Thanks. I did a quick reading through the documents but didn’t see much information about their testing samples and how they are related to RIVM data, so it is difficult to put things in a context.
A quick and dirty estimation based on the numbers of their last report (17% of the population with reported flu symptoms and 8% of flu symptoms tested for coronavirus) gives 1,36% of the population with coronavirus. Which would definitely lower than the actual, since it doesn’t take into account asymptomatic cases and some of those with the symptoms that do not get reported.
And, an article citing the numbers of tests done a week before says that 57 samples were tested and only 2 gave coronavirus (https://www.nrc.nl/nieuws/2020/03/14/corona-stresstest-premier-slaagt-volk-zakt-a3993747). I do not expect that the numbers for this week are much bigger. If this is the data that the government is relying upon to make decisions next to testing reported by RIVM than I am even more worried than before.
It was also amazing to see how the tone of the articles changes from “don’t panic, we know what we are doing” (above) to “nobody could see it coming” (https://www.nrc.nl/nieuws/2020/03/20/dreigingen-werden-hier-nooit-echt-nu-wel-a3994476). And yes, the author is very opinionated, but this is also how the tone of the messages from the government has changed in practically a week time. I just got an emergency alert via sms while a week ago they were still discussing if schools should be closed.
So, I do not share your optimism about well-grounded decision-making in the Netherlands. I do not see the data and the methods used to interpret it to be so sure.