little empirical evidence is available on differential associations between social status indicators and back pain in Germany. This study therefore systematically evaluated associations between different indicators of social status and back pain. METHODS In total 4,412 employed adults, aged 18 to 65 years participated in a postal survey in 5 regions of Germany. The point prevalence and 1-year prevalence of back pain were assessed as well as the level of disabling back pain. Educational level, professional category and household income served as measures of social status. Associations between social status and back pain have been assessed cross-sectionally using Poisson regression. RESULTS Educational level was the best predictor for back pain among the assessed social status indicators. Adults with a low educational level had almost a 4-fold risk of reporting disabling back pain compared to subjects with a high educational level. Associations were highest for disabling back pain and attenuated strongly over the point prevalence towards the 1-year prevalence. DISCUSSION Back pain cannot generally be regarded as a symptom of a low social status. However, social inequality is of major importance regarding the prediction of severe back problems. A better understanding of mediating factors is essential for the prevention and therapy.

An exploration of the non-iterative time trade-off method to value health states

Abstract Time Trade‐Off (TTO) usually relies on “iteration,” which is susceptible to bias. Discrete Choice Experiment with duration (or DCETTO) is free of such bias, but respondents find this cognitively more challenging. This paper explores non‐iterative TTO with or without lead time: NI(LT)TTO. In NI(LT)TTO, respondents see a series of independent pairwise choices without iteration (similar to DCETTO), but one of the two scenarios always involves full health for a shorter duration (similar to TTO). We compare three different “types” of NI(LT)TTO relative to DCETTO. Each type is presented in two “modes”: (a) verbally tabulated (as in a DCE) and (b) with visual aids (as in a TTO). The study has 8 survey variants, each with 12 experimental choice tasks and a 13th task with a logically determined answer. Data on the 12 experimental choices from an online survey of 6,618 respondents are modelled, by variant, using conditional logistic regressions. The results indicate that NI(LT)TTO is feasible, but some relatively mild states appear to have implausibly low predicted values, and the range of predicted values is much narrower than in DCETTO. The presentation of NI(LT)TTO tasks needs further improvement.

Rückenschmerz und Sozialschicht bei Berufstätigen@@@Back pain and social status among the working population: Ergebnisse einer deutschen Bevölkerungsstichprobe@@@What is the association? Results from a German general population survey

BACKGROUND Little empirical evidence is available on differential associations between social status indicators and back pain in Germany. This study therefore systematically evaluated associations between different indicators of social status and back pain. METHODS In total 4,412 employed adults, aged 18 to 65 years participated in a postal survey in 5 regions of Germany. The point prevalence and 1-year prevalence of back pain were assessed as well as the level of disabling back pain. Educational level, professional category and household income served as measures of social status. Associations between social status and back pain have been assessed cross-sectionally using Poisson regression. RESULTS Educational level was the best predictor for back pain among the assessed social status indicators. Adults with a low educational level had almost a 4-fold risk of reporting disabling back pain compared to subjects with a high educational level. Associations were highest for disabling back pain and attenuated strongly over the point prevalence towards the 1-year prevalence. DISCUSSION Back pain cannot generally be regarded as a symptom of a low social status. However, social inequality is of major importance regarding the prediction of severe back problems. A better understanding of mediating factors is essential for the prevention and therapy.