Table 2 Factors associated with birth before arrival at a facility based on household survey in rural Tanzania*
| Â | No matching unadjusted odds ratio (CI) | No matching adjusted odds ratio (CI) | Matchingaunadjusted odds ratio (CI) | Matchingaadjusted odds ratio (CI) | Matchingbunadjusted odds ratio (CI) | Matchingbadjusted odds ratio (CI) |
|---|---|---|---|---|---|---|
Column 1 | Column 2 | Column 3 | Column 4 | Column 5 | Column 6 | |
Age | p = 0.228 | p = 0.931 | p = 0.307 | NA | p = 0.217 | NA |
 Under 16 years | 1 (ref) | 1 (ref) | 1 (ref) |  | 1 (ref) |  |
 16 to 19 years | 1.58 (0.67, 3.71) | 1.07 (0.31, 3.70) | 1.77 (0.76, 4.10) |  | 1.82 (0.80, 4.17) |  |
 More than 19 years | 2.15 (0.89, 5.19) | 1.28 (0.32, 5.22) | 1.96 (0.82, 4.72) |  | 2.19 (0.90, 5.33) |  |
Age at first pregnancy | p = 0.008 | p = 0.074 | p = 0.040 | p = 0.063 | NA | NA |
 Under 16 years | 1 (ref) | 1 (ref) | 1 (ref) | 1 (ref) |  |  |
 16 to 19 years | 0.59 (0.27, 1.26) | 0.79 (0.33, 1.86) | 0.65 (0.30, 1.38) | 0.68 (0.31, 1.46) |  |  |
 More than 19 years | 0.29 (0.13, 0.65) | 0.48 (0.18, 1.27) | 0.35 (0.16, 0.80) | 0.38 (0.16, 0.87) |  |  |
Parity | p = 0.009 | p = 0.108 | p = 0.019 | p = 0.023 | p = 0.027 | p = 0.024 |
 1 | 1 (ref) | 1 (ref) | 1 (ref) | 1 (ref) | 1 (ref) | 1 |
 2–3 | 3.93 (1.36, 11.36) | 4.79 (0.94, 24.5) | 4.01 (1.41, 11.4) | 3.88 (1.33, 11.3) | 3.98 (1.39, 11.4) | 4.05 (1.37, 11.9) |
 4+ | 5.14 (1.82, 14.56) | 4.65 (0.74, 29.1) | 4.22 (1.52, 11.8) | 4.47 (1.53, 13.1) | 3.90 (1.40, 10.8) | 4.30 (1.49, 12.4) |
Woman's education | p = 0.108 | p = 0.896 | p = 0.735 | NA | p = 0.661 | NA |
 None | 1 (ref) | 1 (ref) | 1 (ref) |  | 1 (ref) |  |
 Some Primary | 0.57 (0.19, 1.68) | 0.87 (0.24, 3.11) | 0.71 (0.23, 2.18) |  | 0.51 (0.14, 1.84) |  |
 Primary Complete | 0.51 (0.27, 0.96) | 0.91 (0.37, 2.26) | 0.76 (0.40, 1.45) |  | 0.82 (0.42, 1.60) |  |
 Secondary or Higher | 0.16 (0.02, 1.22) | 0.87 (0.10, 7.55) | 0.37 (0.04, 3.07) |  | 0.39 (0.05, 3.19) |  |
Partner's education | p = 0.425 | p = 0.583 | p = 0.773 | NA | p = 0.794 | NA |
 None/Some Primary | 1 (ref) | 1 (ref) | 1 (ref) |  | 1 (ref) |  |
 Primary Complete | 1.08 (0.31, 3.7) | 2.59 (0.54, 12.4) | 1.43 (0.40, 5.05) |  | 1.53 (0.44, 5.41) |  |
 Secondary or Higher | 0.21 (0.02, 2.13) | 1.25 (0.11, 14.4) | 0.56 (0.05, 5.84) |  | 0.69 (0.06, 7.42) |  |
 None Reported | 1.18 (0.30, 4.72) | 4.01 (0.72, 22.5) | 1.48 (0.37, 5.96) |  | 1.60 (0.39, 6.50) |  |
Asset index quintile | p < 0.001 | p < 0.001 | NA | NA | NA | NA |
 Lowest | 1 (ref) | 1 (ref) |  |  |  |  |
 Second | 1.43 (0.80, 2.57) | 1.08 (0.48, 2.47) |  |  |  |  |
 Middle | 0.61 (0.26, 1.43) | 0.80 (0.31, 2.07) |  |  |  |  |
 Fourth | 0.31 (0.13, 0.74) | 0.36 (0.15, 0.91) |  |  |  |  |
 Highest | 0.12 (0.03, 0.38) | 0.15 (0.04, 0.58) |  |  |  |  |
ANC visits | p = 0.009 | p = 0.006 | p = 0.010 | p = 0.006 | p = 0.051 | p = 0.015 |
 2 or fewer | 1 (ref) | 1 (ref) | 1 (ref) | 1 (ref) | 1 (ref) | 1 |
 3 visits | 0.37 (0.17, 0.82) | 0.34 (0.14, 0.81) | 0.33 (0.14, 0.80) | 0.32 (0.13, 0.27) | 0.36 (0.14, 0.89) | 0.32 (0.13, 0.78) |
 4 or more | 0.38 (0.20, 0.72) | 0.34 (0.16, 0.71) | 0.35 (0.17, 0.71) | 0.33 (0.17, 0.66) | 0.40 (0.18, 0.88) | 0.33 (0.15, 0.72) |
Relationship to head of household | p = 0.506 | p = 0.866 | p = 0.646 | NA | p = 0.579 | NA |
 Self | 1 (ref) | 1 (ref) | 1 (ref) |  | 1 (ref) |  |
 Wife | 0.76 (0.33, 1.77) | 1.07 (0.38, 3.03) | 0.84 (0.36, 1.93) |  | 0.80 (0.34, 1.87) |  |
 Other | 0.55 (0.20, 1.51) | 0.76 (0.26, 2.20) | 0.63 (0.23, 1.71) |  | 0.59 (0.21, 1.62) |  |