Risk factors contributing to symptomatic miniplate removal: a retrospective study of 153 bilateral sagittal split osteotomy patients

Removal of miniplates is a controversial topic in oral and maxillofacial surgery. Originally, miniplates were designed to be removed on completion of bone healing. The introduction of low profile titanium miniplates has led to the routine removal of miniplates becoming comparatively rare in many parts of the world. Few studies have investigated the reasons for non-routine removal of miniplates and the factors that affect osteosynthesis after osteotomy in large numbers of patients. The aim of the present study was to investigate complications related to osteosynthesis after bilateral sagittal split osteotomy (BSSO) in a large number (n=153) of patients. In addition to the rates of removal, emphasis was placed on investigating the reasons and risk factors associated with symptomatic miniplate removal. The rate of plate removal per patient was 18.6%, the corresponding rate per plate being 18.2%. Reasons for plate removal included plate-related complications in 16 patients and subjective discomfort in 13 patients. Half of the plates were removed during the first postoperative year. Smoking was the only significant predictor for plate removal. Patients undergoing orthognathic surgery should be screened with regard to smoking and encouraged and assisted to cease smoking, at least perioperatively.

Cross-reactivity in drug hypersensitivity reactions to sulfasalazine and sulfamethoxazole

Sulfonamides are generally classified into 2 groups: antibiotics and non-antibiotics. Recent studies showed that patients allergic to sulfonamide antibiotics do not have a specific risk for an allergy to sulfonamide non-antibiotic. However, the anti-inflammatory drug sulfasalazine represents an important exception. Used in rheumatic diseases, it is classified as a non-antibiotic sulfonamide, but is structurally related to antibiotic sulfonamides. Therefore, we aimed to analyze in vitro the cross-reactivity between the antimicrobial sulfamethoxazole and the anti-inflammatory drug sulfasalazine.

Dose escalation and pharmacokinetic study of AEZS-108 (AN-152), an LHRH agonist linked to doxorubicin, in women with LHRH receptor-positive tumors

Receptors for luteinizing hormone-releasing hormone (LHRH) can be utilized for targeted chemotherapy of cytotoxic LHRH analogs. The compound AEZS-108 (previously AN-152) consists of [D-Lys?]LHRH linked to doxorubicin. The objectives of this first study in humans with AESZ-108 were to determine the maximum tolerated dose and to characterize the dose-limiting toxicity, pharmacokinetics, preliminary efficacy, and hormonal effects.

Implicit and explicit evaluations: a declaration of dependence

This section presents abstracts of three studies on how consumer choices can be influenced by the name letter effect of brands without decision makers being aware of this influence. The first paper examined whether making brand names similar to consumers' names increases the likelihood that consumers will choose the brand. One prediction is that people will prefer and be more likely to choose products or services whose names prominently feature the letters in their own first or last names. The results showed that subjects' preference rankings and evaluations of name letter matching brands were higher than those of non-name letter matching brands. The second paper tested the possibility of using subliminal priming to activate a concept that a persuasive communicator could take advantage of. To examine the idea, two experiments were presented. In the first experiment, participants' level of thirst were manipulated and then subliminally presented them with either thirst-related words or control words. While the manipulations had no effect on participants' self-reported, conscious ratings of thirst, there was a significant interactive effect of the two factors on how much of the drink provided in the taste test was consumed. In a second, follow up experiment, thirsty participants were subliminally presented with either thirst-related words or control words after which they viewed advertisements for two new sports beverages. In conclusion, the research demonstrates that under certain conditions, subliminal printing techniques can enhance persuasion. The third paper hypothesized that the lack of correlations between implicit and explicit evaluations is due to measurement error.

Im Nebel der Präzision: die Bestimmung von GrenzfallkandidatInnen oder wie viel Reliabilität ist genug?

