Table 1.
Reporting characteristics of data sources of the included studies
| Reporting item | Total | Journal type | ||
|---|---|---|---|---|
| (n = 222) | Top 5 general medicine (n = 19) |
Non-top-5 general medicine (n = 203) |
P value | |
| Linkage between data sources, n(%) | 53(23.9) | 12(63.1) | 41(20.2) | < 0.001 |
| Reporting the methods of linkage, n (%) | 22(41.5) | 4(33.3) | 18(43.9) | 0.740 |
| Type of data source reported, n(%) | 202(91.0) | 18(94.7) | 184(90.6) | > 0.999 |
| Name of database reported, n(%) | 195(87.8) | 19(100.0) | 176(86.7) | 0.139 |
| Full name | 66(29.7) | 6(31.6) | 60(29.6) | > 0.999 |
| Abbreviation name | 4(1.8) | 0(0.0) | 4(2.0) | |
| Both full and abbreviation name | 125(56.3) | 13(68.4) | 111(54.7) | |
| Whether the name of database include the type of data source, n (%) | 0.282 | |||
| Yes | 89(40.1) | 6(31.6) | 83(47.2) | |
| Partly* | 20(9.0) | 4(21.1) | 16(9.1) | |
| Unclear† | 25(11.3) | 3(15.8) | 22(12.5) | |
| Not include | 61(27.5) | 6(31.6) | 55(31.3) | |
| Coverage of data source, n(%) | 211(95.0) | 18(94.7) | 193(95.1) | > 0.999 |
| Categories of specific country, n(%) | 206(92.8) | 19(100.0) | 187(92.1) | 0.372 |
| Data resource‡, n(%) | 130(58.6) | 15(78.9) | 115(56.7) | 0.100 |
| Data collected§, n(%) | 151(68.0) | 17(89.5) | 134(66.0) | 0.066 |
| Timeframe of database, n(%) | 81(36.5) | 6(31.6) | 75(36.9) | 0.829 |
| Timeframe of database, median (years) | 22(12, 23) | 30(30, 30) | 22(12, 23) | 0.005 |
| Population coverage, n(%) | 137(61.7) | 13(68.4) | 124(61.1) | 0.702 |
* Study involved multiple databases, but only a part of database contained information related to the type of data source
† The name of the data source containing wording which did not clarify the type of data source, such as “clinical practice”, “health”, and “health information”
‡ Data resource included inpatients records, outpatients records, prescription records, etc.
§ Data collected such as demographics, diagnosis, laboratory and microbiology tests, prescription, operation, etc.