Jan Van Looy

Technological advancement has decreased network latencies while simultaneously increasing local latencies. This may impact exergames---video games that incorporate exercise---the most since exergames tend to have complicated platforms to capture player actions. This paper presents a study using a custom desktop-based exergame that controls for local latency and measures player performance and Quality of Experience (QoE). Analysis of the results from a 37-person user study shows that while player performance and quality of experience degrades with latency, exergame actions are fairly tolerant of even hundreds of milliseconds of latency. Our data point towards a crucial tipping point at latency values of approximately 400 milliseconds.

A multidisciplinary journal on gaming and gamification for health education/promotion, teaching and social change.

Journal of Medical Internet Research - International Scientific Journal for Medical Research, Information and Communication on the Internet #Preprint #PeerReviewMe: Warning: This is a unreviewed preprint. Readers are warned that the document has not been peer-reviewed by expert/patient reviewers or an academic editor, may contain misleading claims, and is likely to undergo changes before final publication, if accepted, or may have been rejected/withdrawn. Readers with interest and expertise are encouraged to sign up as peer-reviewer, if the paper is within an open peer-review period. Please cite this preprint only for review purposes or for grant applications and CVs (if you are the author). Background: The high incidence and relapse rates of major depressive disorder demand novel treatment options. Standard treatments (psychotherapy, medication) usually do not target cognitive control impairments, although these seem to play a crucial role in achieving stable remission. The urgent need for treatment combined with poor availability of adequate psychological interventions has instigated a shift toward internet interventions. Numerous computerized programs have been developed that can be presented online and offline. However, their uptake and adherence are oftentimes low. Objective: The aim of this study was to perform a user requirements analysis for an internet-based training targeting cognitive control. This training focuses on ameliorating cognitive control impairments, as these are still present during remission and can be a risk factor for relapse. To facilitate uptake of and adherence to this intervention, a qualitative user requirements analysis was conducted to map mandatory and desirable requirements. Methods: We conducted a user requirements analysis through a focus group with 5 remitted depressed individuals and individual interviews with 6 mental health care professionals. All qualitative data were transcribed and examined using a thematic analytic approach. Results: Results showed mandatory requirements for the remitted sample in terms of training configuration, technological and personal factors, and desirable requirements regarding knowledge and enjoyment. Furthermore, knowledge and therapeutic benefits were key requirements for therapists. Conclusions: The identified requirements provide useful information to be integrated in interventions targeting cognitive control in depression.

Journal of Medical Internet Research - International Scientific Journal for Medical Research, Information and Communication on the Internet #Preprint #PeerReviewMe: Warning: This is a unreviewed preprint. Readers are warned that the document has not been peer-reviewed by expert/patient reviewers or an academic editor, may contain misleading claims, and is likely to undergo changes before final publication, if accepted, or may have been rejected/withdrawn. Readers with interest and expertise are encouraged to sign up as peer-reviewer, if the paper is within an open peer-review period. Please cite this preprint only for review purposes or for grant applications and CVs (if you are the author). Background: The high incidence and relapse rates of major depressive disorder demand novel treatment options. Standard treatments (psychotherapy, medication) usually do not target cognitive control impairments, although these seem to play a crucial role in achieving stable remission. The urgent need for treatment combined with poor availability of adequate psychological interventions has instigated a shift toward internet interventions. Numerous computerized programs have been developed that can be presented online and offline. However, their uptake and adherence are oftentimes low. Objective: The aim of this study was to perform a user requirements analysis for an internet-based training targeting cognitive control. This training focuses on ameliorating cognitive control impairments, as these are still present during remission and can be a risk factor for relapse. To facilitate uptake of and adherence to this intervention, a qualitative user requirements analysis was conducted to map mandatory and desirable requirements. Methods: We conducted a user requirements analysis through a focus group with 5 remitted depressed individuals and individual interviews with 6 mental health care professionals. All qualitative data were transcribed and examined using a thematic analytic approach. Results: Results showed mandatory requirements for the remitted sample in terms of training configuration, technological and personal factors, and desirable requirements regarding knowledge and enjoyment. Furthermore, knowledge and therapeutic benefits were key requirements for therapists. Conclusions: The identified requirements provide useful information to be integrated in interventions targeting cognitive control in depression.

Standardization bodies recommend various protocols to conduct subjective quality assessment (QA) of imaging systems. While many studies have compared these QA protocols, few have assessed the impact of different approaches for preprocessing and analyzing quality ratings. Furthermore, the effect of large versus small quality differences on the discrimination performance of protocols has not been extensively studied in video QA. This study examines these issues for four QA protocols. H.264 compressed medical videos and denoised natural scene videos were evaluated by expert and naive subjects. Scores were collected with four QA protocols-forced choice (FC), two ratio-scaled paired comparison methods: preference (Pref) and dissimilarity (Dissim), and single stimulus (SS)-and analyzed using combinations of different rating preprocessing approaches, generating a total of 14 methods. Performance metrics-probability and effect size-quantified the ability of the methods to discriminate between quality levels. The Pref and Dissim methods analyzed with classical multidimensional scaling and the SS method with Z-score transformation consistently outperformed the other methods. The type of preprocessing introduced large differences in the performance of individual protocols. Grouping stimuli pairs by small and large quality differences introduced significant differences in the performance rankings of the methods, with Pref and Dissim being most sensitive to small quality differences. For the future, we suggest further validation of the FC method, due to its simplicity and ease of use, and continued investigation into more robust raw scores transformation and statistical analysis methods for both SS and FC ratings.