“Average of neck circumference in Latin American adults: protocol for a systematic review and meta-analysis”

Background Because these are inexpensive and (fairly) easy to conduct, anthropometric measurements have been widely used as risk factors for many diseases (e.g., cardiovascular or cancer). Recently, there have been several reports pinpointing the association between neck circumference and obstructive sleep apnea, cardiovascular and metabolic diseases. These conditions are highly prevalent Latin American and the Caribbean (LAC), where they carry a large disease and disability burden. Neck circumference arises as a potential complement of established anthropometric measurements, namely weight, height and waist/hip circumference. However, unlike these well-known measurements, evidence about neck circumference is scarce and has not been systematically collected in LAC. Objective To summarize the average neck circumference in LAC adults; and, exploratorily, to summarize the prevalence of large neck circumference (i.e., neck/cervical obesity). Methods Systematic review and meta-analysis. We will conduct a search in OVID (MEDLINE, Embase, Global Health) and LILACS. Search terms include those related to neck circumference, along with countries in LAC. We seek observational studies with a random sample of the general population, closed populations (e.g., workers), and patients; results will be presented for each of these groups. We will screen titles and abstracts; we will study in detail the selected papers. Both phases will be conducted by two reviewers independently. We will develop an extraction form to collate: country/year of data collection, methods of data collection, average neck circumference and, if available, prevalence of large neck circumference. Data extraction will be conducted by two reviewers independently. We will use the tool proposed by Hoy et al. and the Newcastle-Ottawa scale to assess the risk of bias. Conclusions This systematic review and meta-analysis will provide the average neck circumference in LAC adults. Currently, evidence about neck circumference in LAC has not been systematically studied, appraised or summarized. This work will provide information about this novel anthropometric measurement, and spark attention about its role as a potential anthropometric indicator and health risk factor. Conflicts of interest All authors declare to have no conflicts of interest. Funding Rodrigo M Carrillo-Larco is supported by a Wellcome Trust International Training Fellowship (214185/Z/18/Z).