Family characteristics of included infants born between 2014 and 2018 in the Farafenni Health and Demographics Surveillance System and their association with mortality in each of the three periods considered (neonatal, ≤28 days; postneonatal, 28–365 days and first year, 0–365 days)
| Died in ≤28 days | Died in >28–365 days | Died in 0–365 days | Alive at 365 days | Total | |
| Subjects | 64/7131 (0.90%) | 62/7152 (0.87%) | 126/7365 (1.71%) | 7239/7365 (98.29%) | 7365 |
| Family characteristics | |||||
| Age of mother at birth of infant (years) | Num: p=0.839 Cat: p=0.135* | Num: p=0.977 Cat: p=NA | Num: p=0.872 Cat: p=0.885 | ||
| Median (IQR) | 27 years (27–33) | 26 years(24–30.75) | 26 years (23–33) | 27 years (22–32) | 27 years (22–32) |
| <18 | 6 (9.52%) | 0 (0%) | 6 (4.88%) | 318 (4.59%) | 324 (4.6%) |
| 18–35 | 47 (74.60%) | 52 (86.67%) | 99 (80.49%) | 5703 (82.32%) | 5802 (82.29%) |
| 36+ | 10 (15.87%) | 8 (13.33%) | 18 (14.63%) | 907 (13.09%) | 925 (13.12%) |
| Missing | 1 | 2 | 3 | 311 | 314 |
| Age of father at birth of child (years) | Num: p=0.943 Cat: p=0.954 | Num: p=0.857 Cat: p=0.910 | Num: p=0.955 Cat: p=0.915 | ||
| Median (IQR) | 40 years (33–48) | 40 years (33–49) | 40 years(33–48.5) | 40 years (33–47) | 40 years (33–48) |
| <41 | 27 (52.94%) | 25 (54.35%) | 52 (53.61%) | 2816 (53.17%) | 2868 (53.18%) |
| 41+ | 24 (47.06%) | 21 (45.65%) | 45 (46.39%) | 2480 (46.83%) | 2525 (46.82%) |
| Missing | 13 | 16 | 29 | 1943 | 1972 |
| Age of household head (at start of each episode)† | Num: p=0.480 Cat: p=0.699 | Num: p=0.516 Cat: p=0.446 | Num: p=0.904 Cat: p=0.796 | ||
| Median (IQR) | 52 years (44–63) | 52 years(41.75–63.25) | 52 years (43–63) | 53 years (44–63) | 53 years (44–63) |
| 20–40 | 0.18 (11.93%) | 4.84 (20.15%) | 6.02 (19.92%) | 952.16 (18%) | 958.18 (18.01%) |
| 41+ | 1.33 (88.07%) | 19.19 (79.85%) | 24.2 (80.08%) | 4338.67 (82%) | 4362.87 (81.99%) |
| Missing | 0 | 0.54 | 0.55 | 902.75 | 903.3 |
| Spacing to previous sibling | p<0.001‡ | p=NA | p<0.001‡ | ||
| <18 months | 1 (1.56%) | 0 (0%) | 1 (0.81%) | 101 (1.46%) | 102 (1.45%) |
| 18–36 months | 23 (35.94%) | 24 (40.00%) | 47 (37.9%) | 3191 (46.03%) | 3238 (45.89%) |
| >36 months | 14 (21.88%) | 23 (38.33%) | 37 (29.84%) | 2013 (29.04%) | 2050 (29.05%) |
| Died before index birth | 8 (12.50%) | 2 (3.33%) | 10 (8.06%) | 148 (2.14%) | 158 (2.24%) |
| No elder sibling | 18 (28.13%) | 11 (18.33%) | 29 (23.39%) | 1479 (21.34%) | 1508 (21.37%) |
| Missing | 0 | 2 | 2 | 307 | 309 |
| Birth order | p=0.017 | p=0.890 | p=0.136* | ||
| First | 18 (28.13%) | 11 (18.33%) | 29 (23.39%) | 1479 (21.31%) | 1508 (21.34%) |
| Second, third or fourth | 18 (28.13%) | 28 (46.67%) | 46 (37.1%) | 3205 (46.17%) | 3251 (46.02%) |
| Fifth or higher | 28 (43.75%) | 21 (35.00%) | 49 (39.52%) | 2257 (32.52%) | 2306 (32.64%) |
| Missing | 0 | 2 | 2 | 298 | 300 |
| Singleton/multiple pregnancy | p=0.059* | p=0.020 | p=0.003 | ||
| Singleton pregnancy | 56 (87.50%) | 52 (86.67%) | 108 (87.1%) | 6548 (94.34%) | 6656 (94.21%) |
