The association between multi-disciplinary staffing levels and mortality in acute hospitals: a systematic review

Table 3 Risk of bias assessment

Study	Design	Setting	Eligible population	Selected participants	Outcome measures reliable	Outcome measures complete	Sufficient powered	Appropriate confounding	Appropriate methods	Precision of association	Internal validity	External validity
Bjerregard et al., 2020	−	+	+ +	+ +	+ +	+ +	+	+ +	+ +	+	+	+ +
Bond et al., 1999	−	+	+ +	+ +	+ +	+ +	+ +	+	+	+ +	+	+ +
Checkley et al., 2014	−	+	+ +	+	+ +	+ +	+ +	+	+	+	+	+ +
Chung et al., 2018	−	+	+ +	+	+ +	+ +	+ +	+ +	−	+ +	+	+ +
Griffiths et al., 2016	−	+ +	+ / + + *	+ / + + *	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+ +
Kim and Kim, 2020	−	+	+	+	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+
Neuraz et al., 2015	+ +	+	+	+ +	+ +	+ +	+	+	+	+	+	+
Peelen et al., 2007	−	+	+ +	+ +	+ +	+ +	+ +	+	+	+ +	+	+ +
Ricciardi et al., 2014	−	+	+ +	+ +	+ +	+ +	+ +	+ +	+	+ +	+	+ +
Robertson and Hassan, 1999	−	+	+ +	+	+ +	+ +	+ +	+	+	−	+	+ +
Smith et al., 2007	−	+	+ +	+ +	+ +	+ +	+ +	+	+	+ +	+	+ +
West et al., 2014	−	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+ +	+ +

^*High risk of bias (weak), + moderate, + + low risk of bias (strong) *Different rating for different aspects of the study (national vs selective sample)

ISSN: 1478-4491