Population health outcomes in Nigeria compared with other west African countries, 1998-2019: a systematic analysis for the Global Burden of Disease Study.

BACKGROUND: Population-level health and mortality data are crucial for evidence-informed policy but scarce in Nigeria. To fill this gap, we undertook a comprehensive assessment of the burden of disease in Nigeria and compared outcomes to other west African countries. METHODS: In this systematic analysis, using data and results of the Global Burden of Diseases, Injuries, and Risk Factors Study 2019, we analysed patterns of mortality, years of life lost (YLLs), years lived with disability (YLDs), life expectancy, healthy life expectancy (HALE), and health system coverage for Nigeria and 15 other west African countries by gender in 1998 and 2019. Estimates of all-age and age-standardised disability-adjusted life-years for 369 diseases and injuries and 87 risk factors are presented for Nigeria. Health expenditure per person and gross domestic product were extracted from the World Bank repository. FINDINGS: Between 1998 and 2019, life expectancy and HALE increased in Nigeria by 18% to 64·3 years (95% uncertainty interval [UI] 62·2-66·6), mortality reduced for all age groups for both male and female individuals, and health expenditure per person increased from the 11th to third highest in west Africa by 2018 (US$18·6 in 2001 to $83·75 in 2018). Nonetheless, relative outcomes remained poor; Nigeria ranked sixth in west Africa for age-standardised mortality, seventh for HALE, tenth for YLLs, 12th for health system coverage, and 14th for YLDs in 2019. Malaria (5176·3 YLLs per 100 000 people, 95% UI 2464·0-9591·1) and neonatal disorders (4818·8 YLLs per 100 000, 3865·9-6064·2) were the leading causes of YLLs in Nigeria in 2019. Nigeria had the fourth-highest under-five mortality rate for male individuals (2491·8 deaths per 100 000, 95% UI 1986·1-3140·1) and female individuals (2117·7 deaths per 100 000, 1756·7-2569·1), but among the lowest mortality for men older than 55 years. There was evidence of a growing non-communicable disease burden facing older Nigerians. INTERPRETATION: Health outcomes remain poor in Nigeria despite higher expenditure since 2001. Better outcomes in countries with equivalent or lower health expenditure suggest health system strengthening and targeted intervention to address unsafe water sources, poor sanitation, malnutrition, and exposure to air pollution could substantially improve population health. FUNDING: The Bill & Melinda Gates Foundation.

Epidemiology of physical inactivity in Nigeria: a systematic review and meta-analysis.

BACKGROUND: Physical activity is crucial to preventing noncommunicable diseases. This study aimed to provide up-to-date evidence on the epidemiology of insufficient physical activity across Nigeria to increase awareness and prompt relevant policy and public health response. METHODS: A systematic literature search of community-based studies on physical inactivity was conducted. We constructed a meta-regression epidemiologic model to determine the age-adjusted prevalence and number of physically inactive persons in Nigeria for 1995 and 2020. RESULTS: Fifteen studies covering a population of 13 814 adults met our selection criteria. The pooled crude prevalence of physically inactive persons in Nigeria was 52.0% (95% CI: 33.7-70.4), with prevalence in women higher at 55.8% (95% CI: 29.4-82.3) compared to men at 49.3% (95% CI: 24.7-73.9). Across settings, prevalence of physically inactive persons was significantly higher among urban dwellers (56.8%, 35.3-78.4) compared to rural dwellers (18.9%, 11.9-49.8). Among persons aged 20-79 years, the total number of physically inactive persons increased from 14.4 million to 48.6 million between 1995 and 2020, equivalent to a 240% increase over the 25-year period. CONCLUSIONS: A comprehensive and robust strategy that addresses occupational policies, town planning, awareness and information, and sociocultural and contextual issues is crucial to improving physical activity levels in Nigeria.

High mortality among tuberculosis patients on treatment in Nigeria: a retrospective cohort study.

