Äquivalenzprüfung bei impliziten und expliziten Motivmaßen anhand eines experimentellen Re-Test Designs

Wird der Vorgabemodus eines psychologisch-diagnostischen Verfahrens geändert, so muss vor der Verwendung der Normen der Ursprungsversion die Äquivalenz festgestellt werden. Ziel dieser Studie war es, die Äquivalenz einer Papier und Bleistift Testung (PBT) und einer PC-Testung bei impliziten und expliziten Motivmaßen zu untersuchen. Dafür wurde nach Wagner-Menghin (2003a) sowohl die psychometrische als auch die erfahrungspsychologische Äquivalenz ermittelt. Für die Erfassung der expliziten Motive wurde der PRF-D verwendet, die impliziten Motive wurden mit Hilfe des OMT erhoben. Zur Überprüfung der erfahrungsbezogene Äquivalenz diente eine Ratingskala. Beide Verfahren und die Ratingskala wurden insgesamt 177 Psychologie-Studenten der Universität Wien in einem experimentellen Retest Design vorgelegt. Die Ergebnisse zeigen, dass beim PRF-D nur die Reliabilität im Sinne der inneren Konsistenz einen signifikanten Unterschied ergibt (.72 in der PBT-Gruppe, .85 in der PC Gruppe). Die restlichen Werte der psychometrischen und erfahrungsbezogenen Äquivalenz weisen keinen signifikanten Unterschied auf. Beim OMT hingegen zeigt sich ein signifikanter Unterschied in der Skala „Leistung“ in den Mittelwerten, der Verteilung und der Rangreihung. Auch die erfahrungsbezogene Äquivalenz kann nicht als gegeben angenommen werden. Es zeigt sich wiederum die Notwendigkeit einer Äquivalenzprüfung bei einer Änderung des Vorgabemodus.When changing the mode of presentation of a psychological test, the equivalence of these two modes has to be verified before using the norms of the original. The goal of this study was to measure the equivalence between Paper and Pencil (PP) and Computer based tests (CBT) when it comes to measuring implicit and explicit motives. To do so, the approach of Wagner-Menghin (2003a) was used, hence the psychometric and the subjective equivalence were measured. For assessing the explicit motives the PRF-D was used, for assessing the implicit motives, the OMT was used. The subjective equivalence was obtained by a rating scale. 177 Psychology students were given both tests and the rating scale, using an experimental retest design. The findings show, that the PRF-D only differed in the internal consistency (.72 in the PP-Group and .85 in the CBT Group). The remaining values of the psychometric and the subjective equivalence did not differ significantly. The OMT on the other hand showed a significant difference in the scale “Achievement” in its means, the distribution and the ranked orders. The subjective equivalence cannot be assumed either. These findings again show the importance of verifying the equivalence when changing the mode of presentation

Optimal duration and combination of antiplatelet therapies following percutaneous coronary intervention: a meta-analysis.

Abstract Introduction The ideal duration of dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI) is still unknown. In this meta-analysis, we aimed to compare very short-term (1–3 months), short-term (6 months), standard-term (12 months) and long-term (>12 months) DAPT durations for efficacy and safety. Methods Overall DAPT comparisons were classified as "any shorter-term"/"any longer-term" DAPT. The primary outcome was a composite of major adverse cardiovascular events (MACE: non-fatal myocardial infarction, non-fatal stroke and cardiovascular death). The primary safety outcome was major bleeding. Results Twenty-six studies comprising 103.394 patients were included. Compared with standard-term DAPT duration, very short-term DAPT duration with subsequent drop of aspirin (RR 1.06, 95% CI, 0.95–1.18, p = 0.26) or drop of the P2Y12 inhibitor (RR 0.92, 95% CI, 0.72-1.16, p = 0.47) was not associated with a higher risk of MACE. Any longer-term compared with any shorter-term DAPT durations led to a significantly lower risk of MACE (RR 0.88, 95% CI, 0.81–0.96, p = 0.002), but a significantly higher risk of BARC 3-5 major bleeding events (RR 1.63, 95% CI, 1.22–2.17, p = 0.001). In the ACS subgroup receiving prasugrel or ticagrelor but not clopidogrel, any longer-term DAPT duration was associated with a significantly lower risk of MACE compared to any shorter-term DAPT duration (RR 0.84, 95% CI, 0.77–0.92, p = 0.0001). Conclusion DAPT may be shortened to 1-3 months in patients with low ischemic but high bleeding risk followed by aspirin or P2Y12 monotherapy. Prasugrel or ticagrelor based DAPT may be extended to >12 months in case of high ischemic and low bleeding risk. PROSPERO registration no CRD42020163719

The von Willebrand factor A-1 domain binding aptamer BT200 elevates plasma levels of von Willebrand factor and factor VIII: a first-in-human trial

Von Willebrand factor (VWF) and factor VIII (FVIII) circulate in a noncovalent complex in blood and promote primary hemostasis and clotting, respectively. A new VWF A1-domain binding aptamer, BT200, demonstrated good subcutaneous bioavailability and a long half-life in non-human primates. This first-in-human, randomized, placebo-controlled, doubleblind trial tested the hypothesis that BT200 is well tolerated and has favorable pharmacokinetic and pharmacodynamic effects in 112 volunteers. Participants received one of the following: a single ascending dose of BT200 (0.18-48 mg) subcutaneously, an intravenous dose, BT200 with concomitant desmopressin or multiple doses. Pharmacokinetics were characterized, and the pharmacodynamic effects were measured by VWF levels, FVIII clotting activity, ristocetin-induced aggregation, platelet function under high shear rates, and thrombin generation. The mean half-lives ranged from 7-12 days and subcutaneous bioavailability increased dose-dependently exceeding 55% for doses of 6-48 mg. By blocking free A1 domains, BT200 dose-dependently decreased ristocetin-induced aggregation, and prolonged collagen-adenosine diphosphate and shear-induced platelet plug formation times. However, BT200 also increased VWF antigen and FVIII levels 4-fold (P<0.001), without increasing VWF propeptide levels, indicating decreased VWF/FVIII clearance. This, in turn, increased thrombin generation and accelerated clotting. Desmopressin-induced VWF/FVIII release had additive effects on a background of BT200. Tolerability and safety were generally good, but exaggerated pharmacology was seen at saturating doses. This trial identified a novel mechanism of action for BT200: BT200 dose-dependently increases VWF/FVIII by prolonging half-life at doses well below those which inhibit VWF-mediated platelet function. This novel property can be exploited therapeutically to enhance hemostasis in congenital bleeding disorders