Table 5.

Key Research and Knowledge Gaps for Clinical Nutrition in Patients During Pre-, Acute, and Chronic/Post- Stages of COVID-19.^a

COVID-19 stage	Research gaps	Knowledge gaps
Pre– and chronic/post–COVID-19	PICO-T 1–11 (all)	PICO-T 1,2, 11, 16
Pre–COVID-19	Food insecurity/social infrastructure Malnutrition	None
	Dietary management and cardiometabolic risk
	Transcultural Factors
	RCTs
Acute COVID-19	PICO-T 19-41 (All)	PICO-T 20, 21, 24, 27, 31, 33, 37
	Obesity in ICU, community/outpatient/academic settings	None
	Pediatrics
	Nutrition assessment (eg, prehospitalization weight loss)
	Refeeding syndrome
	Nutrition support, especially with glycemic control
	Hospital infrastructure (eg, training, shortages, and protocols)
	RCTs
Chronic/Post-COVID-19	PICO-T 42–56 (All)	PICO-T 52, 53
	Nutrition risk assessment, outpatient	Home EN and PN support
	Weight management to improve recovery	Long-term nutrition effects
	Protein-energy targets to decrease complications
	Impact of RDN counseling
	RCTs
Aggregated COVID-19 stages	Homecare, nursing homes, and obstetrics (outpatient/ICU)	Homecare and nursing homes
	Academic settings for obesity, malnutrition, obstetrics, low SES, and ethnic minorities

COVID-19, coronavirus disease 2019; ICU, intensive care unit; PICO-T, Population, Intervention, Comparator, Outcome, and Time; RDN, registered dietitian nutritionist; RCT, randomized controlled trial; SES, socioeconomic status.

^aKey gaps are those interpreted by the task force members as critical for nutrition research and systematic reviews. Heat map of gaps in the nutrition topics vs study design in Figure 3A correspond to specific PICO-T questions listed in Table 4. Gaps discovered with more detailed analysis of data sets by the primary writer teams are presented in italics. Heat maps of gaps in settings vs populations in Figure 3B and 3C correspond to specific cross-tabulations, do not map to specific PICO-T questions, and are not specific to any given COVID-19 stage (presented as aggregated COVID-19 stages).