Swan Nilsson Nordström (Sven Svensson) - The discrepancy in Swan's Birth Record

"A common problem arises when birth information (date and/or place) found in a household examination (husförhörslängd - hfl) cannot be verified by a corresponding birth record. How could the hfl entry be incorrect? Those who produced these records often copied household information from the old book to a new one. “If one imagines how this occurred during those earlier times, it’s easy to understand. The priest or clerk, with perhaps less than perfect eyesight, may have sat in the evening in a poorly lit space with the task of transferring all the information from the old book. A book already filled with names stricken out and perhaps not especially well written to begin with. Is it to wonder then that a ‘4’ could have been read as a ‘7’ or ‘3’?” These errors would then be perpetuated as they were copied to subsequent books."

https://familysearch.org/learn/wiki/en/Sweden:_Solving_Common_Probl...

Search Strategy (incorrect date)

1. Follow the individual back in time. Search each of the previous household examinations to confirm that birth information is the same. A basic rule is that information closest to the actual event is the most correct.
2. Follow the individual forward in time to see if the information changes in subsequent renderings.
3. Search the death records. According to regulations beginning in 1686, the age of the deceased was to be included in the death record. Be aware that in the earliest records, these ages may have been somewhat exaggerated as being of a ripe old age was highly valued. In later records, the age at decease is given to the day. When the age is given so precisely the researcher may have greater confidence in its accuracy.
4. If none of the above produces results, the researcher should review all births for the year indicated looking for a child with the appropriate first name and patronymic. This is always done when only a birth year is given.
5. Finally, one may have to search years prior to and after that given in the household examination, in which case a list of several possible candidates may result. In this case, each candidate should be followed forward to adulthood in the household examinations to hopefully find a match.