To my family Josefin, Selma and Oskar. Not only did they put up with me during the entire PhD journey, but they also spent the last two weeks of it in quarantine with me because of the coronavirus pandemic of 2020.ABSTRACT Background: Internet-delivered Cognitive Behavior Therapy (ICBT) is efficacious for a number of psychiatric disorders and can be successfully implemented in routine psychiatric care. Still, only about half of patients experience a good enough treatment outcome. Using data from the early part of treatment to identify patients with high risk of not benefitting from it, and target them with additional resources to prevent the predicted failure is a potential way forward. We call this an Adaptive Treatment Strategy, and a very important part of it is the ability to predict the outcome for a specific patient. Aims:To establish a proof of concept for an Adaptive Treatment Strategy in ICBT, and explore outcome prediction further by evaluating the accuracy of an empirically supported classification algorithm, the time point in treatment when acceptable accuracy can be reached, and the accuracy of ICBT-therapists' own predictions. Preliminary benchmarks regarding the clinical usefulness of prediction will be established. Studies:Four studies were performed: Study I was a randomized controlled trial (RCT; n=251) where patients' risk of treatment Failure (Red=high risk of failure, Green=low risk) was predicted during week 4 out of 9 in ICBT for Insomnia. Red patients (n=102) were then randomized to either continuing with standard treatment (n=51) or having their treatment individually adapted (n=51). In Study II, the classification algorithm from Study I was evaluated in terms of classification accuracy and the contribution of the different predictors used. In Study III, data from 4310 regular care ICBT-patients having received treatment for either Depression, Social anxiety disorder or Panic disorder were analyzed in a series of multiple regression models using weekly observations of the primary symptom measure as predictors to classify risk of Failure. As a contrast, Study IV examines ICBT therapists' own predictions on both categorical and continuous treatment outcomes, as they made predictions for each of their patients (n=897) during week 4 in the same three treatments as in Study III. Results:The RCT was successful in that Red patients receiving Adapted treatment improved significantly more than Red patients receiving standard treatment, and their odds of failure were nearly cut in half. Green patients did better than Red patients, indicating that the accuracy of the classification algorithm was clinically useful. Study II showed that the balanced accuracy of the classifier was 67% and that only 11 of 21 predictors correlated significantly with Failure. Notable predictors were symptom levels as well as different markers of treatment engagement. Study III and IV showed that acceptable predictions could be made halfway through treatment using only symptom scores and basic statistics, and that ICBT-...

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This study applied supervised machine learning with multi-modal data to predict remission of major depressive disorder (MDD) after psychotherapy. Genotyped adult patients (n = 894, 65.5% women, age 18–75 years) diagnosed with mild-to-moderate MDD and treated with guided Internet-based Cognitive Behaviour Therapy (ICBT) at the Internet Psychiatry Clinic in Stockholm were included (2008–2016). Predictor types were demographic, clinical, process (e.g., time to complete online questionnaires), and genetic (polygenic risk scores). Outcome was remission status post ICBT (cut-off ≤10 on MADRS-S). Data were split into train (60%) and validation (40%) given ICBT start date. Predictor selection employed human expertise followed by recursive feature elimination. Model derivation was internally validated through cross-validation. The final random forest model was externally validated against a (i) null, (ii) logit, (iii) XGBoost, and (iv) blended meta-ensemble model on the hold-out validation set. Feature selection retained 45 predictors representing all four predictor types. With unseen validation data, the final random forest model proved reasonably accurate at classifying post ICBT remission (Accuracy 0.656 [0.604, 0.705], P vs null model = 0.004; AUC 0.687 [0.631, 0.743]), slightly better vs logit (bootstrap D = 1.730, P = 0.084) but not vs XGBoost (D = 0.463, P = 0.643). Transparency analysis showed model usage of all predictor types at both the group and individual patient level. A new, multi-modal classifier for predicting MDD remission status after ICBT treatment in routine psychiatric care was derived and empirically validated. The multi-modal approach to predicting remission may inform tailored treatment, and deserves further investigation to attain clinical usefulness.

Recent research in wireless communications has achieved important results by exploring more and more sophisticated solutions involving power control. Cross-layer design and topology control are the main examples. Although much has been done in the theoretical domain, there is still a large gap between theory and practice. In this paper, we investigate whether current IEEE 802.11 devices are able to comply with cross-layer and topology control requirements. Our study and associated measurement results reveal that many novel power control solutions cannot be efficiently implemented over existing IEEE 802.11 cards.

This paper outlines the tradeoffs involved in utilizing Information-Centric Networking (ICN) for Internet of Things (IoT) scenarios. It describes contexts and applications where the IoT would benefit from ICN, and where a hostcentric approach would be better. Requirements imposed by the heterogeneous nature of IoT networks are discussed in terms of connectivity, power availability, computational and storage capacity. Design choices are then proposed for an IoT architecture to handle these requirements, while providing efficiency and scalability. An objective is to not require any IoT specific changes of the ICN architecture per se, but we do indicate some potential modifications of ICN that would improve efficiency and scalability for IoT and other applications.

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Large quantities of information are shared through online social networks, making them attractive sources of data for social network research. When studying the usage of online social networks, these data may not describe properly users' behaviours. For instance, the data collected often include content shared by the users only, or content accessible to the researchers, hence obfuscating a large amount of data that would help understanding users' behaviours and privacy concerns. Moreover, the data collection methods employed in experiments may also have an effect on data reliability when participants self-report inacurrate information or are observed while using a simulated application. Understanding the effects of these collection methods on data reliability is paramount for the study of social networks; for understanding user behaviour; for designing socially-aware applications and services; and for mining data collected from such social networks and applications. This chapter reviews previous research which has looked at social network data collection and user behaviour in these networks. We highlight shortcomings in the methods used in these studies, and introduce our own methodology and user study based on the Experience Sampling Method; we claim our methodology leads to the collection of more reliable data by capturing both those data which are shared and not shared. We conclude with suggestions for collecting and mining data from online social networks.