Efficacy and safety of Z-substances in the management of insomnia in older adults: a systematic review for the development of recommendations to reduce potentially inappropriate prescribing

Table 2 Risk of bias assessment of randomized controlled trials

Study	Randomization process	Deviations from intended interventions	Missing outcome data	Measurement of the outcome	Selection of reported results	Overall risk
Ancoli-Israel 2010	Unknown risk	Some concerns	Low risk	Low risk	Low risk	High risk
Ancoli-Israel 1999	Unknown risk	High risk	Low risk	Some concerns	Unknown risk	High risk
Dehlin 1995	Unknown risk	High risk	Low risk	Unknown risk	Unknown risk	High risk
Elie 1990	Unknown risk	High risk	Some concerns	Unknown risk	Unknown risk	High risk
Klimm 1987	Unknown risk	Unknown risk	Low risk	Unknown risk	Unknown risk	High risk
Leppik 1997	Unknown risk	High risk	Low risk	Unknown risk	Unknown risk	High risk
Roger 1993	Unknow risk	High risk	Some concerns	Unknow risk	Unknown risk	High risk
Scharf 2005	Unknown risk	High risk	Low risk	Unknown risk	Low risk	High risk

ISSN: 1471-2318