Table 3. The criteria applied to determine the four assay advancement stages.

Advancement stage	Criteria
Stage 1: assay development	▪ The discovery and investigation (e.g., epitopes, protein structures, and glycans) of new detection agents  ▪ The assessment of the detection agent’s performance using a particular technology principle  ▪ The determination of the optimal target analyte (e.g., isotype) and its dynamics over time  ▪ The evaluation of cross-reactivity
Stage 2: cut-off establishment	▪ The establishment of a diagnostic cut-off to distinguish between positive and negative samples
Stage 3: research use	▪ The use of assays in endemic settings to investigate a range of specific epidemiological questions, such as determining the prevalence in a population, examining how this prevalence varies across different demographic factors (e.g., age and sex), identifying risk factors for infection, investigating the infection dynamics and transmission patterns, assessing the effectiveness of different control strategies, identifying how infections interact with other health outcomes (e.g., malnutrition and other infections)  ▪ Investigation of the potential of assays to be used in epidemiological studies
Stage 4: routine implementation to guide STH prevention and control programs	▪ The use by the intended user in target populations to guide prevention and control programs (e.g., used by veterinarians in pig herds to assess the impact of deworming, used by program managers to guide MDA programs)