living in the Mekong delta, but arnong the poor living in these areas significantly _reduces_ survival prospects. This does not change over time, and none of the other regional coefficients are significant. The child's gender and age have no significant effect on survival prospects-this is the same for 1993 and 1998, and for the poor and nonpoor. Consumption of itself has no significant effect, but the evidence suggests its impact may have risen over time-albeit not significantly. The effect of consumption appears through the interaction terms, several of which _are_ significant. Mother's education significantly improves survival prospects, and there is no significant difference across consumption groups or over the two time periods. This is consistent with several other studies of child survival (Hobcraft, McDonald, and Rutstein 1985; Merrick 1985; Lee, Rosenzweig, and Pitt 1997; Guilkey and Riphahn 1998), though some studies have found little evidence of a link (Benefo and Schultz 1996; Lavy and others 1996). Having access to satisfactory drinking water also significantly improves a child's survival prospects. Again, this is consistent with several previous studies (Merrick 1985; Ridder and Tunali 1999) but the effect is not found everywhere (Benefo and Schultz 1996; Lee and others 1997). At the 15 percent level, the effect of drinking water is lower among the poor (indeed it is negative)-this difference is consistent with earlier studies of child mortality (Esrey and Habicht 1988) and with recent work on child morbidity (Jalan and Ravallion 2001). Satisfactory sanitation, by contrast, has no significant effect on survival prospects, and the evidence suggests that, if anything, this effect is larger (though not significantly so) among the poor. The lack of significance of the sanitation coefficient is consistent with some recent studies ( Lee, Rosenzweig, and Pitt 1997), but not others (Ridder and Tunali 1999), and the tendency toward a larger effect among the poor is consistent with Esrey and Habicht (1988), who found a larger effect of sanitation among the better-educated.

Turning to the effects of the health service variables, vaccination coverage in the child's village is associated with significantly better survival prospects-a result that is consistent with previous studies using different methods (Koenig, Bishai, and Ali Khan 1990). There is no significant difference over time or across consumption groups, which goes against some recent work in Bangladesh that suggests that the poor benefit more from vaccination (Koenig and others 2001). The only significant coefficient on the antenatal visit coverage variable is that on the interaction with the "poor" dummy, which is negative. Taken at face value, this implies a negative impact of such visits on child survival among the poor and no significant effect on the nonpoor. By contrast, among the poor, the coverage of medically attended deliveries has a positive and significant effect on survival prospects of poor children, but not on those of nonpoor children. This is consistent with recent evidence from Brazil (Furquim De Almeida and others 2000), suggesting that home births carry a higher neonatal mortality risk, but only among poorly educated mothers. All else constant, coverage of facility deliveries has no significant 18