Table 1. Summary of study visits, domains and assessment instruments^*.

Visit	Step	Domain	Instrument	Purpose	Timing
V1	S1	Sociodemographic	Survey form	Baseline characterisation	Baseline
		Medical history	Medical history form	Identify risk/modifying factors
		Quality of life	QoL instrument	Assess functional impact
		Health behaviours	Behavioural questionnaire	Lifestyle-related recovery factors
	S2	Blood biomarkers	Clinical lab panel	General physiological status
		Immune profiling	Research lab panel	Immune system evaluation
	S3	Cognitive function	WAIS-IV	Cognitive sequelae detection
		Mental health	Standardised scales	Psychological impact
		Sleep quality	Sleep Quality Index	Evaluate sleep-related symptoms
V2	S1	Physical performance	FAS, InBody, dynamic handgrip.	Functional impact assessment	Follow-up
		PEM	DePaul PEM section	Evaluate PEM response
		Respiratory function	Pulmonary tools	Pulmonary sequelae
V3	S1	Gait and posture	3D photogrammetry	Motor system evaluation
	S2	Integrated assessment	All instruments used	Diagnostic confirmation of post-COVID	Final visit

^*See online supplemental table 1 for full variable details and measurement methods.

FAS, Fatigue Assessment Scale; InBody, body composition analyser; PEM, post-exertional malaise; QoL, quality of life; WAIS-IV, Wechsler Adult Intelligence Scale (fourth edition).