I assume you mean there might be a self-selection issue with people who are voluntarily ("privately") insured, as compared to those who have the normal state-mandated ("gesetzlich") insurance?
This data is from AOK which is one of the state-mandated insurers. It insures around 2M people, and my gut feeling is that they are not terribly unrepresentative of the workforce as a whole.
But of course the point is, everyone with a tiny bit of true data could tell much more precise stories, and the journalists (as usual) didn't care or didn't think it would fly with readers.
In Germany there’s private insurance which can only be chosen by people of higher salary and good health because the rate depends on their condition when they sign up. So this data would be biased towards sick people, people doing jobs that are more likely to make you sick, and people who are financially less well off.
For clarification, “default” above doesn’t mean “In Berlin you get insured with TK by default”, and rather “Most people in Berlin will recommend choosing TK over a different state-mandated insurer”. TK was also very popular when I was back in university in Frankfurt. It might just still be the one with reasonable prices!
This data is from AOK which is one of the state-mandated insurers. It insures around 2M people, and my gut feeling is that they are not terribly unrepresentative of the workforce as a whole.
But of course the point is, everyone with a tiny bit of true data could tell much more precise stories, and the journalists (as usual) didn't care or didn't think it would fly with readers.