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Background: Indirect treatment comparison (ITC) and mixed treatment comparisons (MTC) have been increasingly used in network meta-analyses. This simulation study comprehensively investigated statistical properties and performances of commonly used ITC and MTC methods, including simple ITC (the Bucher method), frequentist and Bayesian MTC methods. Methods: A simple network of three sets of two-arm trials with a closed loop was simulated. Different simulation scenarios were based on different number of trials, assumed treatment effects, extent of heterogeneity, bias and inconsistency. The performance of the ITC and MTC methods was measured by the type I error, statistical power, observed bias and mean squared error (MSE). Results: When there are no biases in primary studies, all ITC and MTC methods investigated are on average unbiased. Depending on the extent and direction of biases in different sets of studies, ITC and MTC methods may be more or less biased than direct treatment comparisons (DTC). Of the methods investigated, the simple ITC method has the largest mean squared error (MSE). The DTC is superior to the ITC in terms of statistical power and MSE. Under the simulated circumstances in which there are no systematic biases and inconsistencies, the performances of MTC methods are generally better than the performance of the corresponding DTC methods. For inconsistency detection in network meta-analysis, the methods evaluated are on average unbiased. The statistical power of commonly used methods for detecting inconsistency is very low. Conclusions: The available methods for indirect and mixed treatment comparisons have different advantages and limitations, depending on whether data analysed satisfies underlying assumptions. To choose the most valid statistical methods for research synthesis, an appropriate assessment of primary studies included in evidence network is required. [ABSTRACT FROM AUTHOR]

Bayesian approaches to inference in cluster randomized trials have been investigated for normally distributed and binary outcome measures. However, relatively little attention has been paid to outcome measures which are counts of events. We discuss an extension of previously published Bayesian hierarchical models to count data, which usually can be assumed to be distributed according to a Poisson distribution. We develop two models, one based on the traditional rate ratio, and one based on the rate difference which may often be more intuitively interpreted for clinical trials, and is needed for economic evaluation of interventions. We examine the relationship between the intracluster correlation coefficient (ICC) and the between-cluster variance for each of these two models. In practice, this allows one to use the previously published evidence on ICCs to derive an informative prior distribution which can then be used to increase the precision of the posterior distribution of the ICC. We demonstrate our models using a previously published trial assessing the effectiveness of an educational intervention and a prior distribution previously derived. We assess the robustness of the posterior distribution for effectiveness to departures from a normal distribution of the random effects. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Thirty-five children’s trust pathfinders, local cross-sector partnerships, were introduced across England in 2003 to promote greater integration in children’s services. Using administrative performance data, this paper tracks yearly trends in child service outputs and child well-being outcomes from 1997 to 2004 in these local areas, including the period before their introduction. Professional perceptions of change in child outcomes are also presented. Time series regression analysis shows there was a general improvement in England in these selected performance indicators prior to the introduction of children’s trusts pathfinders. Children’s trust pathfinder areas initially focusing on ‘all children’ in their local area, rather than selected groups of children, showed the most progress. There was no consistent quantitative evidence for better outcomes in more integrated areas, however, 25 of the 35 survey respondents provided locally specific examples of children’s trust pathfinder arrangements improving outcomes for children and young people. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Task shifting of antiretroviral treatment from doctors to primary-care nurses in South Africa (STRETCH): a pragmatic, parallel, cluster-randomised trial," by Lara Fairall and colleagues in the September 8, 2012 issue.

