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.

strategy reduces the risk of overestimating adherence. For prescriptions extending beyond the end of the analysis period, days' supply is truncated at the end of the period. Patients in each study sample are stratified into 5 categories based on their adherence score: 1-19%, 20-39%, 40-59%, 60-79%, or 80-100 %. Results: High level of medication adherence was associated with lower hospitalization and exacerbation rates. ConClusions: Increased drug utilization can provide a net economic return when it is driven by improved adherence.

Diverse methods are available for evaluation of (medical) interventions. In each case one has to decide on a specific method. Our aim was to analyze typical problems involved in the measurement of change. Different methods are delineated, and their specific pros and cons are set out. Subsequently, empirically derived recommendations are outlined on which method should be employed for which problem and under which circumstances. A characteristic of rehab treatment is that as a rule a multitude of problems are addressed, and accordingly, treatment goals are heterogenic. Straightforward recommendations for one or the other method cannot be given.

In considering the 2 methods of measuring change, it is apparent that the standard method of change measurement (indirect change measurement) is suitable to reflect a comprehensive and multi-dimensional representation of changes within the field of medical rehabilitation evaluation.

Objectives: It is estimated that 30% of psoriasis (PSO) patients also develops psoriatic arthritis (PSA). This potential disease evolution brings along new symptoms such as swollen and painful joints and mobility problems. Since both diseases are potentially degenerative, the aim of this study was to measure which group of patients (PSO or PSA) is willing to pay most out of pocket to avoid their health related quality of life (HRQoL) to worsen. MethOds: 395 US patients diagnosed with either psoriasis (n= 151) or psoriatic arthritis (n= 247) completed a questionnaire as part of a broader survey of treatment of PSO/PSA. The questionnaire included the EQ-5D-5L instrument and accompanying VAS. Patients were additionally asked to indicate by reference to the EQ-5D VAS scale the amount of money per month they would be willing to pay for treatments that would prevent a decline in HRQoL by 10 points. Price sensitivity curves were created by means of linear regression analysis that predict the proportion of patients willing to pay a certain amount of $ out of pocket per month. Results: For both PSO (R² = 0,82) and PSA (R² = 0,86) monthly cost out of pocket (x-variable) was a good predictor of the proportion of patients that is willing to pay a certain amount out of pocket per month (y-variable). Regression models look as follows. For PSO: y = 0,77e -0,005x for PSA: y = 0,86e -0,007x . To give a specific example 42% of the PSA patients is willing to pay $100 per month out of pocket whereas this is 47% among PSO patients. cOnclusiOns: PSO patients are prepared to pay more out of pocket on a monthly basis to avoid their HRQoL to worsen than PSA patients. Further research is required to understand what drives this difference. PMS83Objectives: To report the long-term effect of certolizumab pegol (CZP) on workplace and household productivity up to 96 weeks (wks) in patients with axial spondyloarthritis (axSpA), including ankylosing spondylitis (AS, meeting modified New York criteria) and non-radiographic axSpA (nr-axSpA). MethOds: The ongoing RAPID-axSpA trial (NCT01087762), is double-blind and PBO-controlled to Wk24, dose-blind to Wk48 and open-label to Wk204. Patients had active axSpA, according to ASAS criteria, including AS and nr-axSpA patients. Patients originally randomized to CZP (200mg Q2W or 400mg Q4W, following 400mg loading dose [LD] at Wks 0, 2, 4) continued on their assigned dose in the OLE; PBO patients entering dose-blind phase were re-randomized to CZP LD followed by CZP 200mg Q2W or CZP 400mg Q4W after Wk24 or, for non-responders, after Wk16. The validated arthritis-specific Work Productivity Survey (WPS; administered Q4W) assessed the impact of axSpA on workplace and household productivity. WPS responses (LOCF imputation) in patients originally randomized to CZP are summarized descriptively over 96 wks. Results: 325 patients were randomized, of whom 218 received CZP (200mg Q2W or 400mg Q4W) from Wk0. Of patients randomized to CZP at baseline (BL), 93% completed Wk24, 88% Wk48 and 80% Wk96. At BL, 72% of CZP...