Applying coupon-collecting theory to computer-aided assessments

Computer-based tests with randomly generated questions allow a large number of different tests to be generated. Given a fixed number of alternatives for each question, the number of tests that need to be generated before all possible questions have appeared is surprisingly low.Comment: 19 pages; bibliographic information added as follows. To appear in Bingham, N. H., and Goldie, C. M. (eds), Probability and Mathematical Genetics: Papers in Honour of Sir John Kingman. London Math. Soc. Lecture Note Series. Cambridge: Cambridge Univ. Pres

Evaluating interventions for violence prevention using linked MoJ-DfE data: a feasibility study.

ObjectiveTo assess the feasibility of using linked education and offending data (from the National Pupil Database, Department for Education and the Police National Computer, Ministry of Justice) to identify matched control groups to evaluate violence prevention interventions.ApproachWe simulated a plausible intervention (multi-systemic therapy aimed at high-risk young people living in high-risk areas) aimed at reducing the rate of serious violent offending between the ages of 15 and 18 years. We separately simulated an intervention in London and one outside London. We selected eligible individuals aged 14 years for inclusion in the intervention group, modelled the predictors of serious violent offending. then used two different matching algorithms – prognostic score matching and (coarsened) exact matching – to identify matched controls. We compared their effectiveness by measuring the observed rates of serious violence in the two groups.ResultsThe dataset we used dataset included just under 1.5 million individuals born between 1st September 1995 and 31st August 1998 with complete data. Consistent with previous research, factors associated with the risk of serious violence included deprivation, geographical region, sex, ethnicity, attainment, school absence and exclusion, being in care of the local authority or classified as in need, as well as prior offending and some school-level factors. Exact matching or coarsened exact matching was more successful than prognostic score matching at selecting suitable control groups, both within and outside London. Within London, exact matching on sex, ethnicity and any offending before age 14 gave a suitable control group; outside London it was necessary to match on a few additional characteristics in order to obtain well-balanced groups.ConclusionThe linked dataset can feasibly be used to generate suitable matched control groups to evaluate violence prevention interventions; exact matching on key characteristics is potentially the optimal solution. Its utility in practice will depend on regular data updates and having an efficient mechanism for accessing the data for such purposes

Defining adolescent common mental disorders using electronic primary care data: a comparison with outcomes measured using the CIS-R

OBJECTIVE: To compare the prevalence of common mental disorders (CMDs) derived from data held in primary care records with that measured using the revised Clinical Interview Schedule (CIS-R) in order to assess the potential robustness of findings based only on routinely collected data. DESIGN AND SETTING: Comparison study using linkage between the Avon Longitudinal Study of Parents and Children (ALSPAC) and electronic primary care records. PARTICIPANTS: We studied 1562 adolescents who had completed the CIS-R in ALSPAC at age 17–18 years and had linkage established to their primary care records. OUTCOME MEASURES: Outcome measures from ALSPAC were whether or not an individual met International Classification of Diseases-10 criteria for a diagnosis of (1) a CMD or, specifically, (2) depression. Lists of Read codes corresponding to diagnoses, symptoms and treatments were used to create 12 definitions of CMD and depression alone using the primary care data. We calculated sensitivities and specificities of these, using CIS-R definitions as the reference standard. RESULTS: Sensitivities ranged from 5.2% to 24.3% for depression and from 3.8% to 19.2% for CMD. The specificities of all definitions were above 98% for depression and above 96% for CMD. For both outcomes, the definition that included current diagnosis, treatment or symptoms identified the highest proportion of CIS-R cases. CONCLUSIONS: Most individuals meeting case definitions for CMD based on primary care data also met CIS-R case definitions. Conversely many individuals identified as cases using the CIS-R had no evidence of CMD in their clinical records. This suggests that clinical databases are likely to yield underestimates of the burden of CMD in the population. However, clinical records appear to yield valid diagnoses which may be useful for studying risk factors and consequences of CMD. The greatest epidemiological value may be obtained when information is available from survey and clinical records

Risk of death during and after opiate substitution treatment in primary care: prospective observational study in UK General Practice Research Database

Objective To investigate the effect of opiate substitution treatment at the beginning and end of treatment and according to duration of treatment

Using Linkage to Electronic Primary Care Records to Evaluate Recruitment and Nonresponse Bias in The Avon Longitudinal Study of Parents and Children

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Health and Well-Being in Surviving Congenital Heart Disease Patients: An Umbrella Review With Synthesis of Best Evidence

BACKGROUND: Advances in the management of congenital heart disease (CHD) patients have enabled improvement in long-term survival even for those with serious defects. Research priorities (for patients, families and clinicians) have shifted from a focus on how to improve survival to exploring long-term outcomes in patients with CHD. A comprehensive appraisal of available evidence could inform best practice to maximize health and well-being, and identify research gaps to direct further research toward patient and clinical need. We aimed to critically appraise all available published systematic reviews of health and well-being outcomes in adult patients with CHD. METHODS: We conducted an umbrella review, including any systematic reviews that assessed the association of having vs. not having CHD with any long-term health (physical or mental), social (e.g., education, occupation) or well-being [e.g., quality of life (QoL)] outcome in adulthood (≥18-years). RESULTS: Out of 1330 articles screened, we identified five systematic reviews of associations of CHD with adult outcomes. All but one (which studied QoL) explored health outcomes: one cardiovascular, two mental, and one mortality after transplant. CHD patients had a higher risk of stroke, coronary heart disease and heart failure, with the pooled relative risk (RR) for any outcome of 3.12 (95% CI: 3.01 to 3.24), with substantial heterogeneity (I(2) = 99%) explained by the outcome being studied (stronger association for heart failure) and geography (stronger in Europe compared with other regions). CHD patients had a higher risk of anxiety (OR = 2.58 (1.45 to 4.59)], and higher mean scores for depression/anxiety symptoms (difference in means = −0.11 SD (–0.28 to 0.06), I(2) = 94%)]. Compared with patients having a cardiac transplant for other (non-CHD) diseases, CHD patients had higher short-term mortality (RR at 30-days post-transplant = 2.18 [1.62 to 2.93)], with moderate heterogeneity (I(2) = 41%) explained by previous surgery (higher mortality with prior Fontan/Glenn operation). All domains of QoL were lower in patients with Fontan’s circulation than non-CHD adults. CONCLUSION: Adults with CHD have poorer cardiovascular, mental health and QoL outcomes, and higher short-term mortality after transplant. The paucity of systematic reviews, in particular for outcomes such as education, occupation and lifestyles, highlights the need for this to be made a priority by funders and researchers. SYSTEMATIC REVIEW REGISTRATION: [www.crd.york.ac.uk/prospero], identifier [CRD42020175034]