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Health Technology Assessment | 2012

Effectiveness and cost-effectiveness of computer and other electronic aids for smoking cessation: a systematic review and network meta-analysis

Yen-Fu Chen; Jason Madan; Nicky J Welton; Ismail Yahaya; Paul Aveyard; Linda Bauld; Dechao Wang; A Fry-Smith; Marcus R. Munafò

BACKGROUND Smoking is harmful to health. On average, lifelong smokers lose 10 years of life, and about half of all lifelong smokers have their lives shortened by smoking. Stopping smoking reverses or prevents many of these harms. However, cessation services in the NHS achieve variable success rates with smokers who want to quit. Approaches to behaviour change can be supplemented with electronic aids, and this may significantly increase quit rates and prevent a proportion of cases that relapse. OBJECTIVE The primary research question we sought to answer was: What is the effectiveness and cost-effectiveness of internet, pc and other electronic aids to help people stop smoking? We addressed the following three questions: (1) What is the effectiveness of internet sites, computer programs, mobile telephone text messages and other electronic aids for smoking cessation and/or reducing relapse? (2) What is the cost-effectiveness of incorporating internet sites, computer programs, mobile telephone text messages and other electronic aids into current nhs smoking cessation programmes? and (3) What are the current gaps in research into the effectiveness of internet sites, computer programs, mobile telephone text messages and other electronic aids to help people stop smoking? DATA SOURCES For the effectiveness review, relevant primary studies were sought from The Cochrane Library [Cochrane Central Register of Controlled Trials (CENTRAL)] 2009, Issue 4, and MEDLINE (Ovid), EMBASE (Ovid), PsycINFO (Ovid), Health Management Information Consortium (HMIC) (Ovid) and Cumulative Index to Nursing and Allied Health Literature (CINAHL) (EBSCOhost) from 1980 to December 2009. In addition, NHS Economic Evaluation Database (NHS EED) and Database of Abstracts of Reviews of Effects (DARE) were searched for information on cost-effectiveness and modelling for the same period. Reference lists of included studies and of relevant systematic reviews were examined to identify further potentially relevant studies. Research registries of ongoing studies including National Institute for Health Research (NIHR) Clinical Research Network Portfolio Database, Current Controlled Trials and ClinicalTrials.gov were also searched, and further information was sought from contacts with experts. REVIEW METHODS Randomised controlled trials (RCTs) and quasi-RCTs evaluating smoking cessation programmes that utilise computer, internet, mobile telephone or other electronic aids in adult smokers were included in the effectiveness review. Relevant studies of other design were included in the cost-effectiveness review and supplementary review. Pair-wise meta-analyses using both random- and fixed-effects models were carried out. Bayesian mixed-treatment comparisons (MTCs) were also performed. A de novo decision-analytical model was constructed for estimating the cost-effectiveness of interventions. Expected value of perfect information (EVPI) was calculated. Narrative synthesis of key themes and issues that may influence the acceptability and usability of electronic aids was provided in the supplementary review. RESULTS This effectiveness review included 60 RCTs/quasi-RCTs reported in 77 publications. Pooled estimate for prolonged abstinence [relative risk (RR) = 1.32, 95% confidence interval (CI) 1.21 to 1.45] and point prevalence abstinence (RR = 1.14, 95% CI 1.07 to 1.22) suggested that computer and other electronic aids increase the likelihood of cessation compared with no intervention or generic self-help materials. There was no significant difference in effect sizes between aid to cessation studies (which provide support to smokers who are ready to quit) and cessation induction studies (which attempt to encourage a cessation attempt in smokers who are not yet ready to quit). Results from MTC also showed small but significant intervention effect (time to relapse, mean hazard ratio 0.87, 95% credible interval 0.83 to 0.92). Cost-threshold analyses indicated some form of electronic intervention is likely to be cost-effective when added to non-electronic behavioural support, but there is substantial uncertainty with regard to what the most effective (thus most cost-effective) type of electronic intervention is, which warrants further research. EVPI calculations suggested the upper limit for the benefit of this research is around £ 2000-3000 per person. LIMITATIONS The review focuses on smoking cessation programmes in the adult population, but does not cover smoking cessation in adolescents. Most available evidence relates to interventions with a single tailored component, while evidence for different modes of delivery (e.g. e-mail, text messaging) is limited. Therefore, the findings of lack of sufficient evidence for proving or refuting effectiveness should not be regarded as evidence of ineffectiveness. We have examined only a small number of factors that could potentially influence the effectiveness of the interventions. A comprehensive evaluation of potential effect modifiers at study level in a systematic review of complex interventions remains challenging. Information presented in published papers is often insufficient to allow accurate coding of each intervention or comparator. A limitation of the cost-effectiveness analysis, shared with several previous cost-effectiveness analyses of smoking cessation interventions, is that intervention benefit is restricted to the first quit attempt. Exploring the impact of interventions on subsequent attempts requires more detailed information on patient event histories than is available from current evidence. CONCLUSIONS Our effectiveness review concluded that computer and other electronic aids increase the likelihood of cessation compared with no intervention or generic self-help materials, but the effect is small. The effectiveness does not appear to vary with respect to mode of delivery and concurrent non-electronic co-interventions. Our cost-effectiveness review suggests that making some form of electronic support available to smokers actively seeking to quit is highly likely to be cost-effective. This is true whether the electronic intervention is delivered alongside brief advice or more intensive counselling. The key source of uncertainty is that around the comparative effectiveness of different types of electronic interventions. Our review suggests that further research is needed on the relative benefits of different forms of delivery for electronic aids, the content of delivery, and the acceptability of these technologies for smoking cessation with subpopulations of smokers, particularly disadvantaged groups. More evidence is also required on the relationship between involving users in the design of interventions and the impact this has on effectiveness, and finally on how electronic aids developed and tested in research settings are applied in routine practice and in the community.


