In the previously published reports and the results presented here, the tests were run by laboratory experts in highly regulated laboratory settings, conditions that are not likely to be found in low-resource settings. In this study, the qualitative tests were performed at low ambient temperatures (mean temperature of 20.2°C; range = 18°C to 23°C). Given the temperature dependence of enzyme activity and the probable higher operational temperatures in malaria-endemic settings, it is likely that the performance of these tests will decline further at lower cutoff values in those settings.