Conversion from real Loran has no real mathematical solution but does produce an unreliable solution and can be improved knowing local area offsets. Loran (absolute) accuracy is extremely poor considering what Global Navigation Satellite Systems (GNSS) can provide today. Loran repeatability was reasonably good and the only real way to convert from Loran positions to more recognizable latitude/Longitude is to locate the point using a Loran then recording the position using GNSS/GPS but now there is no Loran then it's time to move on. Why CWOP call the position they use Loran has probably something to do with not understanding the format they are using.
Just to clarify some of the above comments regard typical latitude/Longitude formats commonly used and the wording that should be applied.
dDD MM.mmm would be the most commonly used format in the world today especially with aviation and maritime and which is in line with defacto standards based on NMEA (as used to interface navigation equipment). The reference here is Degrees Minutes & Decimal minutes (seconds should have no mention at all). Typical # decimal minutes is 3 providing an precision of less than 2.8 metres (~ 9 feet) and which can be typically achieved with GNSS/GPS. dDD MM.mmm is also directly usable with navigation charts based on the general value of 1 minute being 1 NM. Just don't confuse Accuracy & Precision, quite different things.
dDD MM SS.sss is more used for land based activities such as high precision surveying. Degrees, Minutes, Seconds and decimal seconds and typically a minimum of 4-5 decimal seconds provides and absolute accuracy of a few millimetres Deci, milli seconds don't come into position at all, those are more to do with time.
dDD.dddddd is simply degrees and decimal degrees and used quite a lot in weather type reports
For computer type applications, data transfer etc then most of the formats follow HP notation dDD.dddddd, dDDmm.mmm & dDDMMSS.sss etc
For non computer display then one must always use the symbols °, ' & " so as to eliminate and confusion with the intended format and if the hemisphere could be confused then also use the N, S, E & W designators or + & -
Mind you Latitude & Longitude is nothing more than a world wide coordinate system that mere mortals can recognize and understand, behind this sits Cartesian ECXYZ which is where all the maths is handled and something that make absolutely no sense to mere mortals.
And yes accuracy/precision has nothing to do with the format, it's more about the application the position is be used for. But this isn't the end of it as any Latitude/Longitude position is rather useless without a datum as the same physical position on earth can have very different Latitude/Longitude coordinates in different datum, same in reverse the same latitude/Longitude coordinates can be a totally different location depending on the datum. Incorrect datum can make a far bigger impact on physical location than using the wrong format, lots of variables and factors with this one.
The good thing about LORAN is it went ..... Poof and the towers all fell down