Valuing an Index of Sanitation Related Quality of Life (SanQoL-5) in urban Mozambique – a Discrete Choice Experiment

Abstract Objectives 1.5 billion people live without basic sanitation. A five-attribute index of sanitation-related quality of life (SanQoL-5) designed for economic evaluation has now been applied in six countries. After rescaling, scores range 0 (no sanitation capability) to 1 (full sanitation capability). To date, SanQoL-5 valuation has been via simple methods such as rank sum, not robust methods such as discrete choice experiment (DCE). We aimed to value the SanQoL-5 index using a DCE in urban Mozambique. Methods We enrolled 601 adults in the cities of Maputo and Dondo, sampling women and men equally alongside quotas for toilet type. The DCE task was a choice between two scenarios representing combinations of SanQoL-5 attribute levels (always, sometimes, never). Each respondent completed 10 tasks and a dominance test. We fitted a mixed logit model and rescaled coefficients to derive the index, with sub-group analysis by gender. Results The highest-valued attribute was disgust (“never feel disgusted while using the toilet”), with a SanQoL-5 index value of 0.25. The other attributes had similar values (ranging 0.18–0.19). People valued “sometimes” levels at around 60% of “never” levels. Mean SanQoL-5 by toilet type followed a gradient with Sustainable Development Goal 6 categories: “open defecation” 0.30, “unimproved” 0.45, “limited” 0.60 and “at least basic” 0.70. Conclusions This is the first DCE-based valuation of any index of sanitation-related quality of life, enabling the SanQoL-5 to be used in economic evaluation. Identifying sanitation service transitions associated with the greatest quality of life gains could inform more efficient resource allocation.