Careful reporting of survey findings is important.

Focusing disproportionately on the observation that households with foreign domestic workers use 20 per cent more water than those without (Homes with maids use more water: Survey, March 10) on a daily, per-capita basis - and attributing the higher water consumption to the hypothesis that "washing and cooking activities are done more often in homes with maids" results in two problems.

First, the conflation of correlation and causation, especially when other factors potentially related to consumption, besides the number of individuals in a household, have not been adequately considered; and second, the leap to a causal explanation without convincing empirical evidence.

Careful reporting is important because it guides policy responses. Already we seem to have jumped the gun and placed the onus on domestic workers to make changes, instead of tracing other reasons for the disparity.

Yet, what if water consumption is due to characteristics of the household, many of which may be beyond the control of the worker? They include:

• The size of the home, not just the number of household members.

• The demographics of the members - elderly individuals who need caregiving may have higher consumption rates, as with young children who may not be aware of their use of utilities.

• Activities and behaviours of household members - a higher number of members staying home would mean higher water use - and the expectations employers may have of their domestic workers.

The PUB has to offer more convincing evidence that the maids doing more washing and cooking activities are responsible for higher water consumption.

Is it fair to argue that they are solely to blame, and are the ones who need more information and training?

To what extent do employers put pressure on housework and cleanliness? And how is water consumption divided among household members, not just the domestic worker?

Kwan Jin Yao