Table 4.

Definition of quality indicator used by authors

Study identifier (first author, year)	Definition of quality indicator used
den Breejen et al (2013),42 Sewitch et al (2013),43 Uphoff et al (2012),31 Zimmerman et al (2014),32 Cox and Gray (2015),44 Lewis (2009),26 RNAO (2002),25 Silow-Carroll et al (2006),45 Kelley and Hurst (2006),24 OECD website (2006)27 and Carinci et al (201528	Definition not included.
Dreesen et al (2014)29	A quality indicator as a measurable element of practice performance for which there is evidence or consensus that it can be used to assess the quality of care, and hence change the care provided.46
Ouwens et al (2010)30 and Uphoff et al (2012)31	Quality indicators are ‘measurable elements of practice performance for which there is evidence or consensus that they can be used to assess the quality of care’.47
Davies et al (2011)23	An explicit measurable statement of the quality of care given. Relates to a single outcome or process of medical care. Clearly defined and unambiguous.47 48
NHS (2003)22	Items that patients, caregivers and professionals believed were important in achieving the benchmarks of best practice.22
IAPO (2012)21	Can be measures of structure, process and outcome, either as generic measures relevant for all diseases, or disease-specific measures that describe quality of patient care related to a specific diagnosis.49

IAPO, International Alliance of Patients’ Organizations; NHS, National Health Service; OECD, Organization for Economic Cooperation and Development.