BMC Pregnancy and Childbirth | 2008

A population-based study of effect of multiple birth on infant mortality in Nigeria

Olalekan A. Uthman; Mubashir B Uthman; Ismail Yahaya

BackgroundMulti-foetal pregnancies and multiple births including twins and higher order multiples births such as triplets and quadruplets are high-risk pregnancy and birth. These high-risk groups contribute to the higher rate of childhood mortality especially during early period of life.MethodsWe examined the relationship between multiple births and infant mortality using univariable and multivariable survival regression procedure with Weibull hazard function, controlling for childs sex, birth order, prenatal care, delivery assistance; mothers age at child birth, nutritional status, education level; household living conditions and several other risk factors.ResultsChildren born multiple births were more than twice as likely to die during infancy as infants born singleton (hazard ratio = 2.19; 95% confidence interval: 1.50, 3.19) holding other factors constant. Maternal education and household asset index were associated with lower risk of infant mortality.ConclusionMultiple births are strongly negatively associated with infant survival in Nigeria independent of other risk factors. Mothers education played a protective role against infant death. This evidence suggests that improving maternal education may be key to improving child survival in Nigeria. A well-educated mother has a better chance of satisfying important factors that can improve infant survival: the quality of infant feeding, general care, household sanitation, and adequate use of preventive and curative health services.


Value in Health | 2011

The cost-utility analysis of adult male circumcision for prevention of heterosexual acquisition of HIV in men in sub-Saharan Africa: a probabilistic decision model

Olalekan A. Uthman; Taiwo Aderemi Popoola; Ismail Yahaya; Mubashir B Uthman; Olatunde Aremu

OBJECTIVE The aim of this study was to assess the cost-utility of adult male circumcision (AMC) versus no AMC in the prevention of heterosexual acquisition of HIV in men in sub-Saharan Africa. METHODS A decision tree was constructed and parameterized using data from published sources. The economic evaluation was conducted from the perspective of government health care payer. Benefits (disability adjusted life years [DALYs]) and costs were discounted at 3%. Costs were assessed in 2008 US dollars. One-way and probabilistic sensitivity analyses were conducted to assess the stability of the base-case results. The uncertainty surrounding the estimates of cost effectiveness was illustrated through a cost-effectiveness acceptability curve and cost-effectiveness plane. RESULTS In the base-case analysis, AMC can be regarded as cost saving because it is associated with higher DALYs gained and lower costs than no AMC. The probability that AMC is cost effective is above 0.96 at a threshold value of


