Peter W. F. Smith

Volume 54 - Article 9 | Pages 263–308

In this chapter, we present a unique set of harmonized migration estimates for migration within, into and out of the system of 32 European countries (EU). These estimates are available by origin, destination, age, sex and region of birth, for the 2009-19 period and include a statistical assessment of uncertainty. We start by presenting a short background on past efforts to harmonize migration estimates in Europe and then describe the successive steps of the estimation process, from gathering the required information and meta-information on data collection to estimating the ‘true’ migration flows with their measures of uncertainty by using a Bayesian hierarchical model. We conclude by presenting and discussing the results for selected migration flows.

Background: Antimicrobial resistance is a global health threat. Antibiotics are commonly prescribed for children with uncomplicated lower respiratory tract infections, but there is little randomised evidence to support the effectiveness of antibiotics in treating these infections, either overall or relating to key clinical subgroups in which antibiotic prescribing is common (chest signs; fever; physician rating of unwell; sputum/rattly chest; shortness of breath).Objectives: To estimate the clinical effectiveness and cost-effectiveness of amoxicillin for uncomplicated lower respiratory tract infections in children both overall and in clinical subgroups.Design: Placebo-controlled trial with qualitative, observational and cost-effectiveness studies.Setting: UK general practices.Participants: Children aged 1-12 years with acute uncomplicated lower respiratory tract infections.Outcomes: The primary outcome was the duration in days of symptoms rated moderately bad or worse (measured using a validated diary). Secondary outcomes were symptom severity on days 2-4 (0 = no problem to 6 = as bad as it could be); symptom duration until very little/no problem; reconsultations for new or worsening symptoms; complications; side effects; and resource use.Methods: Children were randomised to receive 50 mg/kg/day of oral amoxicillin in divided doses for 7 days, or placebo using pre-prepared packs, using computer-generated random numbers by an independent statistician. Children who were not randomised could participate in a parallel observational study. Semistructured telephone interviews explored the views of 16 parents and 14 clinicians, and the data were analysed using thematic analysis. Throat swabs were analysed using multiplex polymerase chain reaction.Results: A total of 432 children were randomised (antibiotics, n = 221; placebo, n = 211). The primary analysis imputed missing data for 115 children. The duration of moderately bad symptoms was similar in the antibiotic and placebo groups overall (median of 5 and 6 days, respectively; hazard ratio 1.13, 95% confidence interval 0.90 to 1.42), with similar results for subgroups, and when including antibiotic prescription data from the 326 children in the observational study. Reconsultations for new or worsening symptoms (29.7% and 38.2%, respectively; risk ratio 0.80, 95% confidence interval 0.58 to 1.05), illness progression requiring hospital assessment or admission (2.4% vs. 2.0%) and side effects (38% vs. 34%) were similar in the two groups. Complete-case (n = 317) and per-protocol (n = 185) analyses were similar, and the presence of bacteria did not mediate antibiotic effectiveness. NHS costs per child were slightly higher (antibiotics, & POUND;29; placebo, & POUND;26), with no difference in non-NHS costs (antibiotics, & POUND;33; placebo, & POUND;33). A model predicting complications (with seven variables: baseline severity, difference in respiratory rate from normal for age, duration of prior illness, oxygen saturation, sputum/rattly chest, passing urine less often, and diarrhoea) had good discrimination (bootstrapped area under the receiver operator curve 0.83) and calibration. Parents found it difficult to interpret symptoms and signs, used the sounds of the child's cough to judge the severity of illness, and commonly consulted to receive a clinical examination and reassurance. Parents acknowledged that antibiotics should be used only when 'necessary', and clinicians noted a reduction in parents' expectations for antibiotics. Limitations: The study was underpowered to detect small benefits in key subgroups.Conclusion: Amoxicillin for uncomplicated lower respiratory tract infections in children is unlikely to be clinically effective or to reduce health or societal costs. Parents need better access to information, as well as clear communication about the self-management of their child's illness and safety-netting.

