Evaluating Scope and Bias of Population-Level Measles Serosurveys: A Systematized Review and Bias Assessment.

BACKGROUND: Measles seroprevalence data have potential to be a useful tool for understanding transmission dynamics and for decision making efforts to strengthen immunization programs. In this study, we conducted a systematized review and bias assessment of all primary data on measles seroprevalence in low- and middle-income countries (as defined by World Bank 2021 income classifications) published from 1962 to 2021. METHODS: On 9 March 2022, we searched PubMed for all available data. We included studies containing primary data on measles seroprevalence and excluded studies if they were clinical trials or brief reports, from only health-care workers, suspected measles cases, or only vaccinated persons. We extracted all available information on measles seroprevalence, study design, and seroassay protocol. We conducted a bias assessment based on multiple categories and classified each study as having low, moderate, severe, or critical bias. This review was registered with PROSPERO (CRD42022326075). RESULTS: We identified 221 relevant studies across all World Health Organization regions, decades, and unique age ranges. The overall crude mean seroprevalence across all studies was 78.0% (SD: 19.3%), and the median seroprevalence was 84.0% (IQR: 72.8-91.7%). We classified 80 (36.2%) studies as having severe or critical overall bias. Studies from country-years with lower measles vaccine coverage or higher measles incidence had higher overall bias. CONCLUSIONS: While many studies have substantial underlying bias, many studies still provide some insights or data that could be used to inform modelling efforts to examine measles dynamics and programmatic decisions to reduce measles susceptibility.

Multilevel analysis of predictors of multiple indicators of childhood vaccination in Nigeria.

BACKGROUND: Substantial inequalities exist in childhood vaccination coverage levels. To increase vaccine uptake, factors that predict vaccination coverage in children should be identified and addressed. METHODS: Using data from the 2018 Nigeria Demographic and Health Survey and geospatial data sets, we fitted Bayesian multilevel binomial and multinomial logistic regression models to analyse independent predictors of three vaccination outcomes: receipt of the first dose of Pentavalent vaccine (containing diphtheria-tetanus-pertussis, Hemophilus influenzae type B and Hepatitis B vaccines) (PENTA1) (n = 6059) and receipt of the third dose having received the first (PENTA3/1) (n = 3937) in children aged 12-23 months, and receipt of measles vaccine (MV) (n = 11839) among children aged 12-35 months. RESULTS: Factors associated with vaccination were broadly similar for documented versus recall evidence of vaccination. Based on any evidence of vaccination, we found that health card/document ownership, receipt of vitamin A and maternal educational level were significantly associated with each outcome. Although the coverage of each vaccine dose was higher in urban than rural areas, urban residence was not significant in multivariable analyses that included travel time. Indicators relating to socio-economic status, as well as ethnic group, skilled birth attendance, lower travel time to the nearest health facility and problems seeking health care were significantly associated with both PENTA1 and MV. Maternal religion was related to PENTA1 and PENTA3/1 and maternal age related to MV and PENTA3/1; other significant variables were associated with one outcome each. Substantial residual community level variances in different strata were observed in the fitted models for each outcome. CONCLUSION: Our analysis has highlighted socio-demographic and health care access factors that affect not only beginning but completing the vaccination series in Nigeria. Other factors not measured by the DHS such as health service quality and community attitudes should also be investigated and addressed to tackle inequities in coverage.

An assessment of PCV13 vaccine coverage using a repeated cross-sectional household survey in Malawi.

Background: The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in Malawi from November 2011 using a three dose primary series at 6, 10, and 14 weeks of age to reduce Streptococcus pneumoniae-related diseases. To date, PCV13 paediatric coverage in Malawi has not been rigorously assessed.  We used household surveys to longitudinally track paediatric PCV13 coverage in rural Malawi. Methods: Samples of 60 randomly selected children (30 infants aged 6 weeks to 4 months and 30 aged 4-16 months) were sought in each of 20 village clinic catchment 'basins' of Kabudula health area, Lilongwe, Malawi between March 2012 and June 2014. Child health information was reviewed and mothers interviewed to determine each child's PCV13 dose status and vaccine timing. The survey was completed six times in 4-8 month intervals. Survey inference was used to assess PCV13 dose coverage in each basin for each age group. All 20 basins were pooled to assess area-wide vaccination coverage over time, by age in months, and adherence to the vaccination schedule. Results: We surveyed a total of 8,562 children in six surveys; 82% were in the older age group. Overall, in age-eligible children, two-dose and three-dose coverage increased from 30% to 85% and 10% to 86%, respectively, between March 2012 and June 2014.  PCV13 coverage was higher in the older age group in all surveys. Although it varied by basin, PCV13 coverage was consistently delayed: median ages at first, second and third doses were 9, 15 and 21 weeks, respectively. Conclusion: In our rural study area, PCV13 introduction did not meet the Malawi Ministry of Health one-year three-dose 90% coverage target, but after 2 years reached levels likely to reduce the prevalence of both invasive and non-invasive paediatric pneumococcal diseases. Better adherence to the PCV13 schedule may reduce pneumococcal disease in younger Malawian children.

