-
[show abstract]
[hide abstract]
ABSTRACT: AIMS: World-wide, more than 30 million people move through prisons annually. Record linkage studies have identified an increased risk of death in ex-prisoners. In order to inform preventive interventions it is necessary to understand who is most at risk, when and why. Limitations of existing studies have rendered synthesis and interpretation of this literature difficult. The aim of this study was to describe methodological characteristics of existing studies and make recommendations for the design, analysis and reporting of future studies. METHODS: Systematic review of studies using record linkage to explore mortality in ex-prisoners. Based on analysis of these studies we illustrate how methodological limitations and heterogeneity of design, analysis and reporting both hamper data synthesis and create potential for misinterpretation of findings. Using data from a recent Australian study involving 42 015 ex-prisoners and 2329 observed deaths, we quantify the variation in findings associated with various approaches. RESULTS: We identified 29 publications based on 25 separate studies published 1998-2011, mainly from the United Kingdom, United States and Australia. Mortality estimates varied systematically according to features of study design and data analysis. A number of common, avoidable and significant methodological limitations were identified. Substantial heterogeneity in study design, methods of data analysis and reporting of findings was observed. CONCLUSIONS: Record linkage studies examining mortality in ex-prisoners show widely varying estimates that are influenced substantially by avoidable methodological limitations and reducible heterogeneity. Future studies should adopt best practice methods and more consistent methods of analysis and reporting, to maximize policy relevance and impact.
Addiction 11/2012; · 4.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Objective. This article reviews panel studies of air pollution on children's respiratory health and proposes future research directions. Methods. The PubMed electronic database was used to search published original epidemiological studies in peer-reviewed journals from 2000 to November 2011. Children's age was limited to ≤18 years old. A total of 33 relevant articles were obtained, with 20 articles relating to lung function, 21 articles relating to respiratory symptoms, and 8 articles examining both. Results. Most studies suggested the adverse effects of air pollution on children's lung function and respiratory symptoms. Particles and NO(2) showed more significant results, whereas effects of SO(2) were not consistent. A few studies indicated that O(3) interacted with temperature and sometimes seemed to be a protective factor for children's respiratory health. Negative associations between air pollutants and pulmonary health were more serious in asthmatic children than in healthy subjects. However, many outcomes depended on the number of lag days. Peak expiratory flow (PEF) was the most usual measurement for children's lung function, followed by forced expiratory volume in 1 second (FEV(1)). Conclusions. There are significant adverse effects of air pollution on children's pulmonary health, especially for asthmatics. Future studies need to examine the lag effects of air pollution on children's lung function and respiratory symptoms. Ambient temperature is predicted to change worldwide due to climate change, which will threaten population health. Further research is needed to examine the effects of ambient temperature and the interactive effects between air pollution and ambient temperature on children's lung function and respiratory symptoms.
Journal of Asthma 09/2012; 49(9):895-910. · 1.52 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: A large phase III placebo-controlled, randomized efficacy trial of an investigational 11-valent pneumococcal conjugate vaccine against pneumonia in children less than 2 years of age was conducted in the Philippines from July 2000 to December 2004. Clinical data from 12,194 children who were given either study vaccine or placebo was collected from birth up to two years of age for the occurrence of radiologically proven pneumonia as the primary endpoint, and for clinical pneumonia and invasive pneumococcal disease as the secondary endpoints. Several tertiary endpoints were also explored. Along the core trial, several satellite studies on herd immunity, cost-effectiveness of the study vaccine, acute otitis media, and wheezing were conducted.
We describe here in detail how the relevant clinical records were managed and how quality control procedures were implemented to ensure that valid data were obtained respectively for the core trial and for the satellite studies. We discuss how the task was achieved, what the challenges were and what might have been done differently.
There were several factors that made the task of data management doable and efficient. First, a pre-trial data management system was available. Secondly, local committed statisticians, programmers and support staff were available and partly familiar to clinical trials. Thirdly, the personnel had undergone training during trial and grew with the task they were supposed to do. Thus the knowledge needed to develop and operate clinical data system was fully transferred to local staff.