BACKGROUND: Tuberculosis (TB) remains a leading cause of death in much of sub-Saharan Africa despite available effective treatment. Prompt initiation of TB treatment and access to antiretroviral therapy (ART) remains vital to the success of TB control. We assessed time to mortality after treatment onset using data from a large treatment centre in Nigeria. METHODS: We analysed a retrospective cohort of TB patients that commenced treatment between January 2010 and December 2014 in Aminu Kano Teaching Hospital. We estimated mortality rates per person-months at risk (pm). Cox proportional hazards model was used to determine risk factors for mortality. RESULTS: Among 1,424 patients with a median age of 36.6 years, 237 patients (16.6%) died after commencing TB treatment giving a mortality rate of 3.68 per 100 pm of treatment in this cohort. Most deaths occurred soon after treatment onset with a mortality rate of 37.6 per 100 pm in the 1st week of treatment. Risk factors for death were being HIV-positive but not on anti-retroviral treatment (ART) (aHR 1.39(1 · 04-1 · 85)), residence outside the city (aHR 3 · 18(2.28-4.45)), previous TB treatment (aHR 3.48(2.54-4.77)), no microbiological confirmation (aHR 4.96(2.69-9.17)), having both pulmonary and extra-pulmonary TB (aHR 1.45(1.03-2.02), and referral from a non-programme linked clinic/centre (aHR 3.02(2.01-4.53)). CONCLUSIONS: We attribute early deaths in this relatively young cohort to delay in diagnosis and treatment of TB, inadequate treatment of drug-resistant TB, and poor ART access. Considerable expansion and improvement in quality of diagnosis and treatment services for TB and HIV are needed to achieve the sustainable development goal of reducing TB deaths by 95% by 2035.

Blood and body fluids exposure, post-exposure prophylaxis, and HIV self-testing among healthcare workers in northern Nigeria.

INTRODUCTION: In high-HIV burden settings, such as Nigeria, HIV self-testing and post-exposure prophylaxis (PEP) are often recommended, but not widely practiced. This study aims to identify the predictors of PEP utilization and preferences for HIV self-testing among healthcare workers in Nigeria. METHODS: A total of 403 healthcare workers from a tertiary hospital in Nigeria completed questionnaires. Adjusted odds ratios were derived from logistic regression models. RESULTS: Among the respondents, 141 (35.0%) reported experiencing at least one workplace exposure incident, with 72 (51.1%) of them receiving PEP. The majority of healthcare workers (n = 354, 87.8%) expressed a preference for HIV self-testing over traditional HIV testing and counseling. The occurrence of exposure incidents was predicted by the respondent's sex (adjusted odds ratio [aOR] = 1.25; 95% confidence interval [CI]: 1.15-3.08, female vs. male), age (aOR = 0. 16; 95% CI: 0.03-0.92, >40 vs. <30 years), profession (aOR = 1.88; 95% CI: 1.18-4.66, nurse/midwife vs. physician), work unit (aOR = 0.06; 95% CI: 0.02-0.23, obstetrics/gynecology vs. surgery), and previous HIV testing and counseling (aOR = 0.01; 95% Cl: 0.004-0.03, no vs. yes). Respondent's profession, work unit, and previous HIV testing and counseling independently predicted a preference for HIV self-testing. CONCLUSION: Further exploration of the feasibility of implementing HIV self-testing as an alternative to traditional HIV testing and counseling for workplace exposures is warranted.

Estimating the prevalence of COPD in an African country: evidence from southern Nigeria.

# Background: Though several environmental and demographic factors would suggest a high burden of chronic obstructive pulmonary disease (COPD) in most African countries, there is insufficient country-level synthesis to guide public health policy. # Methods: A systematic search of MEDLINE, EMBASE, Global Health and African Journals Online identified studies reporting the prevalence of COPD in Nigeria. We provided a detailed synthesis of study characteristics, and overall median and interquartile range (IQR) of COPD prevalence in Nigeria by case definitions (spirometry or non-spirometry). # Results: Of 187 potential studies, eight studies (6 spirometry and 2 non-spirometry) including 4,234 Nigerians met the criteria. From spirometry assessment, which is relatively internally consistent, the median prevalence of COPD in Nigeria was 9.2% (interquartile range, IQR: 7.6-10.0), compared to a lower prevalence (5.1%, IQR: 2.2-15.4) from studies based on British Medical Research Council (BMRC) criteria or doctor's diagnosis. The median prevalence of COPD was almost the same among rural (9.5%, IQR: 7.6-10.3) and urban dwellers (9.0%, IQR: 5.3-9.3) from spirometry studies. # Conclusions: A limited number of studies on COPD introduces imprecision in prevalence estimates and presents concerns on the level of response available across different parts of Nigeria, and indeed across many countries in sub-Saharan Africa.

