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Background: The System Usability Scale (SUS) is used to measure usability of internet-based Cognitive Behavioural Therapy (iCBT). However, whether the SUS is a valid instrument to measure usability in this context is unclear. The aim of this study is to assess the factor structure of the SUS, measuring usability of iCBT for depression in a sample of professionals. In addition, the psychometric properties (reliability, convergent validity) of the SUS were tested., Methods: A sample of 242 professionals using iCBT for depression from 6 European countries completed the SUS. Confirmatory Factor Analysis (CFA) was conducted to test whether a one-factor, two-factor, tone-model or bi-direct model would fit the data best. Reliability was assessed using complementary statistical indices (e.g. omega). To assess convergent validity, the SUS total score was correlated with an adapted Client Satisfaction Questionnaire (CSQ-3)., Results: CFA supported the one-factor, two-factor and tone-model, but the bi-factor model fitted the data best (Comparative Fit Index = 0.992, Tucker Lewis Index = 0.985, Root Mean Square Error of Approximation = 0.055, Standardized Root Mean Square Residual = 0.042 (respectively χ 2 diff (9) = 69.82, p < 0.001; χ 2 diff (8) = 33.04, p < 0.001). Reliability of the SUS was good (ω = 0.91). The total SUS score correlated moderately with the CSQ-3 (CSQ1 r s  = .49, p < 0.001; CSQ2 r s  = .46, p < 0.001; CSQ3 r s  = .38, p < 0.001), indicating convergent validity., Conclusions: Although the SUS seems to have a multidimensional structure, the best model showed that the total sumscore of the SUS appears to be a valid and interpretable measure to assess the usability of internet-based interventions when used by professionals in mental healthcare.

We report a case of cavitary pneumonia caused by N. otitidiscaviarum in a man with diabetes mellitus and thrombocytopenia treated with systemic corticosteroid. Taxonomic identification involved phenotypic testing and molecular identification that was carried out by DNA sequencing of the 16SrRNA gene.

One pre- and two postoperative cultures of tracheo-bronchial secretions were obtained from 28 cardiac patients, subjected to open-heart surgery. Four patients received preoperative antibiotics, and all but one received postoperative prophylactic antibiotics. Preoperatively, only one patient had potential pathogens; after surgery (mean intubation time 4.2 h), four patients (14.3%) had organisms; and after 19 h of intubation, 28% of the patients had potential pathogens in their tracheo-bronchial secretions. Only three of the seven organisms recovered from the last sample were clearly sensitive to the antibiotics given prophylactically; and two of these organisms were Group A beta-haemolytic streptococci. The early presence of organisms in the airways after intubation, the high incidence of colonization, and the ineffectiveness of prophylactic antibiotics in preventing this contamination are pointed out. The factors that may possibly influence colonization of airways among these patients are commented on.