Current Controlled Trials ISRCTN62323832.
BMC Research Notes 06/2012; 5:274.
-
[show abstract]
[hide abstract]
ABSTRACT: Despite the importance of mortality data for effective planning and monitoring of health services, official reporting systems rarely capture every death. The completeness of death reporting and the subsequent effect on mortality estimates were examined in six municipalities of Bohol province in the Philippines using a system review and capture-recapture analysis.
Reports of deaths were collected from records at local civil registration offices, health centers and hospitals, and parish churches. Records were reconciled using a specific set of matching criteria, and both a two-source and a three-source capture-recapture analysis was conducted. For the two-source analysis, civil registry and health data were combined due to dependence between these sources and analyzed against the church data.
Significant dependence between civil registration and health reporting systems was identified. There were 8,075 unique deaths recorded in the study area between 2002 and 2007. We found 5% to 10% of all deaths were not reported to any source, while government records captured only 77% of all deaths. Life expectancy at birth (averaged for 2002-2007) was estimated at 65.7 years and 73.0 years for males and females, respectively. This was one to two years lower than life expectancy estimated from reconciled reported deaths from all sources, and four to five years lower than life expectancy estimated from civil registration data alone. Reporting patterns varied by age and municipality, with childhood deaths more underreported than adult deaths. Infant mortality was underreported in civil registration data by 62%.
Deaths are underreported in Bohol, with inconsistent reporting procedures contributing to this situation. Uncorrected mortality measures would subsequently be misleading if used for health planning and evaluation purposes. These findings highlight the importance of ensuring that official mortality estimates from the Philippines are derived from data that have been assessed for underreporting and corrected as necessary.
Population Health Metrics 01/2011; 9:9. · 2.11 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To determine whether pneumococcal carriage at the time of 11-valent pneumococcal conjugate vaccine (PCV-11) administration interferes with immune response in infants.
A total of 1111 Filipino infants recruited into an immunogenicity and carriage study, nested in an efficacy trial, received PCV-11 or saline solution placebo at 6, 10, and 14 weeks of age. Antibody concentrations to the most frequently carried vaccine serotypes 6B, 19F, and 23F were measured by enzyme immunoassay from sera obtained at 18 weeks and 9 months of age. Serotype-specific antibody concentration was compared between groups of children among PCV-11 recipients stratified according to their carriage status at 6 weeks of age.
Antibody concentrations to 6B, 19F, and 23F were significantly lower at 18 weeks and 9 months of age among children who were carriers of the specific serotype at 6 weeks of age than among non-carriers of the serotype. The hyporesponsiveness was specific to the carried serotype. The specific antibody concentrations induced by PCV-11 among carriers did not differ significantly from those in placebo recipients, whereas the differences were highly significant among noncarriers.
Pneumococcal carriage, prevalent in Filipino infants, interferes with serotype-specific immune response to primary series of PCV and has potential implications for immunization programs.
The Journal of pediatrics 11/2010; 157(5):778-83.e1. · 4.02 Impact Factor
-
Jo-An Atkinson,
Albino Bobogare,
Andrew Vallely,
Leonard Boaz,
Gerard Kelly,
William Basifiri,
Simon Forsyth,
Peter Baker,
Bridget Appleyard,
Hilson Toaliu, Gail Williams
[show abstract]
[hide abstract]
ABSTRACT: A key component of the malaria elimination strategy in Solomon Islands (SI) is widespread coverage of long-lasting insecticidal nets (LLINs). The success of this strategy is dependent on LLIN acceptability and compliance. There has been unresolved debate among policy makers and donors as to which type of LLIN would be most appropriate for large-scale distribution in SI, and anecdotal reports of a lack of acceptability of certain brands of LLINs. A cluster randomized controlled crossover bed net acceptability and preference trial was therefore carried out from July to September, 2008 to inform policy and to facilitate community engagement and participation in the selection of the most appropriate LLIN for use in SI.