BMC International Health and Human Rights | 2013

Social disorganization and history of child sexual abuse against girls in sub-Saharan Africa: a multilevel analysis

Ismail Yahaya; Olalekan A. Uthman; Joaquim Soares; Gloria Macassa

150 and remains high over a wide range of threshold values. Thus, there is very little uncertainty surrounding the decision to adopt AMC for prevention of heterosexual acquisition of HIV in men. The results were found to be sensitive to varying any of the following parameters: DALYs averted, discount, and circumcision efficacy. CONCLUSIONS AMC is found to be cost saving. AMC may be seen as a promising new form of strategy for prevention of heterosexual acquisition of HIV in men, but should never replace other known methods of HIV prevention and should always be considered as part of a comprehensive HIV prevention package.


Journal of Public Health | 2012

Exploring variations in under-5 mortality in Nigeria using league table, control chart and spatial analysis

Olalekan A. Uthman; Victor Aiyedun; Ismail Yahaya

BackgroundChild sexual abuse (CSA) is a considerable public health problem. Less focus has been paid to the role of community level factors associated with CSA. The aim of this study was to examine the association between neighbourhood-level measures of social disorganization and CSA.MethodsWe applied multiple multilevel logistic regression analysis on Demographic and Health Survey data for 6,351 adolescents from six countries in sub-Saharan Africa between 2006 and 2008.ResultsThe percentage of adolescents that had experienced CSA ranged from 1.04% to 5.84%. There was a significant variation in the odds of reporting CSA across the communities, suggesting 18% of the variation in CSA could be attributed to community level factors. Respondents currently employed were more likely to have reported CSA than those who were unemployed (odds ratio [OR] = 2.05, 95% confidence interval [CI] 1.48 to 2.83). Respondents from communities with a high family disruption rate were 57% more likely to have reported CSA (OR=1.57, 95% CI 1.14 to 2.16).ConclusionWe found that exposure to CSA was associated with high community level of family disruption, thus suggesting that neighbourhoods may indeed have significant important effects on exposure to CSA. Further studies are needed to explore pathways that connect the individual and neighbourhood levels, that is, means through which deleterious neighbourhood effects are transmitted to individuals.


Journal of Injury and Violence Research | 2014

Individual and community-level socioeconomic position and its association with adolescents experience of childhood sexual abuse: a multilevel analysis of six countries in Sub-Saharan Africa

Ismail Yahaya; Antonio Ponce de Leon; Olalekan A. Uthman; Joaquim Soares; Gloria Macassa

BACKGROUND Under-5 mortality rate (U5MR) is the probability of a child born in a specific year or period dying before reaching the age of 5. Nigeria has a high rate of U5MR and accounts for a significant proportion of the high U5MR in sub-Sahara Africa. There are differences in health and social practice in the different states in Nigeria, coupled with the differences in developmental priorities of each State government. There is therefore the need to identify the states with high and low U5MR, to further explore the risk factors and make recommendations for planning. This study investigates variation in U5MR in Nigeria using Shewharts theory of variation and control charts. METHODS We used data from the birth histories included in the 2008 Nigerian Demographic and Health Survey to estimate U5MR using a synthetic cohort life table. We plotted control charts of the proportion of under-5 mortality for the 37 states (included federal capital Abuja) in Nigeria. The Local Indicators of Spatial Association was used as a measure of the overall clustering and is assessed by a test of a null hypothesis. RESULTS On average, more than 1 in every 10 children born in Nigeria (159 per 1000 live births) does not survive to their fifth birthday. Kwara and Osun states had the lowest U5MR (less than 60 per 1000 live births), while Jigawa, Kano, Sokoto, Niger and Adamawa states had the highest U5MR (more than 200 per 1000 live births). There is a wide variation in the U5MR between the 37 states. The funnel plot identifies 27 (73%) states within the 99% control limits indicating common-cause variation. Four states were above the upper control limit (higher than the average) and six states were below the lower control limit (lower than the average), indicating special-cause variation. CONCLUSIONS U5MR is high in Nigeria; the rates are in three digits. There is a wide variation in the U5MR in Nigeria, with 27% showing evidence of special-cause variation which merits further investigation to identify possible causes. However, the vast majority of states (73%) are consistent with common-cause variation.


