Comparison of the effects of different growth standards on infants in Urban Shanghai: a cluster-randomized controlled trial

Validation of growth standards and growth references: A review of literature

The World Health Organization (WHO) growth standards provide the most recognized and widely accepted way of assessing child growth. To ensure its applicability, accuracy, and reliability, studies have validated WHO growth standards against local populations and other internationally recognized growth references. We reviewed outcomes of evaluations done on WHO growth standards and assess the appropriateness of using these growth standards on a global level. We undertook a systematic quantitative review of studies published from 2011 to 2020 from multiple databases. Studies were included if they considered children aged 59 months and below and reported on validation of growth standards. There was an agreement in studies that validated WHO growth standards against international growth references of its superiority in identifying stunted, overweight, and obese children. However, they were less likely to identify underweight children. None of the studies reviewed reported similar growth trajectories to WHO standards in all indicators considered. Regional differences in child growth were observed in comparison to WHO growth standards. Adoption of regional-specific standards increases the sensitivity of identifying children with adverse nutrition outcomes.

Cognitive Advantage of Bilingualism Over Monolingualism in Older Adults: A Meta-Analysis

OBJECTIVES

This study aimed to explore whether bilingual older adults had a cognitive advantage over their monolingual counterparts, and validate the influence of cognition-related (participants' cognitive condition, the cognitive domain assessed), and bilingualism-related factors (second language proficiency, frequency of use, acquisition time, and immigration status of participants)on the cognitive advantage of bilingualism.

METHODS

Through a systematic search of nine databases (Web of Science, PubMed, Elsevier Science Direct, Cochrane Library, Embase, PsycINFO, CNKI, VIP and Wanfang) from the inception to April 2021, observational studies with bilingual and monolingual older adults as participants and cognitive function scores as outcome measures were included. Two reviewers independently completed the selection and methodological quality assessment of studies using the JBI cross-sectional study quality evaluation tool and used a pre-designed table for data extraction and sorting.

RESULTS

Fourteen studies with 51 tasks were included, involving 3737 participants (bilingual group: 1695, monolingual group: 2042). The overall results of the meta-analysis showed that bilingualism had a small cognitive advantage over monolingualism in older adults [SMD=0.23, 95%CI (0.07, 0.38), P=0.004]. In addition, the subgroup analyses indicated that factors such as participants' cognitive condition, the cognitive domain assessed, second language proficiency, acquisition time, and immigration status of participants impacted the cognitive advantage of bilingualism in older adults.

CONCLUSION

Bilingualism had a mild cognitive advantage over monolingualism in older adults, which was more prominent in older adults with mild cognitive impairment than in cognitively healthy ones, more evident in global cognitive function and inhibitory control than in other individual cognitive domains, and might be influenced by the proficiency and acquisition time of second language as well as the immigration status of older adults.