A three-stage sampling method was used to randomly select the study population from Malaita Province, SI. Three brands of LLINs were assessed in this study: Olyset, PermaNet and DuraNet. Bed net acceptability and preference were evaluated through surveys at three defined time points after short and longer-term trial of each LLIN.
The acceptability of PermaNet after short-term use (96.5%) was significantly greater than Olyset (67.3%, p < 0.001) and DuraNet (69.8%, p < 0.001). The acceptability of DuraNet and Olyset after short-term use was not significantly different at the 5% level. LLINs that were perceived not to prevent mosquito bites were significantly less acceptable than LLINs that were perceived to prevent mosquito bites (OR 0.15; 95%CI 0.03 to 0.6). LLINs that allow a pleasant night's sleep (OR 6.3; 95%CI:3.3-12.3) and have a soft texture (OR 5.7; 95%CI:1.9-20.5) were considered more acceptable than those that did not. Olyset's acceptability decreased over time and this was due to net wrinkling/shrinkage after washing resulting in reduced efficiency in preventing mosquito bites. The increase in DuraNet acceptability was a result of a reduction in minor adverse events following longer-term use.
This research was conducted to inform LLIN procurement as part of the national malaria control and elimination programme in SI. The success of malaria elimination in the Pacific and elsewhere relies on provision of acceptable interventions, consideration of local-level realities and engagement of communities in strategy development.
Clinical trials ACTRN12608000322336.
Malaria Journal 12/2009; 8:298. · 3.19 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Pneumococcal pneumonia is a major cause of morbidity and mortality worldwide. Efficacy of pneumococcal conjugate vaccines (PCV) in reducing childhood pneumonia has been estimated in four double-blind, randomized, controlled trials. An investigational 11-valent pneumococcal conjugate vaccine (11PCV) had an efficacy of 22.9% against radiologically defined pneumonia during first 2 years of life in Filipino infants. We report here the immunogenicity of the vaccine in a nested study of 1111 infants randomized 1:1 to receive 11PCV or placebo scheduled to be given according to the National EPI Program at 6, 10, and 14 weeks of age.
IgG antibody concentrations to pneumococcal capsular polysaccharides were measured by a standardized enzyme immuno-assay in serum samples drawn post-3rd dose for peak antibody response and at the time of measles vaccination at 9 months of age for persistence of the antibodies.
The geometric mean concentrations (GMCs) of antibodies were significantly higher in 11PCV than in placebo recipients against vaccine serotypes at both sampling points. One month post-3rd dose, 93-100% of 11PCV recipients had > or =0.35microg/ml for 9 serotypes, 76% for 6B, and 87% for 23F. The same proportions varied between 24% and 97% at 9.5 months of age due to antibody decrease. GMC to vaccine-related serotype 19A, but not to 6A, was higher in 11PCV than in placebo recipients. 7-12% of the 11PCV recipients had spontaneous antibody increases to serotypes 6B, 23F, and 14 between the two sampling points. These serotypes were common in nasopharyngeal samples of the infants.
The 11PCV demonstrated good immunogenicity after three doses and persistence of antibodies at least up to 9.5 months of age, comparable to other PCVs that have been evaluated for efficacy against radiologically defined pneumonia in other populations.
Vaccine 06/2009; 27(20):2680-8. · 3.77 Impact Factor
-
Marilla G Lucero,
Hanna Nohynek, Gail Williams,
Veronica Tallo,
Eric A F Simões,
Socorro Lupisan,
Diozele Sanvictores,
Simon Forsyth,
Taneli Puumalainen,
Juanita Ugpo,
Marites Lechago,
Margaret de Campo,
Erma Abucejo-Ladesma,
Lydia Sombrero,
Antti Nissinen,
Anu Soininen,
Petri Ruutu,
Ian Riley,
Helen P Mäkelä
[show abstract]
[hide abstract]
ABSTRACT: Pneumococcus is a leading cause of childhood pneumonia worldwide. Pneumococcal conjugate vaccines (PCV) have demonstrated efficacy against childhood invasive pneumococcal disease (IPD) and pneumonia in the United States and Africa. No information is available from Asia on the impact of PCV on childhood pneumonia.
