Cryptographic techniques for personal communication systems security

The advent of personal communication systems within the last decade has depended upon the utilization of advanced digital schemes for source and channel coding and for modulation. The inherent digital nature of the communications processing has allowed the convenient incorporation of cryptographic techniques to implement security in these communications systems. There are various security requirements, of both the service provider and the mobile subscriber, which may be provided for in a personal communications system. Such security provisions include the privacy of user data, the authentication of communicating parties, the provision for data integrity, and the provision for both location confidentiality and party anonymity. This thesis is concerned with an investigation of the private-key and public-key cryptographic techniques pertinent to the security requirements of personal communication systems and an analysis of the security provisions of Second-Generation personal communication systems is presented. Particular attention has been paid to the properties of the cryptographic protocols which have been employed in current Second-Generation systems. It has been found that certain security-related protocols implemented in the Second-Generation systems have specific weaknesses. A theoretical evaluation of these protocols has been performed using formal analysis techniques and certain assumptions made during the development of the systems are shown to contribute to the security weaknesses. Various attack scenarios which exploit these protocol weaknesses are presented. The Fiat-Sharmir zero-knowledge cryptosystem is presented as an example of how asymmetric algorithm cryptography may be employed as part of an improved security solution. Various modifications to this cryptosystem have been evaluated and their critical parameters are shown to be capable of being optimized to suit a particular applications. The implementation of such a system using current smart card technology has been evaluated.

Patients’ and health professionals’ views and experiences of atrial fibrillation and oral-anticoagulant therapy:a qualitative meta-synthesis

Objective - Atrial fibrillation (AF) patients are prescribed oral-anticoagulant (OAC) therapy, often warfarin, to reduce stroke risk. We explored existing qualitative evidence about patients’ and health professionals’ experiences of OAC therapy. Methods - Systematic searches of eight bibliographic databases were conducted. Quality was appraised using the Critical Appraisal Skills Programme tool and data from ten studies were synthesised qualitatively. Results - Four third-order constructs, emerged from the final step in the analysis process: (1) diagnosing AF and the communication of information, (2) deciding on OAC therapy, (3) challenges revolving around patient issues, and (4) healthcare challenges. Synthesis uncovered perspectives that could not be achieved through individual studies. Conclusion - Physicians’ and patients’ experiences present a dichotomy of opinion on decision-making, which requires further exploration and changes in practice. Outcomes of workload pressure on both health professionals and patients should be investigated. The need for on-going support and education to patients and physicians is critical to achieve best practice and treatment adherence. Practice implications - Such research could encourage health professionals to understand and attend better to the needs and concerns of the patient. Additionally these findings can be used to inform researchers and healthcare providers in developing educational interventions with both patients and health professionals.

Risk communication and social media:are we ready?

Oral presentation

Talking about depression:an analogue study of physician gender and communication style on patient disclosures

Objectives: To disentangle the effects of physician gender and patient-centered communication style on patients' oral engagement in depression care. Methods: Physician gender, physician race and communication style (high patient-centered (HPC) and low patient-centered (LPC)) were manipulated and presented as videotaped actors within a computer simulated medical visit to assess effects on analogue patient (AP) verbal responsiveness and care ratings. 307 APs (56% female; 70% African American) were randomly assigned to conditions and instructed to verbally respond to depression-related questions and indicate willingness to continue care. Disclosures were coded using Roter Interaction Analysis System (RIAS). Results: Both male and female APs talked more overall and conveyed more psychosocial and emotional talk to HPC gender discordant doctors (all p <.05). APs were more willing to continue treatment with gender-discordant HPC physicians (p <.05). No effects were evident in the LPC condition. Conclusions: Findings highlight a role for physician gender when considering active patient engagement in patient-centered depression care. This pattern suggests that there may be largely under-appreciated and consequential effects associated with patient expectations in regard to physician gender that these differ by patient gender. Practice implications: High patient-centeredness increases active patient engagement in depression care especially in gender discordant dyads. © 2014.

Oral anticoagulation in atrial fibrillation, the patients and physicians experiences of the consultation:a qualitative study

Background: Oral anticoagulation (OAC) reduces stroke risk in patients with atrial fibrillation (AF), however it is still underutilized and sometimes refused by patients. This project was divided in two inter-related studies. Study 1 explored the experiences that influence prescription of OAC by physicians. Study 2 explored the experiences which influence patients' decisions to accept, decline or discontinue OAC. Methods: Semi-structured individual interviews were conducted in both studies. In Study 1four sub-groups of physicians (n = 16) experienced with OAC in AF were interviewed: consultant cardiologists, consultant general physicians, general practitioners and cardiology registrars. In Study 2 three sub-groups of patients (n = 11) diagnosed with AF were interviewed; those who accepted, refused, and who discontinued warfarin. Results: Study 1: Two over-arching themes emerged from doctors' experiences: (1) communicating information and (2) challenges with OAC prescription for AF. Physicians still adopt a paternalistic approach to decision-making. They should instead motivate patients to take part in treatment discussions and choices should reflect the patient's needs and concerns. Physician education should focus more on communication skills, individualised care and time-management as these are critical for patient adherence. Continuous OAC education for AF should adopt a multi-disciplinary approach. Further, interpreters should also be educated on medical communication skills. Study 2: Three over-arching themes comprised patients' experiences: (1) the initial consultation, (2) life after the consultation, and (3) patients' reflections. Patient education during the initial consultation was critical in increasing patient's knowledge of OAC. On-going patient education is imperative to maintain adherence. Patients valued physicians' concern for their needs during decision-making. Patients who had experience of stroke were more receptive to education aimed towards stroke risk reduction rather than bleeding risk. Patients' perceptions of warfarin are also influenced by the media. Comment: Qualitative research is crucial in exploring barriers to treatment as it provides an excellent insight into patients' experiences of healthcare. A patient-centred approach should be adopted and incorporated into physicians' education. Education and patient involvement in the decision-making process is essential to promote treatment acceptance and long-term adherence