Estimating the prevalence of overweight and obesity in Nigeria in 2020: a systematic review and meta-analysis.

BACKGROUND: Targeted public health response to obesity in Nigeria is relatively low due to limited epidemiologic understanding. We aimed to estimate nationwide and sub-national prevalence of overweight and obesity in the adult Nigerian population. METHODS: MEDLINE, EMBASE, Global Health, and Africa Journals Online were systematically searched for relevant epidemiologic studies in Nigeria published on or after 01 January 1990. We assessed quality of studies and conducted a random-effects meta-analysis on extracted crude prevalence rates. Using a meta-regression model, we estimated the number of overweight and obese persons in Nigeria in the year 2020. RESULTS: From 35 studies (n = 52,816), the pooled crude prevalence rates of overweight and obesity in Nigeria were 25.0% (95% confidence interval, CI: 20.4-29.6) and 14.3% (95% CI: 12.0-15.5), respectively. The prevalence in women was higher compared to men at 25.5% (95% CI: 17.1-34.0) versus 25.2% (95% CI: 18.0-32.4) for overweight, and 19.8% (95% CI: 3.9-25.6) versus 12.9% (95% CI: 9.1-16.7) for obesity, respectively. The pooled mean body mass index (BMI) and waist circumference were 25.6 kg/m2 and 86.5 cm, respectively. We estimated that there were 21 million and 12 million overweight and obese persons in the Nigerian population aged 15 years or more in 2020, accounting for an age-adjusted prevalence of 20.3% and 11.6%, respectively. The prevalence rates of overweight and obesity were consistently higher among urban dwellers (27.2% and 14.4%) compared to rural dwellers (16.4% and 12.1%). CONCLUSIONS: Our findings suggest a high prevalence of overweight and obesity in Nigeria. This is marked in urban Nigeria and among women, which may in part be due to widespread sedentary lifestyles and a surge in processed food outlets, largely reflective of a trend across many African settings.KEY MESSAGESAbout 12 million persons in Nigeria were estimated to be obese in 2020, with prevalence considerably higher among women. Nutritional and epidemiological transitions driven by demographic changes, rising income, urbanization, unhealthy lifestyles, and consumption of highly processed diets appear to be driving an obesity epidemic in the country.

Prevalence, awareness, treatment, and control of hypertension in Nigeria in 1995 and 2020: A systematic analysis of current evidence.

Improved understanding of the current burden of hypertension, including awareness, treatment, and control, is needed to guide relevant preventative measures in Nigeria. A systematic search of studies on the epidemiology of hypertension in Nigeria, published on or after January 1990, was conducted. The authors employed random-effects meta-analysis on extracted crude hypertension prevalence, and awareness, treatment, and control rates. Using a meta-regression model, overall hypertension cases in Nigeria in 1995 and 2020 were estimated. Fifty-three studies (n = 78 949) met our selection criteria. Estimated crude prevalence of pre-hypertension (120-139/80-89 mmHg) in Nigeria was 30.9% (95% confidence interval [CI]: 22.0%-39.7%), and the crude prevalence of hypertension (≥140/90 mmHg) was 30.6% (95% CI: 27.3%-34.0%). When adjusted for age, study period, and sample, absolute cases of hypertension increased by 540% among individuals aged ≥20 years from approximately 4.3 million individuals in 1995 (age-adjusted prevalence 8.6%, 95% CI: 6.5-10.7) to 27.5 million individuals with hypertension in 2020 (age-adjusted prevalence 32.5%, 95% CI: 29.8-35.3). The age-adjusted prevalence was only significantly higher among men in 1995, with the gap between both sexes considerably narrowed in 2020. Only 29.0% of cases (95% CI: 19.7-38.3) were aware of their hypertension, 12.0% (95% CI: 2.7-21.2) were on treatment, and 2.8% (95% CI: 0.1-5.7) had at-goal blood pressure in 2020. Our study suggests that hypertension prevalence has substantially increased in Nigeria over the last two decades. Although more persons are aware of their hypertension status, clinical treatment and control rates, however, remain low. These estimates are relevant for clinical care, population, and policy response in Nigeria and across Africa.

Using the consolidated framework for implementation research (CFIR) to assess the implementation context of a quality improvement program to reduce missed opportunities for vaccination in Kano, Nigeria: a mixed methods study.

