Maxwell Barffour

Technical skills improve after practice on virtual‐reality temporal bone simulator

To assess whether practice on a virtual‐reality (VR) temporal bone simulator improves acquisition of technical skills in mastoid surgery.

Evidence-Based Road Safety Practice in India: Assessment of the Adequacy of Publicly Available Data in Meeting Requirements for Comprehensive Road Safety Data Systems

Objective: To assess the availability and coverage of publicly available road safety data at the national and state levels in India. Methods: We reviewed the 2 publicly accessible data sources in India for the availability of data related to traffic injuries and deaths: (1) the National Crime Records Bureau (NCRB) and (2) the Ministry of Road Transport and Highways (MORTH). Using the World Health Organization (WHO) manual for the comprehensive assessment of road safety data, we developed a checklist of indicators required for comprehensive road safety assessment. These indicators were then used to assess the availability of road safety data in India using the NCRB and MORTH data. We assessed the availability of data on outcomes and exposures indicators (i.e., number of crashes, injuries, deaths, timing of deaths, gender and age distribution of injuries and deaths), safety performance indicators (i.e., with reference to select risk factors of speeding, alcohol, and helmet use), and cost indicators (i.e., medical costs, material costs, intervention costs, productivity costs, time costs, and losses to quality of life). Results: Information on outcome indicators was the most comprehensive in terms of availability. Both NCRB and MORTH databases had data for most of the need areas specified by the WHO under outcomes and exposure indicators. Regarding outcome and exposure indicators, data were available for 81 and 91 percent of specified need areas at the national level from NCRB and MORTH databases, respectively. At the state level, data on outcome and exposure indicators were available for only 54 percent of need areas from either of the 2 sources. There were no data on safety performance indicators in the NCRB database. From the MORTH database, data availability on safety performance indicators was 60 percent at both national and state levels. Data availability on costs and process indicators was found to be below 20 percent at the national and state levels. Conclusion: Overall, there is an urgent need to improve the publicly available road safety data in India. This will enhance monitoring of the burden of traffic injuries and deaths, enable sound interpretation of national road safety data, and allow the formulation effective road safety policies.

Short-Term Daily Consumption of Provitamin A Carotenoid–Biofortified Maize Has Limited Impact on Breast Milk Retinol Concentrations in Zambian Women Enrolled in a Randomized Controlled Feeding Trial

BACKGROUND Provitamin A carotenoid-biofortified maize is a conventionally bred staple crop designed to help prevent vitamin A deficiency. Lactating women are a potential target group, because regularly eating biofortified maize may increase vitamin A in breast milk-a critical source of vitamin A for breastfeeding infants. OBJECTIVE We assessed whether daily consumption of biofortified orange maize would increase the retinol concentration in the breast milk of Zambian women. METHODS Lactating women (n = 149) were randomly assigned to receive orange maize delivering 600 μg retinol equivalents (REs)/d as carotenoid plus placebo (OM), low-carotenoid white maize plus 600 μg REs/d as retinyl palmitate (VA), or white maize plus placebo (WM). Boiled maize (287 g dry weight/d) was served as 2 meals/d, 6 d/wk for 3 wk. We measured initial and final breast milk plasma retinol and β-carotene concentrations, and plasma inflammatory protein concentrations. RESULTS Groups were comparable at enrollment, with an overall geometric mean milk retinol concentration of 0.95 μmol/L (95% CI: 0.86, 1.05 μmol/L); 56% of samples had milk retinol <1.05 μmol/L. Median capsule and maize intake was 97% and 258 g dry weight/d, respectively. Final milk β-carotene did not vary across groups (P = 0.76). Geometric mean (95% CI) milk retinol concentration tended to be higher in the OM [1.15 μmol/L (0.96, 1.39 μmol/L)] and VA [1.17 μmol/L (0.99, 1.38 μmol/L)] groups than in the WM group [0.91 μmol/L (0.72, 1.14 μmol/L); P = 0.13], and the proportion of women with milk retinol <1.05 μmol/L was 52.1%, 42.9%, and 36.7% in the WM, OM, and VA groups, respectively (P-trend = 0.16). CONCLUSIONS Daily biofortified maize consumption did not increase mean milk retinol concentration in lactating Zambian women; however, there was a plausible downward trend in the risk of low milk retinol across intervention groups. This trial was registered at clinicaltrials.gov as NCT01922713.