We conducted a randomized, placebo-controlled, double-blind trial in Bohol, the Philippines (ISRCTN 62323832). Children 6 weeks to <6 months of age were randomly allocated to receive 3 doses of either an 11-valent PCV (11PCV, sanofi pasteur, Lyon, France) or a saline placebo, with a minimum interval of 4 weeks between doses to determine vaccine efficacy (VE) against the primary outcome of a child experiencing first episode of community-acquired radiologically defined pneumonia in the first 2 years of life. Secondary end points were clinical pneumonia, IPD, safety, and immunogenicity.
Twelve thousand one hundred ninety-one children were enrolled. By per protocol (PP) analysis, 93 of 6013 fully vaccinated 11PCV recipient children had a first episode of radiologic pneumonia compared with 120 of 6018 placebo recipients. VE against radiologically defined pneumonia for the PP cohort of children 3 to 23 months old was 22.9% (95% CI: -1.1, 41.2; P = 0.06), for the prespecified subgroups of children 3 to 11 months of age, 34.0% (95% CI: 4.8, 54.3; P = 0.02), and of those 12 to 23 months old, 2.7% (95% CI: -43.5, 34.0; P = 0.88). By intent-to-treat (ITT) analysis, 119 of 6097 11PCV recipient children had an episode of radiologic pneumonia compared with 141 of 6094 placebo recipients. VE against radiologic pneumonia for the ITT cohort of children <2 years old was 16.0% (95% CI -7.3, 34.2; P = 0.16), for a subgroup of children <12 months of age, 19.8% (95% CI: -8.8, 40.8; P = 0.15). VE against clinical pneumonia by PP was not significant (VE 0.1%; 95% CI -9.4, 8.7; P = 0.99). IPD was rare: only 3 cases of IPD due to vaccine serotypes were observed during the study. 11PCV was immunogenic and well tolerated. Among 11PCV recipients, a small excess of serious adverse respiratory events was observed in the first 28 days after the first and second dose of vaccine, and of nonrespiratory events after the first dose. An excess of pneumonia episodes in 11PCV recipients in the month following the second dose of vaccination was the principal reason for lower VE by ITT analysis than by PP analysis.
In PP analysis, a 22.9% reduction of community-acquired radiologically confirmed pneumonia in children younger than 2 years of age in the 11-valent tetanus-diphtheria toxoid-conjugated PCV vaccinated group was observed; a reduction similar as observed in other PCV trials. We could not demonstrate any VE against clinical pneumonia. Our finding confirms for the first time that in a low-income, low-mortality developing country in Asia, at least one-fifth of radiologically confirmed pneumonia is caused by pneumococcus, and thus preventable by PCV. Whether PCV should be included in national program in such settings, however, depends on careful country specific disease burden measurement and cost-effectiveness calculation.
The Pediatric Infectious Disease Journal 06/2009; 28(6):455-62. · 3.58 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Pneumonia, caused by Streptococcus pneumoniae, is a major cause of morbidity and mortality among children in low-income countries. The effectiveness of pneumococcal conjugate vaccines (PCVs) against invasive pneumococcal disease (IPD), pneumonia, and mortality needs to be evaluated.
To update the 2004 review on the efficacy of PCVs in preventing vaccine-serotypes IPD (VT-IPD) , X-ray defined pneumonia among HIV-1 negative children, and other new outcomes.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, issue 1), which contains the Cochrane Acute Respiratory Infections Group's Specialised Register; MEDLINE (1990 to Week 4 February 2009); and EMBASE (1974 to March 2009).