Background: Although understanding implementation context is essential, there is a dearth of research on how to systematically explore it in quality improvement (QI) programs. Therefore, in this study, we used the consolidated framework for implementation research (CFIR) to guide a systematic evaluation of the implementation context of an ongoing QI program in order to generate rapid site-specific feedback that can be used to improve subsequent plan-do-study-act (PDSA) cycles.Methods: Formative cross-case evaluation was conducted using convergent mixed methods design. The study was conducted in five primary health care (PHC) facilities (PHC 1, PHC 3, PHC 5, PHC 9 and PHC 10) implementing the QI program. Health workers in those facilities formed the study population. Quantitative data were collected using a self-administered, Likert-based rating tool, while qualitative data collection was guided by an interview guide. The interviews were transcribed verbatim, and thematic analysis was performed. Raw median score and factor scores were computed. Methodological integration occurred at the design, analysis and reporting stage.Results: A total of 165 health workers were included in this study with a mean age of 33.43 years (standard deviation of 7.15). Majority were females and they all had post-secondary education. Health workers in two facilities; PHC 1 and PHC 5, reported higher score for the QI program across all five domains of CFIR. Implementation facilitators included intervention flexibility, relative advantage, self-efficacy among health workers, health workers confidence in the intervention, services integration. While implementation barriers included vaccine stock out, faulty cold chain infrastructure, lack of incentives, and socio-cultural beliefs.Conclusion: This study demonstrated that theory-driven formative evaluation can be integrated in QI programs in a low resource setting. It buttressed the value in conducting such assessment as they can be used to generate rapid feedback on factors that influence implementation success which can then be addressed in subsequent cycles.

Assessing readiness to implement routine immunization among patent and proprietary medicine vendors in Kano, Nigeria: a theory-informed cross-sectional study.

BACKGROUND: Patent and proprietary medicine vendors (PPMVs) are widespread in communities and can potentially be used to expand access to routine immunization especially in underserved areas. In this study, we aimed to assess their readiness to implement routine immunization in Kano, Nigeria and identify factors associated with it. METHODS: We conducted a cross-sectional survey of PPMVs aged 18 years and above in Kano metropolis, Nigeria, using cluster sampling technique. A 10-item Likert scale-based measure was used to estimate readiness score. The relationship between selected factors and readiness score was examined using multilevel linear modeling technique. RESULTS: A total of 455 PPMVs with median age of 36 years participated in the study. The median raw score for readiness was 4.7 (IQR: 4.3 - 4-8) (maximum obtainable was 5). The mean readiness score (obtained through factor analysis) was 5.28 (SD: 0.58). Readiness score was associated with factors such as knowledge of immunization and task demand, engagement by other public health programs among others. CONCLUSION: This study demonstrated the feasibility of measuring the level of readiness for implementing routine immunization among PPMVs. Given the high level of readiness, policy makers should consider the possibility of expanding access to immunization through PPMVs.

Factors influencing non-prescription sales of antibiotics among patent and proprietary medicine vendors in Kano, Nigeria: a cross-sectional study.

Patent and proprietary medicine vendors (PPMVs) increase access to antibiotics through non-prescription sales in their drug retail outlets. This fosters irrational antibiotic use among people, thus contributing to the growing burden of resistance. Although training programmes on antibiotic use and resistance exist, they have disproportionately targeted health workers in hospital settings. It's unclear if there is a relationship between such trainings and non-prescription sales of antibiotics among PPMVs which are more embedded in communities. Therefore, a cross-sectional study was conducted to elicit the determinants of non-prescription antibiotic sales among PPMVs in Kano metropolis, Nigeria. Through brainstorming, causal loop diagrams (CLDs) were used to illustrate the dynamics of factors that are responsible for non-prescription antibiotic sales. Multilevel logistic regression model was used to determine the relationship between training on antibiotic use and resistance and non-prescription antibiotic sales, after controlling for potential confounders. We found that two-third (66.70%) of the PPMVs reported that they have sold non-prescribed antibiotics. A total of three CLDs were constructed to illustrate the complex dynamics of the factors that are related to non-prescription antibiotic sales. After controlling for all factors, PPMVs who reported that they had never received any training on antibiotic use and resistance were twice as more likely to sell antibiotic without prescription compared with those who reported that they have ever received such training (OR = 2.07, 95% CI: 1.27-3.37). This finding suggests that there is an association between training on antibiotic use and resistance and non-prescription sales of antibiotics. However, the complex dynamics of the factors should not be ignored as it can have implications for the development of intervention programmes. Multifaceted and multicomponent intervention packages (incorporating trainings on antibiotic use and resistance) that account for the inherent complexity within the system are likely to be more effective for this setting.