Malaria exacerbates inflammation-associated elevation in ferritin and soluble transferrin receptor with only modest effects on iron deficiency and iron deficiency anaemia among rural Zambian children

In 4‐ to 8‐year‐old Zambian children (n = 744), we evaluated the effects of adjusting for inflammation (α1‐acid glycoprotein >1 g/l), with or without additional adjustment for malaria, on prevalence estimates of iron deficiency (ID) and iron deficiency anaemia (IDA) during low malaria (LowM) and high malaria (HighM) transmission seasons.

Comparison of haemoglobin assessments by HemoCue and two automated haematology analysers in young Laotian children

Background Haemoglobin (Hb) assessment by Hemocue is used widely for anaemia screening in both adults and children. However, few studies have compared the diagnostic accuracy of Hemocue with an automated haematology analyser in young children. Aim To compare Hb concentrations by Hemocue Hb301 and two automated haematology analysers in young children in rural communities of Lao PDR. Methods Capillary blood was collected from 6-month-old to 23-month-old children (n=1487) for determination of Hb concentration by Hemocue Hb301. On the same day, venous blood was collected for complete blood count using one of two haematology analysers (XT-1800i, Sysmex, and BC-3000Plus, Mindray Medical International). In a subsample of children (n=129), venous Hb was also measured by HemoCue Hb301. Agreement between the two methods was estimated using Bland-Altman plots. Results Mean capillary Hb by Hemocue was significantly higher than mean venous Hb by haematology analysers combined (108.4±10.3 g/L vs 102.3±13.1 g/L; P<0.001), resulting in a significantly lower anaemia prevalence (Hb <110 g/L) by Hemocue (53.7% vs 73.9%; P<0.001). The Bland-Altman assessment of agreement showed a bias of 6.1 g/L and limits of agreement were −11.5 g/L to 23.7 g/L. Mean venous Hb concentration by Hemocue Hb301 (113.6±14.0 g/L) was significantly higher than mean capillary Hb concentration by Hemocue Hb301 (110.0±10.7; P=0.03 g/L), which in turn was significantly higher than mean venous Hb concentration by the Mindray BC-3000Plus (102.3±17.4 g/L). Conclusion Capillary and venous Hb concentrations assessed by Hemocue Hb301 showed poor agreement compared with venous Hb by automated haematology analysers, resulting in significantly different anaemia prevalences.

Impact of biofortified maize consumption on serum carotenoid concentrations in Zambian children

Biofortified maize, designed as an intervention strategy to prevent vitamin A deficiency, can provide upwards of 15 μg β-carotene per g dry weight. Some varieties also have elevated concentrations of other carotenoids. We conducted a cluster randomized, controlled feeding trial in rural Zambia to test the impact of daily consumption of biofortified maize over a 6-month period on vitamin A status. Serum concentrations of retinol and carotenoids were assessed by high-performance liquid chromatography. Data on circulating carotenoids by intervention group in 679 children are reported here. As previously shown, consumption of this β-carotene-rich maize significantly improved serum β-carotene concentrations (0.273 vs. 0.147 μmol/L, p < 0.001, in this subset of children). Here we show significant increases in α-carotene, β-cryptoxanthin, and zeaxanthin (p < 0.001). There was no impact on lutein or lycopene concentrations. Consumption of biofortified maize can have broader implications beyond the control of vitamin A deficiency (Trial registration: NCT01695148).