Malaria Journal | 2012

Socio-economic inequity in accessing malaria control interventions in Nigeria: analysis of changes between 2003 and 2008

AbdulGafar Alawode; Olalekan A. Uthman; Ismail Yahaya

Abstract: Background: Childhood sexual abuse (CSA) is a substantial global health and human rights problem and consequently a growing concern in sub-Saharan Africa. We examined the association between individual and community-level socioeconomic status (SES) and the likelihood of reporting CSA. Methods: We applied multiple multilevel logistic regression analysis on Demographic and Health Survey data for 6,351 female adolescents between the ages of 15 and 18 years from six countries in sub-Saharan Africa, between 2006 and 2008. Results: About 70% of the reported cases of CSA were between 14 and 17 years. Zambia had the highest proportion of reported cases of CSA (5.8%). At the individual and community level, we found that there was no association between CSA and socioeconomic position. This study provides evidence that the likelihood of reporting CSA cut across all individual SES as well as all community socioeconomic strata. Conclusions: We found no evidence of socioeconomic differentials in adolescents’ experience of CSA, suggesting that adolescents from the six countries studied experienced CSA regardless of their individual and community-level socioeconomic position. However, we found some evidence of geographical clustering, adolescents in the same community are subject to common contextual influences. Further studies are needed to explore possible effects of countries’ political, social, economic, legal, and cultural impact on childhood sexual abuse.


Journal of Aggression, Conflict and Peace Research | 2015

Childhood sexual abuse among girls and determinants of sexual risk behaviours in adult life in sub-Saharan Africa

Ismail Yahaya; Antonio Ponce de Leon; Olalekan A. Uthman; Joaquim Soares; Gloria Macassa

Background Malaria is the major health problem in Nigeria, accounting for 60% of outpatient consultations and 30% of hospital admission [1]. The Federal Ministry of Health (FMoH) of Nigeria has adopted cost-effective malaria control interventions as tools for achieving ambitious objective of halving malaria burden by 2013 as contained in the National Malaria Strategic Plan (NMSP). The interventions include prompt and effective case management, Insecticide Treated Net (ITN) and Intermittent Preventive Treatment (IPT) while parasitological diagnosis is an adjunct to effective case management. The coverage for these interventions is very low as only 8% of households own ITN, 1.1% of under five children with malaria have access to Artemisinin-based Combination Therapy (ACT) within 24 hours of onset of fever and only 6.5% of pregnant women have access to 2 doses of IPT [2].


Cochrane Database of Systematic Reviews | 2013

Interventions for HIV-associated nephropathy.

Ismail Yahaya; Olalekan A. Uthman; Muhammed Mubashir B Uthman

Purpose – The purpose of this paper is to investigate the relationship between child sexual abuse and sexual risk behaviours as well as its potential mediators. Design/methodology/approach – This cross-sectional study used data from a cross-sectional study from 12,800 women between 15 and 49 years of age included in the 2008 Nigerian Demographic and Health Survey. Structural equation modelling (SEM) was applied to assess the association between childhood sexual abuse (CSA) and sexual risk behaviours. Findings – The authors found that CSA was directly associated with sexual risk behaviours. In addition, the association between CSA and sexual risk behaviour was also partially mediated by alcohol and cigarette use. Research limitations/implications – The results show that being abused in childhood is important for the subsequent development of sexual risk behaviours in adulthood and the association is mediated by alcohol and cigarette use. Practical implications – The results may be helpful for policy makers...


International Journal of Health Geographics | 2009

A trend analysis and sub-regional distribution in number of people living with HIV and dying with TB in Africa, 1991 to 2006.

Olalekan A. Uthman; Ismail Yahaya; Khalid Ashfaq; Mubashir B Uthman

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Dechao Wang

University of Birmingham

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Linda Bauld

University of Stirling

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