Background: Digital interventions offer a potentially cost-effective means to support patient self-management in primary care, but evidence for the feasibility, acceptability and cost-effectiveness of digital interventions remains mixed. This programme focused on the potential for self-management digital interventions to improve outcomes in two common, contrasting conditions (i.e. hypertension and asthma) for which care is currently suboptimal, leading to excess deaths, illness, disability and costs for the NHS. Objectives: The overall purpose was to address the question of how digital interventions can best provide cost-effective support for patient self-management in primary care. Our aims were to develop and trial digital interventions to support patient self-management of hypertension and asthma. Through the process of planning, developing and evaluating these interventions, we also aimed to generate a better understanding of what features and methods for implementing digital interventions could make digital interventions acceptable, feasible, effective and cost-effective to integrate into primary care. Design: For the hypertension strand, we carried out systematic reviews of quantitative and qualitative evidence, intervention planning, development and optimisation, and an unmasked randomised controlled trial comparing digital intervention with usual care, with a health economic analysis and nested process evaluation. For the asthma strand, we carried out a systematic review of quantitative evidence, intervention planning, development and optimisation, and a feasibility randomised controlled trial comparing digital intervention with usual care, with nested process evaluation. Setting: General practices (hypertension, n = 76; asthma, n = 7) across Wessex and Thames Valley regions in Southern England. Participants: For the hypertension strand, people with uncontrolled hypertension taking one, two or three antihypertensive medications. For the asthma strand, adults with asthma and impaired asthma-related quality of life. Interventions: Our hypertension intervention (i.e. HOME BP) was a digital intervention that included motivational training for patients to self-monitor blood pressure, as well as health-care professionals to support self-management; a digital interface to send monthly readings to the health-care professional and to prompt planned medication changes when patients’ readings exceeded recommended targets for 2 consecutive months; and support for optional patient healthy behaviour change (e.g. healthy diet/weight loss, increased physical activity and reduced alcohol and salt consumption). The control group were provided with a Blood Pressure UK (London, UK) leaflet for hypertension and received routine hypertension care. Our asthma intervention (i.e. My Breathing Matters) was a digital intervention to improve the functional quality of life of primary care patients with asthma by supporting illness self-management. Motivational content intended to facilitate use of pharmacological self-management strategies (e.g. medication adherence and appropriate health-care service use) and non-pharmacological self-management strategies (e.g. breathing retraining, stress reduction and healthy behaviour change). The control group were given an Asthma UK (London, UK) information booklet on asthma self-management and received routine asthma care. Main outcome measures: The primary outcome for the hypertension randomised controlled trial was difference between intervention and usual-care groups in mean systolic blood pressure (mmHg) at 12 months, adjusted for baseline blood pressure, blood pressure target (i.e. standard, diabetic or aged > 80 years), age and general practice. The primary outcome for the asthma feasibility study was the feasibility of the trial design, including recruitment, adherence, intervention engagement and retention at follow-up. Health-care utilisation data were collected via notes review. Review methods: The quantitative reviews included a meta-analysis. The qualitative review comprised a meta-ethnography. Results: A total of 622 hypertensive patients were recruited to the randomised controlled trial, and 552 (89%) were followed up at 12 months. Systolic blood pressure was significantly lower in the intervention group at 12 months, with a difference of –3.4 mmHg (95% confidence interval –6.1 to –0.8 mmHg), and this gave an incremental cost per unit of systolic blood pressure reduction of £11 (95% confidence interval £5 to £29). Owing to a cost difference of £402 and a quality-adjusted life-year (QALY) difference of 0.044, long-term modelling puts the incremental cost per QALY at just over £9000. The probability of being cost-effective was 66% at willingness to pay £20,000 per quality-adjusted life-year, and this was higher at higher thresholds. A total of 88 patients were recruited to the asthma feasibility trial (target n = 80; n = 44 in each arm). At 3-month follow-up, two patients withdrew and six patients did not complete outcome measures. At 12 months, two patients withdrew and four patients did not complete outcome measures. A total of 36 out of 44 patients in the intervention group engaged with My Breathing Matters [with a median of four (range 0–25) logins]. Limitations: Although the interventions were designed to be as accessible as was feasible, most trial participants were white and participants of lower socioeconomic status were less likely to take part and complete follow-up measures. Challenges remain in terms of integrating digital interventions with clinical records. Conclusions: A digital intervention using self-monitored blood pressure to inform medication titration led to significantly lower blood pressure in participants than usual care. The observed reduction in blood pressure would be expected to lead to a reduction of 10–15% in patients suffering a stroke. The feasibility trial of My Breathing Matters suggests that a fully powered randomised controlled trial of the intervention is warranted. The theory-, evidence- and person-based approaches to intervention development refined through this programme enabled us to identify and address important contextual barriers to and facilitators of engagement with the interventions. Future work: This research justifies consideration of further implementation of the hypertension intervention, a fully powered randomised controlled trial of the asthma intervention and wide dissemination of our methods for intervention development. Our interventions can also be adapted for a range of other health conditions. Trial and study registration: The trials are registered as ISRCTN13790648 (hypertension) and ISRCTN15698435 (asthma). The studies are registered as PROSPERO CRD42013004773 (hypertension review) and PROSPERO CRD42014013455 (asthma review). Funding: This project was funded by the National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 10, No. 11. See the NIHR Journals Library website for further information.

