Is this photograph really from the first day after Sweden switched the side of the road they drove on?
This one is actually pretty easy. We
reverse image search, and as always check the auto-suggested
text. In this case the text reads day sweden switched
sides of the road which means we should be very, very
cautious. If this picture is mislabeled this text would
probably bias our results.
If the top results didn't look so good, we might change that search text to something more neutral (for instance, road traffic, etc. But the top result is from Wikipedia and the blurb says "the day on 3 September 1967, in which the traffic in Sweden switched from driving on the left-hand side of the road to the right" which looks like what we need.
So we get to the Wikipedia page and find this warning at the top.
It's particularly worrisome because it's a recent message. A lot of times these warnings on Wikipedia are outdated, and the problems have been fixed -- but this one is only a couple months old.
We could do a few things here. First of all, while this article needs additional sources for verification of details, it is highly unlikely that the basics of the article are wrong -- an editor wouldn't leave up an article about a fake event. But if we're going to read something about this day we want it to be well-sourced.
Let's see if this warning is out-of-date or contested. We'll do that by going to the history tab.
This is higher-level analysis, but one
thing I notice here is that this warning was applied by AnomieBot,
a page-checking "bot" -- that is, an automated page checker.
Bots on Wikipedia are good -- they are
part of the reason why Wikipedia is so resilient to
disinformation. Bots find vandalism, biased language,
unsourced articles, and non-notable subjects. But they also
make mistakes. A bot of this sort, for example, may have just
applied this tag because the ratio of words to citations was
low. Such a ratio might be a matter of citation style, or the
particular topic.
I know this is the account that applied the warning because of
the date, but also becuase of the {{Ref improve}}
comment here, which means "Needs additional references" and
applied the warning.
In this case, from my more Wikipedia literate perspective I think this page will likely be fine for getting a summary of this event, even if not rock-solid on details. And it's certainly the case that the photo is correctly identified. But when seeing a warning -- and especially a recent one -- it's always good to check.