Randomised controlled trials (RCTs) comparing PCV with placebo, or another vaccine, in children under two with IPD and clinical / radiographic pneumonia as outcomes.
Two review authors independently identified studies, extracted data, and evaluated their corresponding risks of bias. Differences were resolved by discussion. Meta-analysis used the inverse variance method.
We identified 11 publications from six RCTs conducted in Africa, US, Philippines and Finland where 57,015 children received PCV; while 56,029 received placebo or another vaccine. Seven publications provided high quality evidence on PCV efficacy against IPD and four provided moderate quality evidence against pneumonia. None of the five trials with all-cause mortality data were powered to investigate this outcome. Only two trials have data on all-cause admissions.The main analysis for this review involved HIV-1 negative children and used the pooled results of random-effects model, intent-to-treat analysis (ITT).Pooled vaccine efficacy (VE) for VT-IPD was 80% (95% confidence interval (CI) 58% to 90%, P < 0.0001); all serotypes-IPD, 58% (95% CI 29% to 75%, P = 0.001); World Health Organization X-ray defined pneumonia was 27% (95% CI 15% to 36%, P < 0.0001); clinical pneumonia, 6% (95% CI 2% to 9%, P = 0.0006); and all-cause mortality, 11% (95% CI -1% to 21%, P = 0.08). Analysis involving HIV-1 positive children had similar findings.
PCV is effective in preventing IPD, X-ray defined pneumonia, and clinical pneumonia among HIV-1 negative and HIV-1 positive children under two years. The impact was greater for VT-IPD than for all serotypes-IPD, and for X-ray defined pneumonia than for clinical pneumonia. An 11% reduction with a 95% CI of -1% to 21% and a P = 0.08 is compatible with reduction in all-cause mortality.
Cochrane database of systematic reviews (Online) 01/2009; · 5.72 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In a phase three randomized, double-blind, saline-placebo controlled study conducted in Bohol, Philippines, we assessed the reactogenicity of an 11-valent PCV (11PCV) when given simultaneously with EPI vaccines at 6, 10 and 14 weeks of age in a subset of 252 and 126 children who were followed-up by passive and active surveillance, respectively. In passive surveillance (parents' observation), redness was observed in 14.4% vs. 11.8%, swelling in 8% vs. 3.9%, induration in 13.6% vs. 8.6%, and pain in 54.4% vs. 47.2% of 11PCV and placebo infants, respectively, after the first dose of the vaccine. Redness at injection site was significantly more common with 11PCV than placebo infants after the third dose (13.6% vs. 3.2%, p=0.005). Crying (53.6% vs. 48%), irritability (48% vs. 46.4%), and fever (22.4% vs. 19.6%) were commonly observed in 11PCV and placebo infants, respectively, after the first dose. Loss of appetite was significantly more common among 11PCV (12%) than placebo (4.7%) infants but only after the first dose of the vaccine (P=0.04). The number of reactions decreased in both groups with subsequent doses. The non-adjuvanted 11PCV vaccine was found to be well-tolerated among Filipino infants.
Vaccine 11/2008; 27(20):2723-9. · 3.77 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To obtain, through a survey, estimates of immunisation coverage in a birth cohort of Indigenous children, and to compare survey estimates with those obtained from the Australian Childhood Immunisation Register (ACIR) for the same birth cohort of Indigenous children.
Cluster sampling of a birth cohort of two-year-old Indigenous children across Queensland, stratified according to accessibility/remoteness from services, was undertaken in 2003. An innovative method of identifying participants was used. Survey results of 10 vaccine doses were compared with ACIR data.