Background: The development of strategies to better detect and manage patients with multiple long-term conditions requires estimates of the most prevalent condition combinations. However, standard meta-analysis tools are not well suited to synthesising heterogeneous multimorbidity data., Methods: We developed a statistical model to synthesise data on associations between diseases and nationally representative prevalence estimates and applied the model to South Africa. Published and unpublished data were reviewed, and meta-regression analysis was conducted to assess pairwise associations between 10 conditions: arthritis, asthma, chronic obstructive pulmonary disease (COPD), depression, diabetes, HIV, hypertension, ischaemic heart disease (IHD), stroke and tuberculosis. The national prevalence of each condition in individuals aged 15 and older was then independently estimated, and these estimates were integrated with the ORs from the meta-regressions in a statistical model, to estimate the national prevalence of each condition combination., Results: The strongest disease associations in South Africa are between COPD and asthma (OR 14.6, 95% CI 10.3 to 19.9), COPD and IHD (OR 9.2, 95% CI 8.3 to 10.2) and IHD and stroke (OR 7.2, 95% CI 5.9 to 8.4). The most prevalent condition combinations in individuals aged 15+ are hypertension and arthritis (7.6%, 95% CI 5.8% to 9.5%), hypertension and diabetes (7.5%, 95% CI 6.4% to 8.6%) and hypertension and HIV (4.8%, 95% CI 3.3% to 6.6%). The average numbers of comorbidities are greatest in the case of COPD (2.3, 95% CI 2.1 to 2.6), stroke (2.1, 95% CI 1.8 to 2.4) and IHD (1.9, 95% CI 1.6 to 2.2)., Conclusion: South Africa has high levels of HIV, hypertension, diabetes and arthritis, by international standards, and these are reflected in the most prevalent condition combinations. However, less prevalent conditions such as COPD, stroke and IHD contribute disproportionately to the multimorbidity burden, with high rates of comorbidity. This modelling approach can be used in other settings to characterise the most important disease combinations and levels of comorbidity., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Objective: This study aims to study the prognostic impact of left ventricular function on mortality and examine the effect of age on the prognostic value of left ventricular function., Methods: We examined the myocardial ischaemia national audit project registry (2006-2010) data with a mean follow-up of 2.1 years. Left ventricular function was categorised into good (ejection fraction ⩾50%), moderate (ejection fraction 30-49%) and poor (ejection fraction <30%) categories. Cox proportional hazards models were constructed to examine the prognostic significance of left ventricular function in different age groups (<65, 65-74, 75-84 and ⩾85 years) on all-cause mortality adjusting for baseline variables., Results: Out of 424,848 patients, left ventricular function data were available for 123,609. Multiple imputations were used to impute missing values of left ventricular function and the final sample for analyses was drawn from 414,305. After controlling for confounders, 339,887 participants were included in the regression models. For any age group, mortality was higher with a worsening degree of left ventricular impairment. Increased age reduced the adverse prognosis associated with reduced left ventricular function (hazard ratios of death comparing poor left ventricular function to good left ventricular function were 2.11, 95% confidence interval 1.88-2.37 for age <65 years and 1.28, 95% confidence interval 1.20-1.36 for age ⩾85 years). Older patients had a high mortality risk even in those with good left ventricular function. Hazard ratios of mortality for ⩾85 compared to <65 years (hazard ratio = 1.00) within good, moderate and poor ejection fraction groups were 5.89, 4.86 and 3.43, respectively., Conclusions: In patients with acute coronary syndrome, clinicians should interpret the prognostic value of left ventricular function taking into account the patient's age.

Background: South Africa (SA) is facing a heavy burden of non-communicable diseases (NCDs). Few studies address multimorbidity, control and treatment of NCDs in patients attending primary healthcare (PHC) clinics., Objectives: To describe multimorbidity, related risk factors, disease severity and treatment status of patients with four important NCDs attending public sector PHC clinics in two districts in SA., Methods: A cross-sectional sample of patients completed baseline data collection for a randomised controlled trial of a health systems intervention. The study population comprised adults attending PHC clinics in the Eden and Overberg districts of the Western Cape in 2011. Four subgroups of patients were identified: hypertension, diabetes, chronic respiratory disease and depression. A total of 4 393 participants enrolled from 38 clinics completed a baseline structured questionnaire and had measurements taken. Prescription data were recorded., Results: Of participants with hypertension, diabetes, respiratory disease and depression, 80%, 92%, 88% and 80%, respectively, had at least one of the other three conditions. There were low levels of control and treatment: 59% of participants with hypertension had a blood pressure ≥140/90 mmHg, the mean haemoglobin A1c (HbA1c) value in participants with diabetes was 9%, 12% of participants in the depression group were prescribed an antidepressant at a therapeutic dose, and 48% of respiratory participants were prescribed a b2-agonist and 34% an inhaled corticosteroid., Conclusion: Considerable multimorbidity and unmet treatment needs exist among patients with NCDs attending public sector PHC clinics. Improved strategies are required for diagnosing and managing NCDs in this sector.

