Maximum likelihood continuity mapping for fraud detection

The author describes a novel time-series analysis technique called maximum likelihood continuity mapping (MALCOM), and focuses on one application of MALCOM: detecting fraud in medical insurance claims. Given a training data set composed of typical sequences, MALCOM creates a stochastic model of sequence generation, called a continuity map (CM). A CM maximizes the probability of sequences in the training set given the model constraints, CMs can be used to estimate the likelihood of sequences not found in the training set, enabling anomaly detection and sequence prediction--important aspects of data mining. Since MALCOM can be used on sequences of categorical data (e.g., sequences of words) as well as real valued data, MALCOM is also a potential replacement for database search tools such as N-gram analysis. In a recent experiment, MALCOM was used to evaluate the likelihood of patient medical histories, where ``medical history`` is used to mean the sequence of medical procedures performed on a patient. Physicians whose patients had anomalous medical histories (according to MALCOM) were evaluated for fraud by an independent agency. Of the small sample (12 physicians) that has been evaluated, 92% have been determined fraudulent or abusive. Despite the small sample, these results are encouraging

An articulatorily constrained, maximum entropy approach to speech recognition and speech coding

Hidden Markov models (HMM`s) are among the most popular tools for performing computer speech recognition. One of the primary reasons that HMM`s typically outperform other speech recognition techniques is that the parameters used for recognition are determined by the data, not by preconceived notions of what the parameters should be. This makes HMM`s better able to deal with intra- and inter-speaker variability despite the limited knowledge of how speech signals vary and despite the often limited ability to correctly formulate rules describing variability and invariance in speech. In fact, it is often the case that when HMM parameter values are constrained using the limited knowledge of speech, recognition performance decreases. However, the structure of an HMM has little in common with the mechanisms underlying speech production. Here, the author argues that by using probabilistic models that more accurately embody the process of speech production, he can create models that have all the advantages of HMM`s, but that should more accurately capture the statistical properties of real speech samples--presumably leading to more accurate speech recognition. The model he will discuss uses the fact that speech articulators move smoothly and continuously. Before discussing how to use articulatory constraints, he will give a brief description of HMM`s. This will allow him to highlight the similarities and differences between HMM`s and the proposed technique

A maximum likelihood approach to estimating articulator positions from speech acoustics

This proposal presents an algorithm called maximum likelihood continuity mapping (MALCOM) which recovers the positions of the tongue, jaw, lips, and other speech articulators from measurements of the sound-pressure waveform of speech. MALCOM differs from other techniques for recovering articulator positions from speech in three critical respects: it does not require training on measured or modeled articulator positions, it does not rely on any particular model of sound propagation through the vocal tract, and it recovers a mapping from acoustics to articulator positions that is linearly, not topographically, related to the actual mapping from acoustics to articulation. The approach categorizes short-time windows of speech into a finite number of sound types, and assumes the probability of using any articulator position to produce a given sound type can be described by a parameterized probability density function. MALCOM then uses maximum likelihood estimation techniques to: (1) find the most likely smooth articulator path given a speech sample and a set of distribution functions (one distribution function for each sound type), and (2) change the parameters of the distribution functions to better account for the data. Using this technique improves the accuracy of articulator position estimates compared to continuity mapping -- the only other technique that learns the relationship between acoustics and articulation solely from acoustics. The technique has potential application to computer speech recognition, speech synthesis and coding, teaching the hearing impaired to speak, improving foreign language instruction, and teaching dyslexics to read. 34 refs., 7 figs

Gastrostomy uptake in motor neurone disease: a mixed-methods study of patients’ decision making

Objectives: Gastrostomy decision making is a complicated, multifaceted process for people with motor neuron disease (MND). This study explored demographic and disease-related factors that may impact on gastrostomy uptake; and reasons why people with MND accepted or declined gastrostomy, with a focus on how perceptions of swallowing and nutrition may influence decision making.Design: Prospective, cross sectional, mixed methods.Setting: An Australian multidisciplinary, specialty MND Service.Participants: 33 patients were recommended gastrostomy by the treating medical specialist. 16 of 33 were invited to participate in the prospective decision making study; of whom 10 provided informed consent.Primary and secondary outcome measures: Demographic and disease-related factors contributing to uptake are described. A stepped approach was applied to gain a comprehensive understanding of why people with MND accept or decline gastrostomy. Instruments included standardised assessments, nutrition survey and semistructured interview. Data were collected at three separate appointments, spanning a 3-week period.Results: Gastrostomy uptake was 73% following medical specialist recommendation. Participants took days, weeks or months to consider their preferences, with lengthy hospital waiting times for the procedure. Gender, site of onset and rate of disease progression were observed to contribute to uptake. Age and symptom duration did not. Integration of quantitative and qualitative data suggests that patient perceptions of swallowing and nutrition contribute to gastrostomy acceptance; however, the decision making process is heterogeneous and these factors may not be the sole or primary reasons for acceptance. Other reported factors included: reducing carer burden, improving quality of life, increasing independence, continuing participation in social outings and gaining control.Conclusions: Future research may give greater insight into how healthcare organisations can better facilitate gastrostomy decision making, to meet the needs of people living with MND. Larger, prospective, multisite studies may build on these findings to better inform clinical guidelines and minimise the impacts of delayed gastrostomy insertion

