Table 5.

Influencing factors for data quality.

Strategy and influencing factors		Distribution of influencing factor in studies (N=33), n (%)
Strategy: process; influencing factor category: context
	Research-only controlled environment	7 (21.2)
	Transition and validation environment	8 (24.2)
	Restricted routine environment	18 (54.6)
Strategy: techniques/analysis; influencing factor category: study design
	Longitudinal	27 (81.8)
	Cross-sectional	3 (9.1)
	Combined	2 (6.1)
	No information provided/design adopted unclear	1 (3.0)
Strategy: tools; influencing factor category: data source
	Own research repositories	24 (72.7)
	Preexisting data models	4 (12.1)
	Public databases	2 (6.1)
	Other sources	3 (9.1)
Strategy: tools; influencing factor category: study limitations
	Methodological	21 (63.6)
	Technical	15 (45.5)
	Social	6 (18.2)
	Organizational	2 (6.1)
	Legal	1 (3.0)
Strategy: tools; influencing factor category: study design
	Longitudinal	27 (81.8)
	Cross-sectional	3 (9.1)
	Combined	2 (6.1)
	No information provided/design adopted unclear	1 (3.0)