An Empirical investigation into metrics for object-oriented software

Object-Oriented methods have increased in popularity over the last decade, and are now the norm for software development in many application areas. Many claims were made for the superiority of object-oriented methods over more traditional methods, and these claims have largely been accepted, or at least not questioned by the software community. Such was the motivation for this thesis. One way of capturing information about software is the use of software metrics. However, if we are to have faith in the information, we must be satisfied that these metrics do indeed tell us what we need to know. This is not easy when the software characteristics we are interested in are intangible and unable to be precisely defined. This thesis considers the attempts to measure software and to make predictions regarding maintainabilty and effort over the last three decades. It examines traditional software metrics and considers their failings in the light of the calls for better standards of validation in terms of measurement theory and empirical study. From this five lessons were derived. The relatively new area of metrics for object-oriented systems is examined to determine whether suggestions for improvement have been widely heeded. The thesis uses an industrial case study and an experiment to examine one feature of objectorientation, inheritance, and its effect on aspects of maintainability, namely number of defects and time to implement a change. The case study is also used to demonstrate that it is possible to obtain early, simple and useful local prediction systems for important attributes such as system size and defects, using readily available measures rather than attempting predefined and possibly time consuming metrics which may suffer from poor definition, invalidity or inability to predict or capture anything of real use. The thesis concludes that there is empirical evidence to suggest a hypothesis linking inheritance and increased incidence of defects and increased maintenance effort and that more empirical studies are needed in order to test the hypothesis. This suggests that we should treat claims regarding the benefits of object-orientation for maintenance with some caution. This thesis also concludes that with the ability to produce, with little effort, accurate local metrics, we have an acceptable substitute for the large predefined metrics suites with their attendant problems

Effect of telecare on use of health and social care services: findings from the Whole Systems Demonstrator cluster randomised trial

Objective: to assess the impact of telecare on the use of social and health care. Part of the evaluation of the Whole Systems Demonstrator trial. Participants and setting: a total of 2,600 people with social care needs were recruited from 217 general practices in three areas in England. Design: a cluster randomised trial comparing telecare with usual care, general practice being the unit of randomisation. Participants were followed up for 12 months and analyses were conducted as intention-to-treat. Data sources: trial data were linked at the person level to administrative data sets on care funded at least in part by local authorities or the National Health Service. Main outcome measures: the proportion of people admitted to hospital within 12 months. Secondary endpoints included mortality, rates of secondary care use (seven different metrics), contacts with general practitioners and practice nurses, proportion of people admitted to permanent residential or nursing care, weeks in domiciliary social care and notional costs. Results: 46.8% of intervention participants were admitted to hospital, compared with 49.2% of controls. Unadjusted differences were not statistically significant (odds ratio: 0.90, 95% CI: 0.75–1.07, P = 0.211). They reached statistical significance after adjusting for baseline covariates, but this was not replicated when adjusting for the predictive risk score. Secondary metrics including impacts on social care use were not statistically significant. Conclusions: telecare as implemented in the Whole Systems Demonstrator trial did not lead to significant reductions in service use, at least in terms of results assessed over 12 months

Effect of telehealth on quality of life and psychological outcomes over 12 months (Whole Systems Demonstrator telehealth questionnaire study): nested study of patient reported outcomes in a pragmatic, cluster randomised controlled trial

Objective:- To assess the effect of second generation, home based telehealth on health related quality of life, anxiety, and depressive symptoms over 12 months in patients with long term conditions. Design:- A study of patient reported outcomes (the Whole Systems Demonstrator telehealth questionnaire study; baseline n=1573) was nested in a pragmatic, cluster randomised trial of telehealth (the Whole Systems Demonstrator telehealth trial, n=3230). General practice was the unit of randomisation, and telehealth was compared with usual care. Data were collected at baseline, four months (short term), and 12 months (long term). Primary intention to treat analyses tested treatment effectiveness; multilevel models controlled for clustering by general practice and a range of covariates. Analyses were conducted for 759 participants who completed questionnaire measures at all three time points (complete case cohort) and 1201 who completed the baseline assessment plus at least one other assessment (available case cohort). Secondary per protocol analyses tested treatment efficacy and included 633 and 1108 participants in the complete case and available case cohorts, respectively. Setting:- Provision of primary and secondary care via general practices, specialist nurses, and hospital clinics in three diverse regions of England (Cornwall, Kent, and Newham), with established integrated health and social care systems. Participants:- Patients with chronic obstructive pulmonary disease (COPD), diabetes, or heart failure recruited between May 2008 and December 2009. Main outcome measures:- Generic, health related quality of life (assessed by physical and mental health component scores of the SF-12, and the EQ-5D), anxiety (assessed by the six item Brief State-Trait Anxiety Inventory), and depressive symptoms (assessed by the 10 item Centre for Epidemiological Studies Depression Scale). Results:- In the intention to treat analyses, differences between treatment groups were small and non-significant for all outcomes in the complete case (0.480≤P≤0.904) or available case (0.181≤P≤0.905) cohorts. The magnitude of differences between trial arms did not reach the trial defined, minimal clinically important difference (0.3 standardised mean difference) for any outcome in either cohort at four or 12 months. Per protocol analyses replicated the primary analyses; the main effect of trial arm (telehealth v usual care) was non-significant for any outcome (complete case cohort 0.273≤P≤0.761; available case cohort 0.145≤P≤0.696). Conclusions:- Second generation, home based telehealth as implemented in the Whole Systems Demonstrator Evaluation was not effective or efficacious compared with usual care only. Telehealth did not improve quality of life or psychological outcomes for patients with chronic obstructive pulmonary disease, diabetes, or heart failure over 12 months. The findings suggest that concerns about potentially deleterious effect of telehealth are unfounded for most patients. Trial Registration: ISRCTN43002091