Background: Integration of HIV care into primary care is a potential strategy to improve access to antiretroviral therapy (ART) in high-burden countries. This study was conducted to determine the effect of integration of HIV care on the survival of patients needing ART., Methods: A questionnaire was used to measure the integration of HIV care into primary care during a randomized controlled trial of task shifting and decentralization of HIV care in South Africa. Cox proportional hazard ratios (HRs) were estimated for the effect of 5 different integration scores (total, pre-ART, ART, mainstreaming HIV, and internal integration) on the survival of patients with CD4 count ≤350 cells per microliter and not yet on ART., Results: A total of 9252 patients were followed up for 12-18 months. Cox proportional HRs adjusted for patient and clinic characteristics showed decreased risk of mortality in clinics with high scores for total integration [HR, 0.97; 95% confidence interval (CI), 0.95 to 0.98; P < 0.001], ART integration (HR, 0.94; 95% CI, 0.90 to 0.99; P = 0.013), and internal integration (HR, 0.97; 95% CI, 0.95 to 1.00; P = 0.041). Analysis of the effect of component scores adjusted for patient characteristics only showed decreased risk of mortality in clinics with high scores for total integration (HR, 0.97; 95% CI, 0.94 to 1.00; P = 0.032), pre-ART integration (HR, 0.92; 95% CI, 0.85 to 0.99; P = 0.027), ART integration (HR, 0.95; 95% CI, 0.93 to 0.98; P = 0.001), and mainstreaming HIV (HR, 0.90; 95% CI, 0.83 to 0.97; P = 0.007)., Conclusion: In a context of task shifting and decentralization of care, integration of HIV care into primary care is associated with improved survival of HIV-positive patients needing ART.

Objective: To investigate whether PALSA PLUS, an on-site educational outreach programme of non-didactic, case based, iterative clinical education of staff, led by a trainer, can increase access to and comprehensiveness of care for patients with HIV/AIDS., Design: Cluster randomised trial., Setting: Public primary care clinics offering HIV/AIDS care, antiretroviral treatment (ART), tuberculosis care, and ambulatory primary care in Free State province, South Africa., Participants: Fifteen clinics all implementing decentralisation and task shifting were randomised. The clinics cared for 400,000 general primary care patients and 10,136 patients in an HIV/AIDS/ART programme. There were 150 nurses., Intervention: On-site outreach education in eight clinics; no such education in seven (control)., Main Outcome Measures: Provision of co-trimoxazole prophylaxis among patients referred to the HIV/AIDS/ART programme, and detection of cases of tuberculosis among those in the programme. Proportion of patients in the programme enrolled through general primary care consultations., Results: Patients referred to the HIV/AIDS programme through general primary care at intervention clinics were more likely than those at control clinics to receive co-trimoxazole prophylaxis (41%, (2253/5523) v 32% (1340/4210); odds ratio 1.95, 95% confidence interval 1.11 to 3.40), and tuberculosis was more likely to be diagnosed among patients with HIV/AIDS/ART (7% (417/5793) v 6% (245/4343); 1.25, 1.01 to 1.55). Enrolment in the HIV/AIDS and ART programme through HIV testing in general primary care was not significantly increased (53% v 50%; 1.19, 0.51 to 2.77). Secondary outcomes were similar, except for weight gain, which was higher in the intervention group (2.3 kg v 1.9 kg, P<0.001)., Conclusion: Though outreach education is an effective and feasible strategy for improving comprehensiveness of care and wellbeing of patients with HIV/AIDS, there is no evidence that it increases access to the ART programme. It is now being widely implemented in South Africa., Trial Registration: Current Controlled Trials ISRCTN 24820584.