Table 3.

Harmonization Level 3 Protocol

#	Domain	Format	Completion time (min.)	Mode of administration
1	Demographic inventory Use COVID-19 Neuro Network CRF Adapt/include socio-economic and cultural factors	CRF Questionnaire	10–30	Self Always consider informant In-person Telehealth may be used* Use medical records Use information from treating doctors
2	Medical history questionnaire includes CNS symptoms Use COVID-19 Neuro Network CRF and added scales Supplement with history taking	CRF Questionnaire	10–60
3	Neurocognitive testing	Standard neuropsychological test battery Combine with HL1 & HL2 as appropriate	60–90	In-person Part of the assessment may be adapted for telehealth but guidance from test developers is strongly recommended (see also dedicated section on telehealth)
4	Smell and taste questionnaire	Questionnaire	5–10	In-person Telehealth may be used* Self Can be aided by informant Email or secure mailing of questionnaires may be used*
5	Cognitive symptoms questionnaire Supplement with history taking	Questionnaire	5–20
6	Mental and Psychosocial health Supplement with history taking to target key information and select more questionnaires.	Questionnaire	5–30
7	Objective olfaction/taste testing	Standard Test: 4 options	5–20	In-person Can be adapted for telehealth for some tests
8	Literacy, quality of education & premorbid ability	Standard Test	5–10	In-person Can be adapted for telehealth for some tests
9	ADL Supplement with history taking to target key information and select more questionnaires.	Questionnaire +Informant	5–30	In-person Telehealth may be used* Email or secure mailing of questionnaires may be used* Self + Should be aided by informant
10	Performance Validity	Standard Test	3–10	In-person or telehealth*

NB: the protocol material is available in Supplementary Material 2 and 3

^*Some information may be filled out by participants/patients and their informants at their convenience within 3 days of neuropsychological exam.