Table 2.

Overview on data at the individual patient level: constructs and operationalizations

	Constructs/concepts	Score/instrument
Socio-demographic characteristics	age, gender
	living situation, presence of informal caregiver(s), marital status
	nationality
	educational and professional level, employment
	subjective social status	MacArthur-Scale [23]
General medical characteristics	height, weight, waist circumference
	history of smoking, current smoking
	comorbidity	according to SAPS III [32]
	history of psychiatric disorders
Medical characteristics relating to ARDS and its treatment	cause and severity of ARDS	according to the “Berlin-Definition” [15]
	prognostic scores at ICU admission	SAPS II [31], SAPS III [32]
	organ dysfunction/failure	SOFA [33]
	blood gas analysis
	ventilation parameters
	presence of delirium	CAM-ICU, RASS [41]
	treatment with supportive care measures: ECMO, NO-inhalation, prone-positioning, muscle relaxant medication, tracheotomy
	complications
	length of ICU stay
Characteristics of health institution use	length of hospital stay before referral to specialized centre, duration of inter-hospital transport, length and type of rehabilitative measures
	outpatient health-service use
Psycho-social characteristics	prevalence of psychopathological syndromes: major depressive syndrome, panic syndrome, PTSD, alcohol abuse	PHQ [26], PTSS-14 [28, 29]
	disability	Barthel-Index of Activities of Daily Living [42, 43]
	social support	F-SOZU [30]
	healthrelated quality of life	SF-12 [21]
	return to work

Notes: bold: moderators and main outcomes