. Author manuscript; available in PMC: 2017 Dec 1.

Published in final edited form as: Crit Care Med. 2016 Dec;44(12):e1155–e1164. doi: 10.1097/CCM.0000000000001949

Table 2.

Construct validity: Cross-sectional relationship of FSS-ICU with other outcome measures across publications and assessment time points

		Construct and Convergent Validity (Pearson correlation)								Discriminant Validity (Biserial correlation^a)
Time Point by Publication	N	IADL	ADL	MMT	Hand grip % predictted	Hand grip strength (kg)	ICU Mobility scale^b	ICU LOS	Hospital LOS	BMI (kg/m²)	Contin- ence item from ADL	Hemo- dialysis status	Need for home oxygen	Steroid use^c	Insulin use^c
Pre-hospitalization
USA - Kho	32	0.48^*	0.73^*							-0.04	0.09
USA - Needham	46-50	0.57^*	0.80^*							<0.01	0.01
Combined	78-82	0.55^*	0.80^*							-0.03	0.03
ICU awakening/admission^d
USA - Kho	20-29		0.48^*	0.81^*	0.44^*	0.41	0.46^*			-0.01	0.50^*
USA - Needham	43-52			0.72^*						0.16
Australia	19-66			0.62^*	0.30	0.30				-0.17
Brazil – da Silva	99			0.38^*
Brazil – Neto	561			0.32^*
Combined	20-802		0.39^*	0.44^*	0.40^*	0.37^*	0.46^*			-0.01	0.50^*
ICU discharge
USA - Kho	12-27		0.70^*	0.70^*	0.43^*	0.50^*	0.62^*	0.03		0.05	0.70^*	0.06		-0.20	0.33
USA - Needham	39-47			0.76^*				-0.18		0.31^*		-0.26		0.30	0.05
Australia^e	20-66			0.68^*	0.62^*	0.70^*	0.69^*	-0.24		-0.21
Brazil – da Silva	99						0.95^*	-0.20^*
Brazil – Neto	561			0.64^*				-0.27^*
Combined	27-800		0.70^*	0.60^*	0.50^*	0.59^*	0.86^*	-0.25^*		0.05	0.70^*	-0.20		0.19	0.11
Hospital discharge
USA - Kho	12-28		0.86^*	0.80^*	0.46^*	0.51^*			-0.17	-0.12	0.78^*	0.30	-0.12	-0.15	0.33
USA - Needham	15-44		0.81^*	0.80^*					-0.34^*	0.11	0.29	0.14	0.22	-0.12	-0.24
Australia data	8-19			0.39	0.51^*	0.61^*			-0.46^*	-0.37
Combined	31-91		0.80^*	0.80^*	0.43^*	0.49^*			-0.26^*	-0.05	0.42^*	0.38^*	0.05	-0.16	-0.06

Abbreviations: FSS-ICU: functional status score for the intensive care unit; IADL: instrumental activities of daily living; ADL: activities of daily living; MMT: manual muscle testing; LOS: length of stay; BMI: body mass index.

p <0.05.

Biserial correlations evaluate a correlation when one variable is dichotomous, and were used to evaluate correlation with continence, hemodialysis, home oxygen, steroids and insulin use.

This Hodgson ordinal ICU mobility scale evaluates patients’ highest mobility level, during physical therapy assessment in the ICU, and ranges from 0 (lying in bed) to 10 (walking independently without a gait aid).

Represents any use of this medication on hospital ward (for the ICU discharge time point) and upon hospital discharge (for hospital discharge time point).

ICU awakening was defined using the De Jonghe criteria in USA-Kho and Australia studies; in the USA-Needham, study, it was defined based on Richmond Agitation Sedation Scale and ability to follow instructions to perform the assessment.

A total of 20 patients had hand grip data and 41 had ICU mobility scale data.