Project OPUS: Development and evaluation of an electronic platform for pain management education of medical undergraduates in resource-limited settings.

INTRODUCTION: Pain is a very frequent symptom that is reported by patients when they present to health professionals but remains undertreated or untreated, particularly in low-resource settings including Nigeria. Lack of training in pain management remains the most significant obstacle to pain treatment alongside an inadequate emphasis on pain education in undergraduate medical curricula, negatively impacting on subsequent care of patients. This study aimed to determine the effect of a 12-week structured e-Learning course on the knowledge of pain management among Nigerian undergraduate medical students. METHODS: Prospective, multisite, pre-post study conducted across five medical colleges in Nigeria. Structured modules covering aspects of pain management were delivered on an e-Learning platform. Pre- and post-test self-assessments were carried out in the 12-week duration of the study. User experience questionnaires and qualitative interviews were conducted via instant messaging to evaluate user experiences of the platform. User experience data was analysed using the UEQ Data Analysis Tool and Framework Analysis. RESULTS: A total of 216 of 659 eligible students completed all sections of the e-Learning course. Participant mean age was 23.52 years, with a slight female predominance (55.3%). Across all participants, an increase in median pre- and post-test scores occurred, from 40 to 60 (Z = 11.3, p<0.001, effect size = 1.3), suggestive of increased knowledge acquisition relating to pain management. Participants suggested e-Learning is a valuable approach to delivering pain education alongside identifying factors to address in future iterations. CONCLUSION: e-Learning approaches to pain management education can enhance traditional learning methods and may increase students' knowledge. Future iterations of e-Learning approaches will need to consider facilitating the download of data and content for the platform to increase user uptake and engagement. The platform was piloted as an optional adjunct to existing curricula. Future efforts to advocate and support integration of e-Learning for pain education should be two-fold; both to include pain education in the curricula of medical colleges across Nigeria and the use of e-Learning approaches to enhance teaching where feasible.

Using the theoretical domains framework to explore reasons for missed opportunities for vaccination among children in Kano, Nigeria: a qualitative study in the pre-implementation phase of a collaborative quality improvement project.

Background: Missed opportunities for vaccination (MOV) have been identified as an important contributor to low childhood immunization coverage. In this study, we explore the reasons for MOV from the perspective of caregivers of children aged 0-23 months attending primary health care (PHC) facilities in Nassarawa Local Government Area (LGA) of Kano State, Nigeria. This was to inform the implementation of a quality improvement program to reduce MOV. Methodology: An exploratory qualitative research was conducted using focus group discussions (FGD) with caregivers of children aged 0-23 months that visited PHC facilities. The study was conducted in three purposively selected PHC facilities in Nassarawa, Kano. The caregivers were purposively selected from the three PHC facilities and were homogenous in terms of their place of residence. Each FGD was conducted face-to-face in a private room within the health facility. During the discussion, participants maintained a circular sitting arrangement. The FGD were audio-recorded, transcribed verbatim, and analyzed using template analysis approach through the lens of the theoretical domains framework (TDF) and the capability, opportunity, motivation - behavior (COM-B) model. The researchers that conducted this study are epidemiologists and implementation scientists with experience in immunization programs. They are multilingual, and some are fluent in both English and Hausa language. Although four of them are medical doctors, however, they do not have any affiliations or provide health services in any of the PHC facilities where this study was conducted. Result: Five FGD with 30 caregivers was conducted. The caregivers were aged between 19 and 32 years and lived within the LGA. Based on their lived experiences, several factors that are responsible for MOV were identified and categorized into three constructs based on the COM-B model. Capability encompassed caregiver's inadequate knowledge of the vaccines that children need. The opportunity included contextual factors such as non-screening of home-based records, health worker's refusal to offer immunization services, and husband's refusal due to socio-cultural beliefs. Finally, motivation included fear of the side effects of vaccination. Conclusion: This study identified a useful framework that aided deeper insights into caregiver-related factors responsible for MOV in Nassarawa, Kano. Some of the findings from this study can be used to inform change ideas in a quality improvement program and should be explored.

