**Table 1: Trends in accessibility and quality of health facilities in seven provinces, 1991 to 2000**

||**1991**|**1993**|**1997**|**2000**|
|---|---|---|---|---|
|For the closest health facility:|||||
|Mean travel time (minutes)|10|9.7|9.8|10.7|
|Mean real cost of travel (real yuan)|0.03|0.06|0.07|0.13|
|Mean waiting time (minutes)|17.6|15.2|11.7|8.7|
|Mean real cost of treating a cold|3.8|5.6|6.2|8.8|
|%householdsreportingmedicine usually available|91.1%|93.3%|92.8%|93.6%|

Source. China Health and Nutrition Survey, 1991-2000.

Note. Information was collected on every facility that the household can use, and the means are calculated for the facility that is closest (in distance) to the household. Values are calculated for households with at least one child under 12. F tests show that the differences between mean values for 1991 and 2000 are all statistically significant at the 1% level, except for the “percentage reporting medicine generally available” which is significant at the 10% level.

# **3. The theoretical model**

The theoretical approach adopted in this paper has its origins in Becker’s microeconomic model of household production (Becker 1965; Becker 1981) and the expansion of this model to the demand for health (Grossman 1972). The application of this model to child health status is well-documented (Behrman and Deolalikar 1988; Strauss and Thomas 1995; Currie 2000).

It assumes a one-period unitary model of decision-making whereby a household maximizes a **utility function** that depends on the consumption of commodities including a composite (market-purchased) household consumption good ( _Xjt_ ), the consumption of leisure by all household members ( _Ljt_ ) and child health or nutritional status ( _Hijt_ ), conditional on a set of household taste and preferences shifters ( _Wjt_ ): The household faces three constraints:

**(i) a health production function** representing the technology available to the household to transform available inputs into the health of the child. According to this function, the health or nutritional status of child _i_ in household _j_ in period _t_ is:

where nutritional status depends on _Mijt_ , the endogenous material health inputs (such as immunizations, nutritional intake, healthcare utilization); on _Zijt_ , the exogenous characteristics of the child and the household in which it lives; and on Vijt, the endogenous child health-related time inputs. Child health is also conditional on two vectors of exogenous child-specific ( _Gijt_ ) and household/community-specific ( _Fjt_ ) variables that are time-varying or time-invariant indicators of health technology<sup>1</sup> . As such, they influence the choice of health inputs and/or the efficiency with which existing inputs are combined to produce child health, and in so doing affect the shape of the health production function. Exogenous child-specific factors ( _Gijt_ ) could include age, sex and whether the child is an only-child. An example of an exogenous endowment at the household-level ( _Fjt_ ) is the education of the caregiver (typically the mother) who makes health-related decisions that impact on the child’s health. At the community-level, prevailing cultural norms regarding child health practices, the availability of healthcare facilities, relative food prices and communication or transportation infrastructure are examples of _Fjt_ variables.

4