The survey obtained a 4% sample of the birth cohort (137 children). Universally recommended vaccines showed high levels of coverage at 12 and 24 months, and survey estimates were slightly higher than ACIR estimates. Diphtheria-tetanus-acellular pertussis vaccine dose 3 (DTPa3) coverage was 93.8% (95% CI 88.0-99.6) by 12 months on survey and 87.5% on ACIR. Coverage was not timely and a lag phase of 4-6 months occurred for each vaccine dose. Haemophilus influenzae type b vaccine dose 2 (Hib2), scheduled for the age of four months, reached 90% coverage by nine months of age in the survey children.
Both methods reported here provided similar results.
These data indicate that ACIR Indigenous reporting rates have increased and coverage estimates are comparable to those provided by a survey. Immunisation coverage appears to be high, and the main remaining challenge in further reducing vaccine-preventable disease in Indigenous children is to improve immunisation timeliness.
Australian and New Zealand Journal of Public Health 03/2007; 31(1):67-72. · 1.20 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In Filipino infants, 1 dose of an adjuvanted, 11-valent pneumococcal conjugate vaccine (serotypes 1, 4, 5, 7F, 9V, 19F, and 23F conjugated to tetanus protein; and serotypes 3, 6B, 14, and 18C conjugated to diphtheria toxoid) administered alone at age 18 weeks (11PncTD1) elicited similar antibody concentrations at age 9 months as those elicited by 3 doses (11PncTD3) administered concomitantly with national program vaccines, at ages 6, 10, and 14 weeks. Geometric mean antibody concentrations ranged from 0.36 microg/mL (for serotype 18C) to 5.81 microg/mL (for serotype 4), for the 11PncTD1 vaccine, and from 0.32 microg/mL (for serotype 18C) to 5.01 microg/mL (for serotype 19F), for the 11PncTD3 vaccine. The proportion of infants with threshold antibody concentrations > or =0.35 microg/mL was also similar (ranges, 55.6%-100% for the 11PncTD1 vaccine and 42.9%-100% for the 11PncTD3 vaccine). The functional activity of antibodies expressed as opsonophagocytic activity titers was similar in the 11PncTD1 and 11PncTD3 groups. This finding is an important one for countries with financial constraints and high pneumococcal disease burden.
The Journal of Infectious Diseases 07/2004; 189(11):2077-84. · 6.41 Impact Factor
-
The Lancet 365(9465):1113-4. · 38.28 Impact Factor
-
-
[show abstract]
[hide abstract]
ABSTRACT: In this article, we discuss the ethical positions adopted within universities, by communities and by research funding agencies to negotiate the roles of academics and others in conducting research, identifying mechanisms for community involvement, establishing ongoing consultative procedures, and clarifying areas for enquiry. Within the Australian Longitudinal Study on Women's Health, we have adopted different strategies with the various immigrant and Indigenous communities with whom we work.
-
[show abstract]
[hide abstract]
ABSTRACT: In Filipino infants, 1 dose of an adjuvanted, 11-valent pneumococcal conjugate vaccine (serotypes 1, 4, 5, 7F, 9V, 19F, and 23F conjugated to tetanus protein; and serotypes 3, 6B, 14, and 18C conjugated to diphtheria toxoid) administered alone at age 18 weeks (11PncTD1) elicited similar antibody concentrations at age 9 months as those elicited by 3 doses (11PncTD3) administered concomitantly with national program vaccines, at ages 6, 10, and 14 weeks. Geometric mean antibody concentrations ranged from 0.36 mug/mL ( for serotype 18C) to 5.81 mug/mL (for serotype 4), for the 11PncTD1 vaccine, and from 0.32 mug/mL (for serotype 18C) to 5.01 mug/mL (for serotype 19F), for the 11PncTD3 vaccine. The proportion of infants with threshold antibody concentrations greater than or equal to0.35 mug/mL was also similar (ranges, 55.6%-100% for the 11PncTD1 vaccine and 42.9%-100% for the 11PncTD3 vaccine). The functional activity of antibodies expressed as opsonophagocytic activity titers was similar in the 11PncTD1 and 11PncTD3 groups. This finding is an important one for countries with financial constraints and high pneumococcal disease burden.