Hintergrund: Bei der Durchführung von summativen Prüfungen wird üblicherweise eine Mindestreliabilität von 0,8 gefordert. Bei praktischen Prüfungen wie OSCEs werden manchmal 0,7 akzeptiert (Downing 2004). Doch was kann man sich eigentlich unter der Präzision einer Messung mit einer Reliabilität von 0,7 oder 0,8 vorstellen? Methode: Mittels verschiedener statistischer Methoden wie dem Standardmessfehler oder der Generalisierbarkeitstheorie lässt sich die Reliabilität in ein Konfidenzintervall um eine festgestellte Kandidatenleistung übersetzen (Brennan 2003, Harvill 1991, McManus 2012). Hat ein Kandidat beispielsweise bei einer Prüfung 57 Punkte erreicht, schwankt seine wahre Leistung aufgrund der Messungenauigkeit der Prüfung um diesen Wert (z.B. zwischen 50 und 64 Punkte). Im Bereich der Bestehensgrenze ist die Messgenauigkeit aber besonders wichtig. Läge die Bestehensgrenze in unserem Beispiel bei 60 Punkten, wäre der Kandidat mit 57 Punkten zwar pro forma durchgefallen, allerdings könnte er aufgrund der Schwankungsbreite um seine gemessene Leistung in Wahrheit auch knapp bestanden haben. Überträgt man diese Erkenntnisse auf alle KandidatInnen einer Prüfung, kann man die Anzahl der Grenzfallkandidaten bestimmen, also all jene Kandidatinnen, die mit Ihrem Prüfungsergebnis so nahe an der Bestehensgrenze liegen, dass ihr jeweiliges Prüfungsresultate falsch positiv oder falsch negativ sein kann. Ergebnisse: Die Anzahl der GrenzfallkandidatInnen in einer Prüfung ist, nicht nur von der Reliabilität abhängig, sondern auch von der Leistung der KandidatInnen, der Varianz, dem Abstand der Bestehensgrenze zum Mittelwert und der Schiefe der Verteilung. Es wird anhand von Modelldaten und konkreten Prüfungsdaten der Zusammenhang zwischen der Reliabilität und der Anzahl der Grenzfallkandidaten auch für den Nichtstatistiker verständlich dargestellt. Es wird gezeigt, warum selbst eine Reliabilität von 0.8 in besonderen Situationen keine befriedigende Präzision der Messung bieten wird, während in manchen OSCEs die Reliabilität fast ignoriert werden kann. Schlussfolgerungen: Die Berechnung oder Schätzung der Grenzfallkandidaten anstatt der Reliabilität verbessert auf anschauliche Weise das Verständnis für die Präzision einer Prüfung. Wenn es darum geht, wie viele Stationen ein summativer OSCE benötigt oder wie lange eine MC-Prüfung dauern soll, sind Grenzfallkandidaten ein valideres Entscheidungskriterium als die Reliabilität. Brennan, R.L. (2003) Generalizability Theory. New York, Springer Downing, S.M. (2004) ‘Reliability: on the reproducibility of assessment data’, Medical Education 2004, 38, 1006–12 Harvill, L.M. (1991) ‘Standard Error of Measurement’, Educational Measurement: Issues and Practice, 33-41 McManus, I.C. (2012) ‘The misinterpretation of the standard error of measurement in medical education: A primer on the problems, pitfalls and peculiarities of the three different standard errors of measurement’ Medical teacher, 34, 569 - 76

An analysis of protocols and publications suggested that most discontinuations of clinical trials were not based on preplanned interim analyses or stopping rules.

OBJECTIVES To investigate the frequency of interim analyses, stopping rules, and data safety and monitoring boards (DSMBs) in protocols of randomized controlled trials (RCTs); to examine these features across different reasons for trial discontinuation; and to identify discrepancies in reporting between protocols and publications. STUDY DESIGN AND SETTING We used data from a cohort of RCT protocols approved between 2000 and 2003 by six research ethics committees in Switzerland, Germany, and Canada. RESULTS Of 894 RCT protocols, 289 prespecified interim analyses (32.3%), 153 stopping rules (17.1%), and 257 DSMBs (28.7%). Overall, 249 of 894 RCTs (27.9%) were prematurely discontinued; mostly due to reasons such as poor recruitment, administrative reasons, or unexpected harm. Forty-six of 249 RCTs (18.4%) were discontinued due to early benefit or futility; of those, 37 (80.4%) were stopped outside a formal interim analysis or stopping rule. Of 515 published RCTs, there were discrepancies between protocols and publications for interim analyses (21.1%), stopping rules (14.4%), and DSMBs (19.6%). CONCLUSION Two-thirds of RCT protocols did not consider interim analyses, stopping rules, or DSMBs. Most RCTs discontinued for early benefit or futility were stopped without a prespecified mechanism. When assessing trial manuscripts, journals should require access to the protocol.