Cost-effectiveness of telecare for people with social care needs: the Whole Systems Demonstrator cluster randomised trial

Purpose of the study: to examine the costs and cost-effectiveness of ‘second-generation’ telecare, in addition to standard support and care that could include ‘first-generation’ forms of telecare, compared with standard support and care that could include ‘first-generation’ forms of telecare. Design and methods: a pragmatic cluster-randomised controlled trial with nested economic evaluation. A total of 2,600 people with social care needs participated in a trial of community-based telecare in three English local authority areas. In the Whole Systems Demonstrator Telecare Questionnaire Study, 550 participants were randomised to intervention and 639 to control. Participants who were offered the telecare intervention received a package of equipment and monitoring services for 12 months, additional to their standard health and social care services. The control group received usual health and social care. Primary outcome measure: incremental cost per quality-adjusted life year (QALY) gained. The analyses took a health and social care perspective. Results: cost per additional QALY was £297,000. Cost-effectiveness acceptability curves indicated that the probability of costeffectiveness at a willingness-to-pay of £30,000 per QALY gained was only 16%. Sensitivity analyses combining variations in equipment price and support cost parameters yielded a cost-effectiveness ratio of £161,000 per QALY. Implications: while QALY gain in the intervention group was similar to that for controls, social and health services costs were higher. Second-generation telecare did not appear to be a cost-effective addition to usual care, assuming a commonly accepted willingness to pay for QALYs

Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes

The Youth Anxiety Measure for DSM-5 (YAM-5):Development and First Psychometric Evidence of a New Scale for Assessing Anxiety Disorders Symptoms of Children and Adolescents

The Youth Anxiety Measure for DSM-5 (YAM-5) is a new self- and parent-report questionnaire to assess anxiety disorder symptoms in children and adolescents in terms of the contemporary classification system. International panels of childhood anxiety researchers and clinicians were used to construct a scale consisting of two parts: part one consists of 28 items and measures the major anxiety disorders including separation anxiety disorder, selective mutism, social anxiety disorder, panic disorder, and generalized anxiety disorder, whereas part two contains 22 items that focus on specific phobias and (given its overlap with situational phobias) agoraphobia. In general, the face validity of the new scale was good; most of its items were successfully linked to the intended anxiety disorders. Notable exceptions were the selective mutism items, which were frequently considered as symptoms of social anxiety disorder, and some specific phobia items especially of the natural environment, situational and other type, that were regularly assigned to an incorrect category. A preliminary investigation of the YAM-5 in non-clinical (N = 132) and clinically referred (N = 64) children and adolescents indicated that the measure was easy to complete by youngsters. In addition, support was found for the psychometric qualities of the measure: that is, the internal consistency was good for both parts, as well as for most of the subscales, the parent-child agreement appeared satisfactory, and there was also evidence for the validity of the scale. The YAM-5 holds promise as a tool for assessing anxiety disorder symptoms in children and adolescents

Exploring the impact of a Tele-health intervention on specific quality of life domains and psychological well-being in diabetic patients within the Whole Systems Demonstrator Questionnaire Study

INTRODUCTION: Much is written about the promise of Telehealth (TH) and there is great enthusiasm about its potential. However, many studies of TH do not meet orthodox quality standards. Evidence-based on assimilating findings from a few small trials of variable methodological quality presents equivocal findings and makes results difficult to interpret. Robust evidence to inform policy decisions is considered to be lacking (Ekeland et al., 2010). This remains the case when specific long-term conditions such as diabetes are considered with regards to health related quality of life (HRQoL) outcomes. The WSD study aimed to address some of these concerns. AIMS: This study investigated the impact of TH on disease-specific HRQoL, generic HRQoL and psychological outcomes (anxiety and depression) in patients with diabetes, utilising longitudinal questionnaire data from the WSD Telehealth Study. DESIGN: The WSD Telehealth Questionnaire Study is pragmatic cluster-randomised controlled trial evaluating a broad range of patient-reported outcome measures. Participants were recruited from three sites in the UK (Cornwall, Kent and Newham). The current analyses focus on participants with diabetes. METHODS: Over 400 participants with diabetes completed measures of disease-specific HRQoL (DHP), generic HRQoL (UK SF-12; EQ5D), anxiety (Brief STAI) and depression (CESD-10) at baseline. Short- and long-term follow-up assessments were conducted. Multi-level modelling analyses of difference in outcomes between trial arm groups and across time were conducted with appropriate covariates. RESULTS AND CONCLUSIONS: Findings and conclusions from the WSD Telehealth Study are embargoed until these analyses have been peer-reviewed and accepted for publication