Relational autonomy in breast diseases care: A qualitative study of contextual and social conditions of patients' capacity for decision-making 17 Psychology and Cognitive Sciences 1701 Psychology

Background: A relational approach to autonomy refers to the way in which social conditions and relationships shape a person's self-identity and capacity in decision-making. This article provides an empirical account of how treatment choices for women undergoing breast diseases care are fostered within the dynamics of their relationships with clinicians, family members, and other aspects of their social environment. Methods: This qualitative study recruited ten women undergoing treatment at a breast programme, and eight clinicians supporting their care, in a private teaching hospital in New South Wales, Australia. Fourteen patient-clinician consultation observations and 17 semi-structured interviews were conducted. Schema analysis of interview transcripts were undertaken by a team of researchers and corroborated by observational fieldnotes. Results: Relational identities of patients influenced the rationale for treatment decision-making. Patients drew on supportive resources from family and medical advice from clinicians to progress with treatment goals. While clinicians held much social power over patients as the medical experts, patients highlighted the need for clinicians to earn their trust through demonstrated professionalism. Information exchange created a communicative space for clinicians and patients to negotiate shared values, promoting greater patient ownership of treatment decisions. As treatment progressed, patients' personal experiences of illness and treatment became a source of self-reflection, with a transformative impact on self-confidence and assertiveness. Conclusion: Patients' confidence and self-trust can be fostered by opportunities for communicative engagement and self-reflection over the course of treatment in breast disease, and better integration of their self-identity and social values in treatment decisions

Development and application of an indicator assessment tool for measuring health services accreditation programs

© 2015 Mumford et al. Background: Hospital accreditation programs are internationally widespread and consume increasingly scarce health resources. However, we lack tools to consistently identify suitable indicators to assess and monitor accreditation outcomes. We describe the development and validation of such a tool. Results: Using Australian accreditation standards as our reference point we: reviewed the research evidence for potential indicators; looked for links with existing external indicators; and assessed relevant state and federal policies. We allocated provisional scores, on a five point Likert scale, to the five accountability criteria in the tool: research; accuracy; proximity; no adverse effects; and specificity. An expert panel validated the use of the purpose designed indicator assessment tool. The panel identified hand hygiene compliance rates as a suitable process indicator, and hospital acquired Staphylococcus aureus infection (SAB) rates as an outcome indicator, with the hypothesis that improved hand hygiene compliance rates and lower SAB rates would correlate with accreditation performance. Conclusions: This new tool can be used to identify, analyse, and compare accreditation indicators. Using infection control indicators such as hand hygiene compliance and SAB rates to measure accreditation effectiveness has merit, and their efficacy can be determined by comparing accreditation scores with indicator outcomes. To verify the tool as a robust instrument, testing is needed in other health service domains, both in Australia and internationally. This tool provides health policy makers with an important means for assessing the accreditation programs which form a critical part of the national patient safety and quality framework

Older, vulnerable patient view: a pilot and feasibility study of the patient measure of safety (PMOS) with patients in Australia

Objectives The UK-developed patient measure of safety (PMOS) is a validated tool which captures patient perceptions of safety in hospitals. We aimed (1) to investigate the extent to which the PMOS is appropriate for use with stroke, acute myocardial infarction (AMI) and hip fracture patients in Australian hospitals and (2) to pilot the PMOS for use in a large-scale, national study ‘Deepening our Understanding of Quality in Australia’ (DUQuA). Participants Stroke, AMI and hip fracture patients (n=34) receiving care in 3 wards in 1 large hospital. Methods 2 phases were conducted. First, a ‘think aloud’ study was used to determine the validity of PMOS with this population in an international setting, and to make amendments based on patient feedback. The second phase tested the revised measure to establish the internal consistency reliability of the revised subscales, and piloted the recruitment and administration processes to ensure feasibility of the PMOS for use in DUQuA. Results Of the 43 questions in the PMOS, 13 (30%) were amended based on issues patients highlighted for improvement in phase 1. In phase 2, a total of 34 patients were approached and 29 included, with a mean age of 71.3 years (SD=16.39). Internal consistency reliability was established using interitem correlation and Cronbach's α for all but 1 subscale. The most and least favourably rated aspects of safety differed between the 3 wards. A study log was categorised into 10 key feasibility factors, including liaising with wards to understand operational procedures and identify patterns of patient discharge. Conclusions Capturing patient perceptions of care is crucial in improving patient safety. The revised PMOS is appropriate for use with vulnerable older adult groups. The findings from this study have informed key decisions made for the deployment of this measure as part of the DUQuA study

Disentangling quality and safety indicator data: a longitudinal, comparative study of hand hygiene compliance and accreditation outcomes in 96 Australian hospitals.

The study aims are twofold. First, to investigate the suitability of hand hygiene as an indicator of accreditation outcomes and, second, to test the hypothesis that hospitals with better accreditation outcomes achieve higher hand hygiene compliance rates