Clinical use of metal and plastic calipers for nutritional assessment of patients under long-term enteral feeding through endoscopic gastrostomy

Background: Endoscopic gastrostomy (PEG) fed patients, including those with neurologic disorders (ND) or head and neck cancer (HNC) present high malnutrition risk and speech difficulties. Teams taking care of these patients need to rely on anthropometric data. Skinfold thickness (TSF) is used to assess nutritional status, but the use of heavy, large and expensive metal calipers may become a limitation. This study aimed to compare and correlate TSF measurements using a metal caliper and a plastic caliper in PEG fed patients. Methods: Prospective observational study on adult PEG fed patients. TSF was measured using plastic Ross and Lange metal calipers. Paired measurements were compared and correlated. Results: Fifty-one patients, 37 men (72.5%), 14 women (27.5%): 28 (54.9%) ND patients; 23 (45.1%) with HNC. In total, 94 TSF measurements were performed using both plastic and metal calipers. Significant association was found between TSF measurements with the two equipments (rs = 0.94; p < 0.001). High correlation was observed between TSF measurements using both calipers for both genders (men: rs = 0.93; p < 0.001; women: rs = 0.96; p < 0.001), age (< 65 years: rs = 0.98; p < 0.001; ≥ 65 years: rs = 0.88; p < 0.001), underlying condition (ND: rs = 0.91; p < 0.001; HNC: rs = 0.95; p < 0.001) and time of TSF evaluation (before PEG: rs = 0.95; p < 0,001; after PEG: rs = 0.92; p < 0.001). Conclusions: TSF measurements obtained with small, light and cheap plastic Ross caliper were equivalent to those obtained with larger, heavier and more expensive metal caliper. For everyday clinical practice, plastic calipers may be suitable for teams taking care of PEG fed patients in hospital wards, outpatient clinic and home visits.