The effect of Telehealth on disease-specific quality of life in patients with heart failure: the Whole Systems Demonstrator Telehealth Questionnaire Study

INTRODUCTION: Primary studies and systematic reviews that have examined the effect of Telehealth (TH) on Health-Related Quality of Life (HRQoL) typically conclude that TH leads to quality of life improvements. The evidence base on which such conclusions rest is characterised by methodologically weak studies that generate equivocal findings. The effectiveness of TH, in terms of quality of life benefits, has yet to be substantiated in high-quality trials. AIMS: Using data from the WSD Telehealth Questionnaire Study we assessed the impact of TH on disease-specific HRQoL, generic HRQoL and psychological outcomes (anxiety and depression) in patients with heart failure, over a 12-month period. DESIGN: The WSD Telehealth Questionnaire Study is pragmatic cluster-randomised controlled trial evaluating a broad range of patient-reported outcome measures. Participants were recruited from three Sites in the UK (Cornwall, Kent and Newham). The current analyses focus on participants with heart failure. METHODS: Over 500 participants with heart failure completed measures of disease-specific HRQoL (MLHFQ), generic HRQoL (UK SF-12; EQ5D), anxiety (Brief STAI) and depression (CESD-10) at baseline. Follow-up assessments were conducted at 4 and 12 months. RESULTS: Primary and sensitivity analyses will be presented for the heart failure cohort and interpreted in light of existing WSD findings that examine generic HRQoL in a pooled clinical sample comprising participants with heart failure, COPD and diabetes. Specific findings from the WSD Telehealth Questionnaire Study are embargoed until these analyses have been peer-reviewed and accepted for publication. CONCLUSIONS: Conclusions cannot be released until the analyses have been peer-reviewed and accepted for publication

A pragmatic cluster randomised controlled trial of telehealth on disease specific quality of life in patients’ with chronic obstructive pulmonary disease and their health-related quality of life and psychological distress over 1 year in the Whole System

Para Camus, el Arte es una necesidad vital surgida de «una fuente única que alimenta, toda su vida, lo que es y lo que dice», nacida de impulsos del alma canalizados que dan sustento a sus obras y le permiten conocer y conocerse. La creación es, a su juicio, un largo camino para reencontrar, por los desvíos del arte, «las dos o tres imágenes simples y grandes a las que por primera vez se abrió el corazón», un ejercicio necesario para «construir la obra soñada».El primer hombre puede considerarse el esbozo de ese sueño, perfilado en la totalidad de sus creaciones y en la evolución de su planteo ético, estructurado sobre la base de conceptos de felicidad, verdad y justicia, asociados a los de libertad y solidaridad. Es nuestra intención señalar las prefiguraciones de ese proyecto en las reflexiones y los escritos anteriores del autor

The impact on carers of individuals with social care needs: the Whole Systems Demonstrator study

INTRODUCTION: Carers of individuals with social care needs (including frail elderly people, those at risk of falls and those requiring night sitting), are subject to high levels of carer burden, social isolation and poor psychological outcomes. Carers’ worries and concerns include leaving the individual alone; risks of harm to the care-recipient; or household emergencies in their absence. At present there is a lack of research on the impact of telecare interventions on carer outcomes. It is feasible that carers’ anxieties and level of strain may be ameliorated with concomitant increases in quality of life, with the introduction of telecare systems for their care-recipient. OBJECTIVES: This study investigates the secondary impact of telecare on carers, specifically whether the use of telecare reduces informal carer burden and social isolation and whether it improves carers’ psychological well-being and confidence in leaving the care-recipient alone. DESIGN: We report on the prospective analysis of a pragmatic controlled trial on carers of telecare users and controls within the WSD evaluation of telecare (a pragmatic cluster randomised controlled trial investigating the effectiveness of telecare for social care recipients). METHODS: Carers of individuals with social care needs were identified and recruited to the study via a combination of snowball sampling, light touch visits (to users) and self selection. Over 200 carers completed a questionnaire pack at baseline, and at short and long-term follow-ups; with roughly equal numbers of carers of recipients of telecare and recipients of usual care. The questionnaire pack included measures of quality of life (ICECAP), health related quality of life (SF12, EQ5D), psychosocial well-being (STAI-6, CESD10) and care-giver strain measures (CGSI, Carer confidence and anxiety). RESULTS AND CONCLUSIONS: Multi-level modelling of difference in outcomes between carer groups and across time was conducted with appropriate covariates. Specific findings from the Telecare Carers Study are embargoed until these analyses have been peer-reviewed and accepted for publication