| Multiple pregnancy | 8 (12.50%) | 8 (13.33%) | 16 (12.9%) | 393 (5.66%) | 409 (5.79%) |
| Missing | 0 | 2 | 2 | 298 | 300 |
| Education level of mother | p=0.224 | p=0.724 | p=0.220 | ||
| None, other, vocation | 5 (9.09%) | 8 (15.69%) | 13 (12.26%) | 883 (15.52%) | 896 (15.46%) |
| Religious (Quranic education) | 32 (58.18%) | 25 (49.02%) | 57 (53.77%) | 2463 (43.3%) | 2520 (43.49%) |
| Lower basic/primary | 2 (3.64%) | 1 (1.96%) | 3 (2.83%) | 311 (5.47%) | 314 (5.42%) |
| Upper basic, junior secondary, senior secondary, madaras, college or university | 16 (29.09%) | 17 (33.33%) | 33 (31.13%) | 2031 (35.71%) | 2064 (35.62%) |
| Missing | 9 | 11 | 20 | 1551 | 1571 |
| Education level of father | p=0.007§ | p=0.150 | p=0.005§ | ||
| None, other, vocation | 2 (4.00%) | 2 (5.26%) | 4 (4.55%) | 409 (8.81%) | 413 (8.73%) |
| Religious (Quranic education) | 34 (68.00%) | 30 (78.95%) | 64 (72.73%) | 2715 (58.5%) | 2779 (58.77%) |
| Lower basic/primary | 6 (12.00%) | 1 (2.63%) | 7 (7.95%) | 174 (3.75%) | 181 (3.83%) |
| Upper basic, junior secondary, senior secondary, madaras, college or university | 8 (16.00%) | 5 (13.16%) | 13 (14.77%) | 1343 (28.94%) | 1356 (28.67%) |
| Missing | 14 | 24 | 38 | 2598 | 2636 |
| Education level of household head† | p=0.144 § | p=0.865 | p=0.217 | ||
| None, other, vocation | 0.1 (6.53%) | 0.79 (3.73%) | 1.12 (4.16%) | 396.2 (8.04%) | 397.33 (8.01%) |
| Religious (Quranic education) | 1.21 (80.22%) | 16.36 (76.76%) | 20.64 (76.54%) | 3341.16 (67.77%) | 3361.8 (67.81%) |
| Lower basic/primary | 0.02 (1.45%) | 0.24 (1.1%) | 0.33 (1.24%) | 114.33 (2.32%) | 114.67 (2.31%) |
| Upper basic, junior secondary, senior secondary, madaras, college or university | 0.18 (11.8%) | 3.92 (18.41%) | 4.87 (18.06%) | 1078.76 (21.88%) | 1083.63 (21.86%) |
| Missing | 0.01 | 3.26 | 3.81 | 1263.12 | 1266.93 |
| Sex of household head† | p=0.956 | p=0.252 | p=0.390 | ||
| Male | 1.32 (86.98%) | 22.94 (95.47%) | 28.7 (94.98%) | 4771.02 (90.15%) | 4799.72 (90.17%) |
| Female | 0.2 (13.02%) | 1.09 (4.53%) | 1.52 (5.02%) | 521.45 (9.85%) | 522.97 (9.83%) |
| Missing | 0 | 0.54 | 0.55 | 901.11 | 901.66 |
Row percentages do not add up to 100% because the sample size is slightly different for each group. P values are for the univariable analysis (Cox regression) of each risk factor on mortality in each time period (values <0.05 are bolded). Bolded p values indicate statistical significance.
*This variable was included in the multivariable model, as p<0.20.
†Time-varying variable. Categories described in person-years (%).
‡This variable was not included in the multivariable model, despite having a significant association with the outcome at the univariable level, because it was highly correlated with ‘birth order’. It was included in the sensitivity analyses, though.
§This variable was not included in the multivariable model, despite having a significant association with the outcome at the univariable level, because of the high number of missing values.
cat, categorical variable; num, numerical variable.