A generalised way of thinking about sanitation quality of service and quality of life

In a previous post, I wrote about how I see measures of quality of service (QoS) and quality of life (QoL) capturing different things which are both important. In this post, I expand on that, proposing a generalised way of thinking about this at different stages of the service chain. First, though, a few words on user satisfaction and objectivity.

Distinction between QoL and user satisfaction

In the last post I skipped over user satisfaction, but I think it’s important to describe the subtle difference between user satisfaction and QoL. In marketing, theoretical groundings of customer satisfaction are focused on the product. For example, one influential marketing theory focuses on expectations about a product’s “ideal”, “expected minimum”, “tolerable”, and “desirable” performance. For sure, this involves psychological processes, but it is focused on the product not the person.

To illustrate this, consider these two questions asking about a similar concept:

1. How satisfied are you with the cleanliness of the bathroom?
2. Can you feel clean while carrying out your sanitation practices?

It’s likely that responses for these two questions would be highly correlated. However, there is an important conceptual difference, and it’s rooted in whether the question asks about an attribute of the service/infrastructure or about an attribute of the person/QoL.

Subjectivity and objectivity

The distinction between subjectivity and objectivity in measurement is clearly important. Most measurements are unlikely to be objective in the philosophical sense. However,  achieving objectivity in the scientific sense is often an implicit goal in QoS measures. To be classed as objective, the value for a QoS variable should theoretically be the same regardless of the rater. The mean queuing time at a public toilet should be more or less the same for all (by gender and time of day, at least).

Subjective measures, meanwhile, may differ a priori between people using the same service (I gave an example for SanQoL for users of the same toilet in the last post). Inter-rater reliability, i.e. whether the person asking the questions makes a difference, is nonetheless a concern in some measures. Of course, many sanitation QoS measures that are theoretically objective require some element of subjective judgement by the rater. For example, two different enumerators amy have different thresholds for answering yes/no to “are faeces present on the slab?”. So subjectivity is really a continuum not a binary attribute.

A matrix incorporating subjectivity and objectivity

I applied these ideas in a 2×2 matrix on QoS and QoL with respect to toilets – see below. Most should be obvious from this post and the previous, except for quadrant C on proxies. On the one hand, it may not be possible for anyone other than the individual themselves to scale their QoL adequately. However, out of necessity, health economists have developed proxy measures for people who are too young or incapacitated to rate health-related QoL themselves. It is not too hard to imagine the same for SanQoL, though hardly a priority right now.

This touches on the issue of “who is the rater?”. At the containment stage of the sanitation service chain, one can imagine many types of rater. For QoL it would ideally be the user themselves (though cf. proxy discussion above). For QoS it could be the user, a non-specialist observer (e.g. typical enumerator) or a sanitation specialist. The main difference between the specialist and non-specialist is that only the former would be qualified to inspect or evaluate sub-surface infrastructure. One example is the verification that what the user calls a “septic tank” really is a septic tank not a holding tank or soak pit (see bottom of p.36 in this Indonesian study re: discussion of “cubluk”).

Generalising to the sanitation service chain

Here’s a more generalised framework for QoS and QoL along the sanitation chain. Taking QoL first, the measure of SanQoL I’m working on is assessing QoL attributes of the user at the containment stage. At the emptying & transport stage, however, it would be more appropriate to assess QoL of workers. Same for the treatment & reuse stages. Some people are working on measuring sanitation workers’ conditions, for example, which would fall into that category.

QoL could be “objectively” proxied by a caregiver or observer, though with many caveats on the reliability of that data – better to ask the person themselves unless impossible to do so. As with the earlier 2×2 matrix, I would put user satisfaction in the box of subjective QoS metrics. This can be measured for containment services or emptying services.

The basket of “objective” QoS measures, meanwhile, is very large. It could range from infrastructure observations by an enumerator, through to measurements from technical instruments (e.g. for treatment efficiency) or financial and economic performance metrics.

Conclusion

Certainly there is plenty of room for better measurement of outcomes affected by sanitation interventions. In this post, I’ve explored the concepts of subjectivity and objectivity with respect to measuring QoS and QoL for sanitation services. Lots of people have developed measures in this space and one thing I want to do is map this out across the above generalised matrix.