Measuring coverage in MNCH: design, implementation, and interpretation challenges associated with tracking vaccination coverage using household surveys.

Vaccination coverage is an important public health indicator that is measured using administrative reports and/or surveys. The measurement of vaccination coverage in low- and middle-income countries using surveys is susceptible to numerous challenges. These challenges include selection bias and information bias, which cannot be solved by increasing the sample size, and the precision of the coverage estimate, which is determined by the survey sample size and sampling method. Selection bias can result from an inaccurate sampling frame or inappropriate field procedures and, since populations likely to be missed in a vaccination coverage survey are also likely to be missed by vaccination teams, most often inflates coverage estimates. Importantly, the large multi-purpose household surveys that are often used to measure vaccination coverage have invested substantial effort to reduce selection bias. Information bias occurs when a child's vaccination status is misclassified due to mistakes on his or her vaccination record, in data transcription, in the way survey questions are presented, or in the guardian's recall of vaccination for children without a written record. There has been substantial reliance on the guardian's recall in recent surveys, and, worryingly, information bias may become more likely in the future as immunization schedules become more complex and variable. Finally, some surveys assess immunity directly using serological assays. Sero-surveys are important for assessing public health risk, but currently are unable to validate coverage estimates directly. To improve vaccination coverage estimates based on surveys, we recommend that recording tools and practices should be improved and that surveys should incorporate best practices for design, implementation, and analysis.

Ohio Appalachian women's perceptions of the cost of cervical cancer screening.

BACKGROUND: Despite evidence of the importance of cervical cancer screening, screening rates in the United States remain below national prevention goals. Women in the Appalachia Ohio region have higher cervical cancer incidence and mortality rates along with lower cancer screening rates. This study explored the expectations of Appalachian Ohio women with regard to Papanicolaou (Pap) test cost and perceptions of cost as a barrier to screening. METHODS: Face-to-face interviews were conducted with 571 women who were part of a multilevel, observational community-based research program in Appalachia Ohio. Eligible women were identified through 14 participating health clinics and asked questions regarding Pap test cost and perceptions of cost as a barrier to screening. Estimates of medical costs were compared with actual costs reported by clinics. RESULTS: When asked about how much a Pap test would cost, 80% of the women reported they did not know. Among women who reportedly believed they knew the cost, 40% overestimated test cost. Women who noted cost as a barrier were twice as likely to not receive a test within screening guidelines as those who did not perceive a cost barrier. Furthermore, uninsured women were more than 8.5 times as likely to note cost as a barrier than women with private insurance. CONCLUSIONS: Although underserved women in need of cancer screening commonly report cost as a barrier, the findings of the current study suggest that women may have a very limited and often inaccurate understanding concerning Pap test cost. Providing women with this information may help reduce the impact of this barrier to screening.

Multi-informant assessment of anxiety regarding ano-genital examinations for suspected child sexual abuse (CSA).

OBJECTIVE: Given the commonly held belief that physical examinations for child sexual abuse (CSA) are very distressing, our primary objective was to evaluate anxiety during these assessments using the Multidimensional Anxiety Score for Children (MASC-10). A second objective was to compare self-reported anxiety to parental report using the MASC-10 and to medical provider's rating of emotional distress using the Genital Examination Distress Scale (GEDS). METHODS: Child/parent dyads completed the MASC-10 prior to the evaluation and were retested at the completion of the medical exam. GEDS assessment occurred during the medical exam. RESULTS: One hundred seventy-five subject dyads were enrolled and were predominantly female (77%), Caucasian (66%), accompanied by mother (90%), and receiving Medicaid (57%). A significant subgroup of children reported clinically significant levels of anxiety at the pre-examination assessment (17.1%) and post-examination assessment (15.4%). However, most subjects reported low anxiety at both pre- and post-examination assessments. Both child and parent report demonstrated less anxiety, on average, post-examination compared to pre-examination scores. Reduced anxiety was measured with a mean pre-T-score=55.8 versus mean post-T-score=53.1 (p<.001). Correlation coefficients for pre-T-scores and post-T-scores of child/parent dyad were 0.3257 (p<.0001) and 0.3403 (p<.0001). A small correlation was noted between child reported anxiety and medical provider observation using the GEDS for pre-exam (0.1904, p=.01), and post-exam (0.2090, p=.02). CONCLUSIONS: Our research indicates that the majority of children are not severely anxious during medical evaluations for CSA. In addition, the MASC-10 shows promise as an instrument to assess anxiety from the ano-genital examination in CSA because it could be quickly completed by most patients and their parents, indicated a wide range of anxiety levels, and demonstrated some sensitivity to change. While parent report may identify some child anxiety, parent and provider report should not be substitutes for the self-report of children's anxiety during this medical evaluation. PRACTICE IMPLICATIONS: A practical, quick, validated measure of anxiety can be used in the setting of CSA evaluations to identify anxiety in this population.