High Iron Stores in the Low Malaria Season Increase Malaria Risk in the High Transmission Season in a Prospective Cohort of Rural Zambian Children

Background: Higher iron stores, defined by serum ferritin (SF) concentration, may increase malaria risk.Objective: We evaluated the association between SF assessed during low malaria season and the risk of malaria during high malaria season, controlling for inflammation.Methods: Data for this prospective study were collected from children aged 4-8 y (n = 745) participating in a biofortified maize efficacy trial in rural Zambia. All malaria cases were treated at baseline (September 2012). We used baseline SF and malaria status indicated by positive microscopy at endline (March 2013) to define exposure and outcome, respectively. Iron status was defined as deficient (corrected or uncorrected SF <12 or <15 μg/L, depending on age <5 or ≥5 y, respectively), moderate (<75 μg/L, excluding deficient), or high (≥75 μg/L). We used a modified Poisson regression to model the risk of malaria in the high transmission seasons (endline) as a function of iron status assessed in the low malaria seasons (baseline).Results: We observed an age-dependent, positive dose-response association between ferritin in the low malaria season and malaria incidence during the high malaria season in younger children. In children aged <6 y (but not older children), we observed a relative increase in malaria risk in the moderate iron status [incidence rate ratio (IRR) with SF: 1.56; 95% CI: 0.64, 3.86; IRR with inflammation-corrected SF: 1.92; 95% CI: 0.75, 4.93] and high iron status (IRR with SF: 2.66; 95% CI: 1.10, 6.43; or IRR with corrected SF: 2.93; 95% CI: 1.17, 7.33) categories compared with the deficient iron status category. The relative increase in malaria risk for children with high iron status was statistically significant only among those with a concurrently normal serum soluble transferrin receptor concentration (<8.3 mg/L; IRR: 1.97; 95% CI: 1.20, 7.37).Conclusions: Iron adequacy in 4- to 8-y-old children in rural Zambia was associated with increased malaria risk. Our findings underscore the need to integrate iron interventions with malaria control programs. This trial was registered at clinicaltrials.gov as NCT01695148.

Comparability of Inflammation-Adjusted Vitamin A Deficiency Estimates and Variance in Retinol Explained by C-Reactive Protein and α1-Acid Glycoprotein during Low and High Malaria Transmission Seasons in Rural Zambian Children

Inflammation-induced hyporetinolemia (IIH), a reduction in serum retinol (SR) during inflammation, may bias population estimates of vitamin A deficiency (VAD). The optimal adjustment for IIH depends on the type and extent of inflammation. In rural Zambian children (4-8 years, N = 886), we compared three models for defining inflammation: α-1-acid glycoprotein (AGP) only (inflammation present if > 1 g/L or normal if otherwise), C-reactive protein (CRP) only (moderate inflammation, 5-15 mg/L; high inflammation, > 15 mg/L; or normal if otherwise) and a combined model using both AGP and CRP to delineate stages of infectious episode. Models were compared with respect to 1) the variance in SR explained and 2) comparability of inflammation-adjusted VAD estimated in low and high malaria seasons. Linear regression was used to estimate the variance in SR explained by each model and in estimating the adjustment factors used in generating adjusted VAD (retinol < 0.7 μmol/L). The variance in SR explained were 2% (AGP-only), 11% (CRP-only), and 11% (AGP-CRP) in the low malaria season; and 2% (AGP-only), 15% (CRP-only), and 12% (AGP-CRP) in the high malaria season. Adjusted VAD estimates in the low and high malaria seasons differed significantly for the AGP (8.2 versus 13.1%) and combined (5.5 versus 9.1%) models but not the CRP-only model (6.1 versus 6.3%). In the multivariate regression, a decline in SR was observed with rising CRP (but not AGP), in both malaria seasons (slope = -0.06; P < 0.001). In this malaria endemic setting, CRP alone, as opposed to CRP and AGP, emerged as the most appropriate model for quantifying IIH.