Table 4 Paired t-test
| Â | 2013 | 2015 | Mean diff | t |
|---|---|---|---|---|
OOP | ||||
 Total | 201.55 ± 242.82 | 206.12 ± 266.52 | 4.57 | 0.55 |
 Treatment | 234.09 ± 259.05 | 232.84 ± 280.25 | −1.25 | − 0.12 |
 Control | 100.04 ± 141.47 | 122.74 ± 196.36 | 22.70 | 2.03* |
Household income | ||||
 Total | 3071.16 ± 3142.24 | 3052.22 ± 2864.47 | − 18.94 | − 0.38 |
 Treatment | 3136.96 ± 2789.89 | 3185.58 ± 3028.96 | 48.62 | 0.83 |
 Control | 2865.88 ± 4047.00 | 2636.15 ± 2228.93 | − 229.73 | −1.29 |