Background: Approximately 57 million physician appointments annually in the United Kingdom are for minor ailments. These illnesses could be self-cared for, which would potentially lower patients’ anxiety, increase their confidence, and be more convenient. In a randomized controlled trial of the Internet Dr digital intervention, patients with access to the intervention had fewer consultations for respiratory tract infections (RTIs). Having established intervention efficacy, further examination of trial data is required to understand how the intervention works. Objective: This paper reports a process evaluation of Internet Dr usage by the intervention group. The evaluation aims to demonstrate how meaningful usage metrics (ie, interactions that are specific and relevant to the intervention) can be derived from the theoretical principles underlying the intervention, then applied to examine whether these interactions are effective in supporting self-care for RTIs, for whom, and at what time. Methods: The Internet Dr trial recorded patients’ characteristics and usage data over 24 weeks. At follow-up, users reported whether their levels of enablement to cope with their illness changed over the trial period. The Medical Research Council process evaluation guidance and checklists from the framework for Analyzing and Measuring Usage and Engagement Data were applied to structure research questions examining associations between usage and enablement. Results: Viewing pages containing advice on caring for RTIs were identified as a meaningful metric for measuring intervention usage. Almost half of the users (616/1491, 42.31%) viewed at least one advice page, with most people (478/616, 77.6%) accessing them when they initially enrolled in the study. Users who viewed an advice page reported increased enablement to cope with their illness as a result of having participated in the study compared with users who did not (mean 2.12, SD 2.92 vs mean 1.65, SD 3.10; mean difference 0.469, 95% CI 0.082-0.856). The target population was users who had visited their general practitioners for an RTI in the year before the trial, and analyses revealed that this group was more likely to access advice pages (odds ratio 1.35, 95% CI 1.159-1.571; P<.001). Conclusions: The process evaluation identifies viewing advice pages as associated with increased enablement to self-care, even when accessed in the absence of a RTI, meaning that dissemination activities need not be restricted to targeting users who are ill. The intervention was effective at reaching the target population of users who had previously consulted their general practitioners. However, attrition before reaching advice pages was high, highlighting the necessity of prioritizing access during the design phase. These findings provide guidance on how the intervention may be improved and disseminated and have wider implications for minor ailment interventions.

Background: Washing hands helps prevent transmission of seasonal and pandemic respiratory viruses. In a randomized controlled trial (RCT) during the swine flu outbreak, participants with access to a fully automated, digital intervention promoting handwashing reported washing their hands more often and experienced fewer respiratory tract infections than those without access to the intervention. Based on these findings, the intervention was adapted, renamed as “Germ Defence,” and a study was designed to assess the preliminary dissemination of the intervention to the general public to help prevent the spread of seasonal colds and flu. Objective: This study compares the process evaluations of the RCT and Germ Defence dissemination to examine (1) how web-based research enrollment procedures affected those who used the intervention, (2) intervention usage in the 2 contexts, and (3) whether increased intentions to wash hands are replicated once disseminated. Methods: The RCT ran between 2010 and 2012 recruiting participants offline from general practices, with restricted access to the intervention (N=9155). Germ Defence was disseminated as an open access website for use by the general public from 2016 to 2019 (N=624). The process evaluation plan was developed using Medical Research Council guidance and the framework for Analyzing and Measuring Usage and Engagement Data. Both interventions contained a goal-setting section where users self-reported current and intended handwashing behavior across 7 situations. Results: During web-based enrolment, 54.3% (17,511/32,250) of the RCT participants dropped out of the study compared to 36.5% (358/982) of Germ Defence users. Having reached the start of the intervention, 93.8% (8586/9155) of RCT users completed the core section, whereas 65.1% (406/624) of Germ Defence users reached the same point. Users across both studies selected to increase their handwashing in 5 out of 7 situations, including before eating snacks (RCT mean difference 1.040, 95% CI 1.016-1.063; Germ Defence mean difference 0.949, 95% CI 0.766-1.132) and after blowing their nose, sneezing, or coughing (RCT mean difference 0.995, 95% CI 0.972-1.019; Germ Defence mean difference 0.842, 95% CI 0.675-1.008). Conclusions: By comparing the preliminary dissemination of Germ Defence to the RCT, we were able to examine the potential effects of the research procedures on uptake and attrition such as the sizeable dropout during the RCT enrolment procedure that may have led to a more motivated sample. The Germ Defence study highlighted the points of attrition within the intervention. Despite sample bias in the trial context, the intervention replicated increases in intentions to handwash when used “in the wild.” This preliminary dissemination study informed the adaptation of the intervention for the COVID-19 health emergency, and it has now been disseminated globally. Trial Registration: ISRCTN Registry ISRCTN75058295; https://www.isrctn.com/ISRCTN75058295

Estimation of the unknown population size using capture-recapture techniques relies on the key assumption that the capture probabilities are homogeneous across individuals in the population. This is usually accomplished via post-stratification by some key covariates believed to influence individual catchability. Another issue that arises in population estimation from data collected from multiple sources is list dependence, where an individual’s catchability on one list is related to that of another list. The earlier models for population estimation heavily relied upon list independence. However, there are methods available that can adjust the population estimates to account for dependence among lists. In this article, we propose the use of latent class analysis through log-linear modelling to estimate the population size in the presence of both heterogeneity and list dependence. The proposed approach is illustrated using data from the 1988 US census dress rehearsal.