Table 1. Characteristics of babies in 112 units recorded in NNRD with BSI caused by clearly pathogenic organisms during NNU admission from linkage to national infection surveillance data and/or clinical records of BSI.
| i) Babies with a clinical record of BSI in NNRD + a link to surveillance data (likely true matches) |
ii) Babies with a clinical record of BSI in NNRD + no link to surveillance data (potential missed matches) |
iii) Babies without a clinical record of BSI in NNRD + a link to surveillance data (BSI not recorded in NNRD) |
iv) Any record of BSI a: All babies with a clinical record of BSI in NNRD +/- a link to surveillance data |
|
|---|---|---|---|---|
| Primary measure with (iii) | Primary measure with (i) | (sum of i) + ii) + iii)) | ||
| Total (% of babies with any record of BSI) | 1,046 | 688 | 1,995 | 3,729 |
| Age at BSI b | ||||
| 2–6 days | 138 (13%) | 116 (18%) | 306 (15%) | 560 (15%) |
| 7–13 days | 259 (25%) | 163 (25%) | 478 (24%) | 900 (24%) |
| 14–20 days | 183 (18%) | 108 (17%) | 275 (14%) | 566 (15%) |
| 21–27 days | 121 (12%) | 54 (8%) | 20 (10%) | 381 (10%) |
| 28–365 days | 345 (33%) | 204 (32%) | 730 (37%) | 1,279 (35%) |
| p-value from chi-squared test | 0.034 | 0.016 | ||
| Gestation b | ||||
| <26 | 390 (27%) | 212 (31%) | 633 (32%) | 1,235 (33%) |
| 26 to <28 | 238 (23%) | 152 (22%) | 406 (20%) | 796 (21%) |
| 28 to <32 | 270 (26%) | 174 (25%) | 476 (24%) | 920 (25%) |
| 32 to <37 | 102 (10%) | 73 (11%) | 274 (14%) | 449 (12%) |
| 37+ | 46 (4%) | 72 (11%) | 206 (10%) | 324 (9%) |
| p-value from chi-squared test | <0.001 | <0.001 | ||
| Year of sample | ||||
| 2010 | 44 (4%) | 52 (8%) | 295 (15%) | 390 (11%) |
| 2011 | 119 (11%) | 109 (17%) | 313 (16%) | 541 (15%) |
| 2012 | 166 (16%) | 132 (20%) | 250 (13%) | 548 (15%) |
| 2013 | 194 (19%) | 113 (18%) | 182 (9%) | 489 (13%) |
| 2014 | 201 (19%) | 123 (19%) | 200 (10%) | 524 (14%) |
| 2015 | 140 (13%) | 69 (11%) | 269 (13%) | 478 (13%) |
| 2016 | 116 (11%) | 35 (5%) | 311 (16%) | 462 (13%) |
| 2017 (up to June) | 66 (6%) | 12 (2%) | 176 (9%) | 254 (7%) |
| p-value from chi-squared test | <0.001 | <0.001 | ||
| Organism groupc | ||||
| E. coli | 172 (17%) | 113 (17%) | 395 (20%) | 680 (18%) |
| Enterobacter | 94 (9%) | 46 (7%) | 167 (8%) | 307 (8%) |
| Klebsiella | 113 (11%) | 58 (9%) | 185 (9%) | 356 (10%) |
| Other gram negative bacteria | 89 (9%) | 49 (7%) | 182 (9%) | 320 (9%) |
| Group B Streptococcus | 79 (8%) | 68 (10%) | 154 (8%) | 301 (8%) |
| S. aureus | 243 (23%) | 205 (30%) | 451 (23%) | 899 (24%) |
| Enterococcus | 176 (17%) | 87 (13%) | 327 (17%) | 590 (16%) |
| Other gram positive bacteria | 10 (1%) | 10 (1%) | 31 (2%) | 51 (1%) |
| Fungi | 61 (6%) | 44 (6%) | 80 (4%) | 185 (5%) |
| p-value from chi-squared test | 0.006 | 0.128 |
a BSI caused by clearly pathogenic organisms with a sample date between two days after admission and two days following discharge
b Babies with missing data for age/gestation excluded from percentages
c For babies with more than one BSI, organism is from the first BSI