Implementation and evaluation of a collaborative quality improvement program to improve immunization rate and reduce missed opportunities for vaccination in primary health-care facilities: a time series study in Kano, Nigeria.

Background: The authors aimed to implement a quality improvement (QI) collaborative in primary health care (PHC) facilities in Nassarawa Local Government Area of Kano, Nigeria, to reduce missed opportunities for vaccination (MOV) among children aged 0-23 months. Research design and methods: Plausibility evaluation design was used in this study. Frontline health workers from five purposively selected PHC facilities used divergent-convergent thinking to select change ideas. Change ideas were implemented in two plan-do-study-act cycles that were 4 weeks apart. Statistical process control using P-chart was used to plot the outcomes over time. Upper and lower control limits were calculated for each p-chart. Results: In the facilities that implemented the QI program, the average percentage of MOV in the pre-implementation period was 31.7% with an upper control limit (UCL) of 44.5% and lower control limit (LCL) of 18.9%. After commencing QI implementation, data points stabilized as all points were within the control limits. Improvement was more evident in PHC 1 and 5. Conclusions: The findings from this study suggest that frontline health workers are capable of tailoring change ideas to their local context to generate context-specific change ideas. It also showed that QI can be used to attain process control in the occurrence of MOV.

A multilevel analysis of the determinants of missed opportunities for vaccination among children attending primary healthcare facilities in Kano, Nigeria: Findings from the pre-implementation phase of a collaborative quality improvement programme.

BACKGROUND: We aimed to determine the factors that are responsible for missed opportunities for vaccination (MOV) among children aged 0-23 months attending primary health care (PHC) facilities in Nassarawa, Kano State, Nigeria. METHODS: This cross-sectional study was conducted in the pre-implementation phase of a quality improvement programme. One-stage cluster sampling technique was employed. Data were collected from caregivers of children aged 0-23 months in ten randomly selected PHC facilities in Nassarawa Local Government Area of Kano State. Semi-structured, interviewer administered questionnaires were used. Frequencies and percentages were used to summarize the data. Multilevel logistic regression model with fixed effect and random effect component was fitted to obtain measures of association and variation respectively. RESULTS: Caregivers of 675 children responded. Among these children, the prevalence of MOV (for at least one antigen) was 36.15%. MOV (for individual antigens) was highest for inactivated polio vaccine followed by measles vaccine. The random effect model yielded an intraclass correlation coefficient of 9.60% for the empty model. The fixed effect model revealed that MOV was more likely among children that were accompanying a caregiver to the health facility (OR = 2.86, 95%CrI: 1.28 to 5.80) compared to those that were visiting the health facility for medical consultation. Failure to receive vaccination on the day of health facility visit (OR = 2.32, 95%CrI: 1.12 to 4.12) and visiting a clinic with three or more vaccinators (OR = 12.91, 95%CrI: 4.82 to 27.14) increased the likelihood of MOV. CONCLUSION: The study identified important local factors that are responsible for MOV which can be addressed in the QI programme.

Application of quality improvement approaches in health-care settings to reduce missed opportunities for childhood vaccination: a scoping review.

Missed opportunities for vaccination (MOV) is a poor reflection of the quality of care for children attending health facilities. It also contributes to a reduction in overall immunization coverage. Although there is a growing interest in the use of quality improvement (QI) in complex health systems to improve health outcomes, the degree to which this approach has been used to address MOV is poorly understood. We conducted a scoping review using Arksey and O'Malley's framework to investigate the extent to which QI has been used in health facilities to reduce MOV. The review followed five stages as follows: (1) identifying the research question; (2) identifying the relevant studies; (3) selecting the studies; (4) charting data; and (5) collating, summarizing, and reporting results. The search strategy included electronic databases and gray literature. A total of 12 literatures on QI projects focused on addressing MOV were identified. Eleven were published manuscripts, and one was a conference presentation. All the QI projects published were conducted in the United States and majority were between 2014 and 2018. In these projects, 45 change ideas targeting providers, clients, and health system were used. This study generated important evidence on the use of QI in health facilities to reduce MOV. In addition, the result suggests that there is a growing interest in the use of this approach to address MOV in recent years. However, no literature was found in low- and middle-income countries especially sub-Saharan Africa.

