Table 3. Results from between-study meta-regression.
| Fecal indicator bacteria (>1 CFU/100mL) | Total coliforms (>1 CFU/100mL) | |||||
|---|---|---|---|---|---|---|
| Variables | Obs | OR (95% CI) | p-value | Obs | OR (95% CI) | p-value |
| PW type | ||||||
| Small bottles vs. all other PW types | 157 | 0.32 (0.17–0.58) | <0.001* | 170 | 0.10 (0.05–0.22) | <0.001* |
| Small bottles vs. all sachets | 137 | 0.21 (0.10–0.42) | <0.001* | 147 | 0.04 (0.02–0.09) | <0.001* |
| Small bottles vs. machine- filled sachet | 129 | 0.31 (0.16–0.62) | 0.001* | 139 | 0.08 (0.03–0.17) | <0.001* |
| Machine-filled sachet vs. hand-filled sachet | 45 | 0.10 (0.02–0.53) | 0.008* | 44 | 0.04 (0.01–0.26) | 0.001* |
| Study location | ||||||
| LICs vs. UM/HICs | 157 | 4.6 (2.6–8.1) | <0.001* | 170 | 13.6 (6.9–26.7) | <0.001* |
| Africa vs. all other regions | 157 | 3.0 (1.6–5.5) | 0.001* | 170 | 10.7 (5.1–22.6) | <0.001* |
| Asia vs. all other regions | 157 | 1.7 (0.78–3.5) | 0.192 | 170 | 0.94 (0.38–2.3) | 0.889 |
| South America vs. all other regions | 157 | 0.71 (0.35–1.5) | 0.350 | 170 | 0.40 (0.16–0.97) | 0.044* |
| Developed vs. all other regions | 157 | 0.12 (0.05–0.27) | <0.001* | 170 | 0.08 (0.03–0.22) | <0.001* |
| Study characteristics | ||||||
| Random vs. nonrandom | 157 | 1.1 (0.59–2.2) | 0.700 | 170 | 2.3 (1.0–5.2) | 0.041* |
| Representative vs. non-representative | 157 | 0.79 (0.36–1.7) | 0.551 | 170 | 1.3 (0.47–3.5) | 0.629 |
| Longitudinal vs. cross-sectional | 153 | 0.81 (0.32–2.0) | 0.646 | 164 | 1.4 (0.38–5.2) | 0.616 |
| High quality vs. low-quality | 157 | 0.99 (0.44–2.3) | 0.988 | 170 | 2.1 (0.70–6.6) | 0.178 |
| E. coli vs. TTC | 157 | 0.82 (0.44–1.5) | 0.536 |
*significance at 95%