Database selection and data gathering methods in systematic reviews of qualitative research regarding diabetes mellitus - an explorative study

Table 3 Individual and combined recall rates of references in the included databases

Databases	References found (n)	Overall recall^a (%)	Median recall^b (%)	Minimum recall^c (%)	100% recall^d (%)	Number of SRs that searched the database, n (% of the 26 SRs)
GSc	486	97.0	100.0	84.6	73.1	1 (3.9)
SCO	462	92.2	76.8	50.0	38.5	4 (15.4)
EMB	443	88.4	89.3	60.0	23.1	12 (46.2)
ML/PM	436	87.0	93.3	62.5	42.3	26 (100.0)
CIN	386	77.1	80.0	25.0	11.5	20 (76.9)
WoS	386	77.1	76.8	50.0	11.5	8 (30.8)
PSI	195	38.9	40.0	0.0	0.0	12 (46.2)
Combinations of two databases^e
GSc + EMB	497	99.2	100.0	87.5	84.6	1 (3.8)
GSc + SCO	492	98.2	100.0	84.6	88.5	0 (0)
GSc + Wos	491	98.0	100.0	87.5	76.9	0 (0)
ML/PM + CIN	483	96.4	100.0	75.0	69.2	20 (76.9)
CIN + SCO	482	96.2	100.0	77.8	65.4	3 (11.5)
EMB + CIN	481	96.0	100.0	75.0	65.4	9 (34.6)
Combinations of three databases^f
GSc + ML/PM + EMB	499	99.6	100.0	87.5	92.3	1 (3.8)
GSc + EMB + CIN	499	99.6	100.0	92.3	92.3	1 (3.8)
GSc + EMB + SCO	498	99.4	100.0	87.5	88.5	0 (0)
ML/PM + EMB + CIN	495	98.8	100.0	80.0	80.8	9 (34.6)
EMB + CIN + WoS	493	98.4	100.0	83.3	76.9	1 (3.8)
ML/PM + CIN + WoS	492	98.2	100.0	83.3	80.8	6 (23.1)

CIN CINAHL, EMB embase, GSc Google Scholar, ML/PM MEDLINE/PubMed, PSI PsycINFO, SCO Scopus, WoS Web of Science
^aOverall recall: The total number of included references retrieved by the databases divided by the total number of included references
^bMedian recall: The median value of recall per systematic review
^cMinimum recall: The lowest value of recall per systematic review
^d100% recall: The percentage of systematic reviews for which the database or database combination retrieved all included references
^eResults of the combination of two databases are presented for the three combinations that yielded the highest results both with and without Google Scholar. For the results of the remaining database combinations see Appendix 2
^fResults of the combination of three databases are presented for the three combinations that yielded the highest results both with and without Google Scholar. For the results of the remaining database combinations see Appendix 2

ISSN: 1471-2288