Prevalence and dynamics of missed opportunities for vaccination among children in Africa: applying systems thinking in a systematic review and meta-analysis of observational studies.

OBJECTIVE: To estimate the prevalence of missed opportunities for vaccination (MOV) among children aged 0-23 months attending health-care facilities in Africa and explore the factors responsible for MOV using systems thinking. RESEARCH DESIGN AND METHODS: We conducted a systematic review and meta-analysis of studies reporting the proportion MOVs. Five electronic databases were searched. A random effects model was fitted to obtain pooled estimates of MOV and a causal loop diagram (CLD) was constructed to explore the dynamics of the causes of MOV. MOV was defined as any contact with health services in Africa, by an unvaccinated or under-vaccinated child, aged 0-23 months, who is eligible for vaccination and free of any contraindication, which does not result in vaccination. RESULTS: Four hundred and twenty-one publications were found, of which 20 studies from 14 countries were included. The pooled prevalence of MOV was estimated to be 27.26% (95%CI: 18.80-36.62). A CLD with seven reinforcing and two balancing loops were constructed. CONCLUSION: Our findings suggest that about one in every four children under the age of two years who visited health facilities in 14 African countries missed the vaccination they were eligible to receive. To enable continent-wide estimates, more MOV assessments are required.

The role of intervention mapping in designing disease prevention interventions: A systematic review of the literature.

OBJECTIVE: To assess the role of Intervention Mapping (IM) in designing disease prevention interventions worldwide. METHODS: Systematic search and review of the relevant literature-peer-reviewed and grey-was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. FINDINGS: Only five of the twenty two included studies reviewed were RCTs that compared intervention using IM protocol with placebo intervention, and provided the outcomes in terms of percentage increase in the uptake of disease-prevention programmes, and only one of the five studies provided an effect measure in the form of relative risk (RR = 1.59, 95% CI = 1.08-2.34, p = 0.02). Of the five RCTs, three were rated as strong evidences, one as a medium evidence and one as a weak evidence, and they all reported statistically significant difference between the two study groups, with disease prevention interventions that have used the intervention mapping approach generally reported significant increases in the uptake of disease-prevention interventions, ranging from 9% to 28.5% (0.0001 ≤ p ≤ 0.02), On the other hand, all the 22 studies have successfully identified the determinants of the uptake of disease prevention interventions that is essential to the success of disease prevention programmes. CONCLUSION: Intervention Mapping has been successfully used to plan, implement and evaluate interventions that showed significant increase in uptake of disease prevention programmes. This study has provided a good understanding of the role of intervention mapping in designing disease prevention interventions, and a good foundation upon which subsequent reviews can be guided.

Coverage and determinants of childhood immunization in Nigeria: A systematic review and meta-analysis.

INTRODUCTION: The proportion of fully immunized children in Nigeria is reportedly low. There are concerns over national immunization data quality, with this possibly limiting country-wide response. We reviewed publicly available evidence on routine immunization across Nigeria to estimate national and zonal coverage of childhood immunization and associated determinants. METHODS: A systematic search of Medline, EMBASE, Global Health and African Journals Online (AJOL) was conducted. We included population-based studies on childhood immunization in Nigeria. A random effects meta-analysis was conducted on extracted crude rates to arrive at national and zonal pooled estimates for the country. RESULTS: Our search returned 646 hits. 21 studies covering 25 sites and 26,960 children were selected. The estimated proportion of fully immunized children in Nigeria was 34.4% (95% confidence interval [CI]: 27.0-41.9), with South-south zone having the highest at 51.5% (95% CI: 20.5-82.6), and North-west the lowest at 9.5% (95% CI: 4.6-14.4). Mother's social engagements (OR=4.0, 95% CI: 1.9-8.1) and vaccines unavailability (OR=3.9, 95% CI: 1.2-12.3) were mostly reported for low coverage. Other leading determinants were vaccine safety concerns (OR=3.0, 95% CI: 0.9-9.4), mother's low education (OR=2.5, 95% CI: 1.8-3.6) and poor information (OR=2.0, 95% CI: 0.8-4.7). CONCLUSION: Our study suggests a low coverage of childhood immunization in Nigeria. Due to the paucity of data in the Northern states, we are still uncertain of the quality of evidence presented. It is hoped that this study will prompt the needed research, public health and policy changes toward increased evenly-spread coverage of childhood immunization in the country.